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Vail CS, Reiss D, Brakes P, Butterworth A. Potential Welfare Impacts of Chase and Capture of Small Cetaceans during Drive Hunts in Japan. J APPL ANIM WELF SCI 2019; 23:193-208. [PMID: 30806084 DOI: 10.1080/10888705.2019.1574576] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Drive hunts are a method to herd, capture and kill small cetaceans (whales and dolphins) in coastal waters of some countries including Japan and the Faroe Islands. In Japan, these methods are often associated with the acquisition of live dolphins for international marine parks and aquaria. During the hunts, dolphins are herded by a flotilla of fishing vessels and loud underwater noise created by fishermen banging hammers on metal poles. The prolonged and strenuous chase and use of sound barriers to herd, capture, and restrain the dolphins can result in acute stress and injury. The authors review physiological and behavioral data pertaining to chase, encirclement, and live capture of dolphins and draw comparisons between chase and capture data for marine and terrestrial species. This analysis raises substantial welfare concerns associated with the hunts and acquisition of dolphins from such capture operations. The authors assert that this data detailing the negative impacts of chase, herding and handling (capture) of small cetaceans renders these hunts inherently inhumane and should inform policy relating to the collection and management of dolphins in the wild.
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Affiliation(s)
| | - Diana Reiss
- Department of Psychology, Hunter College, City University of New York, New York, NY, USA
| | - Philippa Brakes
- Centre for Ecology and Conservation, University of Exeter, Tremough, Cornwall, UK.,Whale and Dolphin Conservation (WDC), Wiltshire, UK
| | - Andrew Butterworth
- Clinical Veterinary School, University of Bristol Veterinary School, Langford, UK
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52
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Fagot J, Boë LJ, Berthomier F, Claidière N, Malassis R, Meguerditchian A, Rey A, Montant M. The baboon: A model for the study of language evolution. J Hum Evol 2018; 126:39-50. [PMID: 30583843 DOI: 10.1016/j.jhevol.2018.10.006] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2018] [Revised: 10/06/2018] [Accepted: 10/15/2018] [Indexed: 12/13/2022]
Abstract
Comparative research on the origins of human language often focuses on a limited number of language-related cognitive functions or anatomical structures that are compared across species. The underlying assumption of this approach is that a single or a limited number of factors may crucially explain how language appeared in the human lineage. Another potentially fruitful approach is to consider human language as the result of a (unique) assemblage of multiple cognitive and anatomical components, some of which are present in other species. This paper is a first step in that direction. It focuses on the baboon, a non-human primate that has been studied extensively for years, including several brain, anatomical, cognitive and cultural dimensions that are involved in human language. This paper presents recent data collected on baboons regarding (1) a selection of domain-general cognitive functions that are core functions for language, (2) vocal production, (3) gestural production and cerebral lateralization, and (4) cumulative culture. In all these domains, it shows that the baboons share with humans many cognitive or brain mechanisms which are central for language. Because of the multidimensionality of the knowledge accumulated on the baboon, that species is an excellent nonhuman primate model for the study of the evolutionary origins of language.
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Affiliation(s)
- Joël Fagot
- Laboratory of Cognitive Psychology, CNRS and Aix-Marseille University, Marseille, France.
| | | | | | - Nicolas Claidière
- Laboratory of Cognitive Psychology, CNRS and Aix-Marseille University, Marseille, France
| | - Raphaelle Malassis
- Laboratory of Cognitive Psychology, CNRS and Aix-Marseille University, Marseille, France
| | - Adrien Meguerditchian
- Laboratory of Cognitive Psychology, CNRS and Aix-Marseille University, Marseille, France
| | - Arnaud Rey
- Laboratory of Cognitive Psychology, CNRS and Aix-Marseille University, Marseille, France
| | - Marie Montant
- Laboratory of Cognitive Psychology, CNRS and Aix-Marseille University, Marseille, France
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53
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Nummela SU, Jutras MJ, Wixted JT, Buffalo EA, Miller CT. Recognition Memory in Marmoset and Macaque Monkeys: A Comparison of Active Vision. J Cogn Neurosci 2018; 31:1318-1328. [PMID: 30513042 DOI: 10.1162/jocn_a_01361] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
The core functional organization of the primate brain is remarkably conserved across the order, but behavioral differences evident between species likely reflect derived modifications in the underlying neural processes. Here, we performed the first study to directly compare visual recognition memory in two primate species-rhesus macaques and marmoset monkeys-on the same visual preferential looking task as a first step toward identifying similarities and differences in this cognitive process across the primate phylogeny. Preferences in looking behavior on the task were broadly similar between the species, with greater looking times for novel images compared with repeated images as well as a similarly strong preference for faces compared with other categories. Unexpectedly, we found large behavioral differences among the two species in looking behavior independent of image familiarity. Marmosets exhibited longer looking times, with greater variability compared with macaques, regardless of image content or familiarity. Perhaps most strikingly, marmosets shifted their gaze across the images more quickly, suggesting a different behavioral strategy when viewing images. Although such differences limit the comparison of recognition memory across these closely related species, they point to interesting differences in the mechanisms underlying active vision that have significant implications for future neurobiological investigations with these two nonhuman primate species. Elucidating whether these patterns are reflective of species or broader phylogenetic differences (e.g., between New World and Old World monkeys) necessitates a broader sample of primate taxa from across the Order.
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54
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Zhou X, Sun D, Guang X, Ma S, Fang X, Mariotti M, Nielsen R, Gladyshev VN, Yang G. Molecular Footprints of Aquatic Adaptation Including Bone Mass Changes in Cetaceans. Genome Biol Evol 2018; 10:967-975. [PMID: 29608729 PMCID: PMC5952927 DOI: 10.1093/gbe/evy062] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/13/2018] [Indexed: 01/04/2023] Open
Abstract
Cetaceans (whales, dolphins, and porpoises) are a group of specialized mammals that evolved from terrestrial ancestors and are fully adapted to aquatic habitats. Taking advantage of the recently sequenced finless porpoise genome, we conducted comparative analyses of the genomes of seven cetaceans and related terrestrial species to provide insight into the molecular bases of adaptation of these aquatic mammals. Changes in gene sequences were identified in main lineages of cetaceans, offering an evolutionary picture of cetacean genomes that reveal new pathways that could be associated with adaptation to aquatic lifestyle. We profiled bone microanatomical structures across 28 mammals, including representatives of cetaceans, pinnipeds, and sirenians. Subsequent phylogenetic comparative analyses revealed genes (including leptin, insulin-like growth factor 1, and collagen type I alpha 2 chain) with the root-to-tip substitution rate significantly correlated with bone compactness, implicating these genes could be involved in bone mass control. Overall, this study described adjustments of the genomes of cetaceans according to lifestyle, phylogeny, and bone mass.
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Affiliation(s)
- Xuming Zhou
- Jiangsu Key Laboratory for Biodiversity and Biotechnology, College of Life Sciences, Nanjing Normal University, China.,Division of Genetics, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts
| | - Di Sun
- Jiangsu Key Laboratory for Biodiversity and Biotechnology, College of Life Sciences, Nanjing Normal University, China
| | - Xuanmin Guang
- BGI-Shenzhen, Shenzhen, China.,The Key Laboratory of Conservation Biology for Endangered Wildlife of the Ministry of Education, College of Life Sciences, Zhejiang University, Hangzhou, China
| | - Siming Ma
- Genome Institute of Singapore, Singapore
| | | | - Marco Mariotti
- Division of Genetics, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts
| | - Rasmus Nielsen
- Department of Integrative Biology, University of California, Berkeley
| | - Vadim N Gladyshev
- Division of Genetics, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts
| | - Guang Yang
- Jiangsu Key Laboratory for Biodiversity and Biotechnology, College of Life Sciences, Nanjing Normal University, China
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55
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Tønnesen P, Gero S, Ladegaard M, Johnson M, Madsen PT. First-year sperm whale calves echolocate and perform long, deep dives. Behav Ecol Sociobiol 2018. [DOI: 10.1007/s00265-018-2570-y] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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56
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Gonçalves A, Biro D. Comparative thanatology, an integrative approach: exploring sensory/cognitive aspects of death recognition in vertebrates and invertebrates. Philos Trans R Soc Lond B Biol Sci 2018; 373:20170263. [PMID: 30012749 PMCID: PMC6053989 DOI: 10.1098/rstb.2017.0263] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/30/2018] [Indexed: 11/12/2022] Open
Abstract
Evolutionary thanatology benefits from broad taxonomic comparisons of non-human animals' responses to death. Furthermore, exploring the sensory and cognitive bases of these responses promises to allow classification of the underlying mechanisms on a spectrum from phylogenetically ancient to more derived traits. We draw on studies of perception and cognition in invertebrate and vertebrate taxa (with a focus on arthropods, corvids, proboscids, cetaceans and primates) to explore the cues that these animals use to detect life and death in others, and discuss proximate and ultimate drivers behind their capacities to do so. Parallels in thanatological behaviour exhibited by the last four taxa suggest similar sensory-cognitive processing rules for dealing with corpses, the evolution of which may have been driven by complex social environments. Uniting these responses is a phenomenon we term 'animacy detection malfunction', whereupon the corpse, having both animate and inanimate attributes, creates states of fear/curiosity manifested as approach/avoidance behaviours in observers. We suggest that integrating diverse lines of evidence (including the 'uncanny valley' effect originating from the field of robotics) provides a promising way to advance the field, and conclude by proposing avenues for future research.This article is part of the theme issue 'Evolutionary thanatology: impacts of the dead on the living in humans and other animals'.
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Affiliation(s)
- André Gonçalves
- Language and Intelligence Section, Primate Research Institute, Kyoto University, Inuyama, Aichi 484-8506, Japan
| | - Dora Biro
- Department of Zoology, University of Oxford, South Parks Road, Oxford OX1 3PS, UK
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57
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Iwata T, Akamatsu T, Thongsukdee S, Cherdsukjai P, Adulyanukosol K, Sato K. Tread-water feeding of Bryde's whales. Curr Biol 2018; 27:R1154-R1155. [PMID: 29112865 DOI: 10.1016/j.cub.2017.09.045] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Many previous studies have shown that rorqual whales (Balaenopteridae), including the blue whale (Balaenoptera musculus), fin whale (B. physalus), sei whale (B. borealis), Bryde's whale (B. edeni), minke whale (B. acutorostrata), and humpback whale (Megaptera novaeangliae), employ a strategy called lunge feeding to capture a large amount of krill and/or fish for nourishment [1]. Lunge feeding entails a high energetic cost due to the drag created by an open mouth at high speeds [1,2]. In the upper Gulf of Thailand, Bryde's whales, which feed on small fish species [3], predominantly anchovies, demonstrated a range of feeding behaviors such as oblique, vertical, and lateral lunging. Moreover, they displayed a novel head-lifting feeding behavior characterized by holding the vertical posture for several seconds with an open mouth at the water surface. This study describes the head-lifting feeding by Bryde's whales, which is distinct from the typical lunge feeding of rorqual whales. Whales showing this behavior were observed on 58 occasions, involving 31 whales and including eight adult-calf pairs. Whales caught their prey using a series of coordinated movements: (i) lifting the head above the water with a closed mouth, (ii) opening the mouth until the lower jaw contacted the sea surface, which created a current of water flowing into the mouth, (iii) holding their position for several seconds, (iv) waiting for the prey to enter the mouth, and (v) closing the mouth and engulfing the prey underwater (Figure 1A-F, Movie S1 in Supplemental Information published with this article online). When a whale kept its upper jaw above the sea surface, many anchovies in the targeted shoal appeared to lose orientation and flowed passively into the mouth of the whale by the current created by the lower mandible breaking the surface of the water. We measured the duration of feeding events when the whales had a wide-open mouth mostly above the sea surface. The mean and maximum feeding durations were 14.5 ± 5.4 (SD; n = 58 events) and 32 s, respectively. Deployment of animal-borne data loggers yielded approximately 44 minutes of recordings from a single whale. The acceleration data showed that stroke rates, including tail beat and whole-body movements during feeding, were faster (approximately 0.7 s cycle) than during a cruising swim (approximately 3 s cycle) (Figure 1G). The swimming speed was lower than that in the stall speed (0.2 m s-1) of the device during the feeding phase, suggesting that thrust force was used to hold the head up and to stabilize body posture (Figure 1G). Stable positioning using the fluke and flipper was confirmed by video data for both the downward and upward direction of the whale (Figure S1). According to the visual and behavioral data, we named the head-lifting feeding as 'tread-water feeding'. Generally, all species of baleen whale, including rorqual whales, show active chasing and feeding, i.e., skimming, suction, and engulfing with lunging [1]. Tread-water feeding is considered passive feeding as compared with other feeding behaviors because the whales do not swim forward in pursuit of prey during the period from mouth opening to closing, and although they need thrust force to stabilize their posture, the head does not actively move. To the best of our knowledge, this discovery of tread-water feeding in Bryde's whales represents the first report of passive feeding in baleen whales, which indicates their flexible capacity to modify their foraging strategy in relation to variable environments.
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Affiliation(s)
- Takashi Iwata
- Atmosphere and Ocean Research Institute, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8564, Japan; Current addresses: Sea Mammal Research Unit, School of Biology, University of St Andrews, St Andrews, Fife, KY16 8LB, UK.
| | - Tomonari Akamatsu
- National Research Institute of Fisheries Science, Japan Fisheries Research and Education Agency, 2-12-4 Fukuura, Kanazawa, Yokohama, Kanagawa 236-8648, Japan
| | - Surasak Thongsukdee
- Marine and Coastal Resources Research and Development Center (The Upper Gulf of Thailand) 120/1 Moo 6 Bangyaprak, Mueang, Samut Sakhon, 74000, Thailand
| | - Phaothep Cherdsukjai
- Phuket Marine Biological Center - 51 Moo 8 Vichit, Mueang, Phuket, 83000, Thailand
| | - Kanjana Adulyanukosol
- Marine and Coastal Resources Research and Development Center (The Upper Gulf of Thailand) 120/1 Moo 6 Bangyaprak, Mueang, Samut Sakhon, 74000, Thailand
| | - Katsufumi Sato
- Atmosphere and Ocean Research Institute, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8564, Japan
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58
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Miller CT. Why marmosets? Dev Neurobiol 2018; 77:237-243. [PMID: 28170158 DOI: 10.1002/dneu.22483] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2016] [Revised: 01/05/2017] [Accepted: 01/05/2017] [Indexed: 12/17/2022]
Affiliation(s)
- Cory T Miller
- Cortical Systems and Behavior Laboratory, Neurosciences Graduate Program, University of California, San Diego, California
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59
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Szipl G, Ringler E, Bugnyar T. Attacked ravens flexibly adjust signalling behaviour according to audience composition. Proc Biol Sci 2018; 285:20180375. [PMID: 29875298 PMCID: PMC6015854 DOI: 10.1098/rspb.2018.0375] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2018] [Accepted: 05/16/2018] [Indexed: 11/12/2022] Open
Abstract
A fundamental attribute of social intelligence is the ability to monitor third-party relationships, which has been repeatedly demonstrated in primates, and recently also in captive ravens. It is yet unknown how ravens make use of this ability when dealing with different types of social relationships simultaneously during complex real-life situations. Free-ranging non-breeder ravens live in societies characterized by high fission-fusion dynamics and structured by age, pair-bond status and kinship. Here, we show that free-ranging ravens modify communication during conflicts according to audience composition. When being attacked by dominant conspecifics, victims of aggression signal their distress via defensive calls. Victims increased call rates when their kin were in the bystander audience, but reduced call rates when the bystanders were bonding partners of their aggressors. Hence, ravens use social knowledge flexibly and probably based on their own need (i.e. alert nearby allies and avoid alerting nearby rivals).
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Affiliation(s)
- Georgine Szipl
- Department of Cognitive Biology, University of Vienna, Althanstrasse 14, A-1090 Vienna, Austria
- Konrad Lorenz Research Station, Core Facility, University of Vienna, Fischerau 11, A-4645 Gruenau, Austria
| | - Eva Ringler
- Department of Integrative Zoology, University of Vienna, Althanstrasse 14, A-1090 Vienna, Austria
- Messerli Research Institute, University of Veterinary Medicine Vienna, Medical University of Vienna, and University of Vienna, Veterinaerplatz 1, A-1210 Vienna, Austria
| | - Thomas Bugnyar
- Department of Cognitive Biology, University of Vienna, Althanstrasse 14, A-1090 Vienna, Austria
- Konrad Lorenz Research Station, Core Facility, University of Vienna, Fischerau 11, A-4645 Gruenau, Austria
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60
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Lyamin OI, Kosenko PO, Korneva SM, Vyssotski AL, Mukhametov LM, Siegel JM. Fur Seals Suppress REM Sleep for Very Long Periods without Subsequent Rebound. Curr Biol 2018; 28:2000-2005.e2. [PMID: 29887309 DOI: 10.1016/j.cub.2018.05.022] [Citation(s) in RCA: 65] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2018] [Revised: 02/26/2018] [Accepted: 05/08/2018] [Indexed: 11/17/2022]
Abstract
Virtually all land mammals and birds have two sleep states: slow-wave sleep (SWS) and rapid eye movement (REM) sleep [1, 2]. After deprivation of REM sleep by repeated awakenings, mammals increase REM sleep time [3], supporting the idea that REM sleep is homeostatically regulated. Some evidence suggests that periods of REM sleep deprivation for a week or more cause physiological dysfunction and eventual death [4, 5]. However, separating the effects of REM sleep loss from the stress of repeated awakening is difficult [2, 6]. The northern fur seal (Callorhinus ursinus) is a semiaquatic mammal [7]. It can sleep on land and in seawater. The fur seal is unique in showing both the bilateral SWS seen in most mammals and the asymmetric sleep previously reported in cetaceans [8]. Here we show that when the fur seal stays in seawater, where it spends most of its life [7], it goes without or greatly reduces REM sleep for days or weeks. After this nearly complete elimination of REM, it displays minimal or no REM rebound upon returning to baseline conditions. Our data are consistent with the hypothesis that REM sleep may serve to reverse the reduced brain temperature and metabolism effects of bilateral nonREM sleep, a state that is greatly reduced when the fur seal is in the seawater, rather than REM sleep being directly homeostatically regulated. This can explain the absence of REM sleep in the dolphin and other cetaceans and its increasing proportion as the end of the sleep period approaches in humans and other mammals.
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Affiliation(s)
- Oleg I Lyamin
- Department of Psychiatry and Biobehavioral Sciences and Brain Research Institute, University of California, Los Angeles, Los Angeles, CA, USA; A.N. Severtsov Institute of Ecology and Evolution, RAS, Moscow, Russia; Utrish Dolphinarium, Moscow, Russia.
| | | | | | - Alexei L Vyssotski
- Institute of Neuroinformatics, University of Zurich and Swiss Federal Institute of Technology (ETH), Zurich, Switzerland
| | - Lev M Mukhametov
- A.N. Severtsov Institute of Ecology and Evolution, RAS, Moscow, Russia; Utrish Dolphinarium, Moscow, Russia
| | - Jerome M Siegel
- Department of Psychiatry and Biobehavioral Sciences and Brain Research Institute, University of California, Los Angeles, Los Angeles, CA, USA.
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61
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Lukas D, Clutton-Brock T. Social complexity and kinship in animal societies. Ecol Lett 2018; 21:1129-1134. [PMID: 29797749 DOI: 10.1111/ele.13079] [Citation(s) in RCA: 61] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2018] [Revised: 03/15/2018] [Accepted: 04/11/2018] [Indexed: 12/29/2022]
Abstract
Studies of eusocial invertebrates regard complex societies as those where there is a clear division of labour and extensive cooperation between breeders and helpers. In contrast, studies of social mammals identify complex societies as those where differentiated social relationships influence access to resources and reproductive opportunities. We show here that, while traits associated with social complexity of the first kind occur in social mammals that live in groups composed of close relatives, traits associated with the complexity of social relationships occur where average kinship between female group members is low. These differences in the form of social complexity appear to be associated with variation in brain size and probably reflect contrasts in the extent of conflicts of interest between group members. Our results emphasise the limitations of any unitary concept of social complexity and show that variation in average kinship between group members has far-reaching consequences for animal societies.
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Affiliation(s)
- Dieter Lukas
- Department of Zoology, University of Cambridge, Downing Street, CB2 3EJ, Cambridge, UK
| | - Tim Clutton-Brock
- Department of Zoology, University of Cambridge, Downing Street, CB2 3EJ, Cambridge, UK
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62
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Mahmud AI, Jaaman SA, Muda AM, Muhamad HM, Zhang X, Scapini F. Factors influencing the behaviour of Irrawaddy dolphins Orcaella brevirostris (Owen in Gray, 1866) in Brunei Bay, Malaysia. J ETHOL 2018. [DOI: 10.1007/s10164-018-0549-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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63
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Mori S, Matsunami M. Signature of positive selection in mitochondrial DNA in Cetartiodactyla. Genes Genet Syst 2018; 93:65-73. [PMID: 29643269 DOI: 10.1266/ggs.17-00015] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Acceleration of the amino acid substitution rate is a good indicator of positive selection in adaptive evolutionary changes of functional genes. Genomic information about mammals has become readily available in recent years, as many researchers have attempted to clarify the adaptive evolution of mammals by examining evolutionary rate change based on multiple loci. The order Cetartiodactyla (Artiodactyla and Cetacea) is one of the most diverse orders of mammals. Species in this order are found throughout all continents and seas, except Antarctica, and they exhibit wide variation in morphology and habitat. Here, we focused on the metabolism-related genes of mitochondrial DNA (mtDNA) in species of the order Cetartiodactyla using 191 mtDNA sequences available in databases. Based on comparisons of the dN/dS ratio (ω) in 12 protein-coding genes, ATP8 was shown to have a higher ω value (ω = 0.247) throughout Cetartiodactyla than the other 11 genes (ω < 0.05). In a branch-site analysis of ATP8 sequences, a markedly higher ω value of 0.801 was observed in the ancestral lineage of the clade of Cetacea, which is indicative of adaptive evolution. Through efforts to detect positively selected amino acids, codon positions 52 and 54 of ATP8 were shown to have experienced positive selective pressure during the course of evolution; multiple substitutions have occurred at these sites throughout the cetacean lineage. At position 52, glutamic acid was replaced with asparagine, and, at position 54, lysine was replaced with non-charged amino acids. These sites are conserved in most Artiodactyla. These results imply that the ancestor of cetaceans underwent accelerated amino acid changes in ATP8 and replacements at codons 52 and 54, which adjusted metabolism to adapt to the marine environment.
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Affiliation(s)
- Satoko Mori
- Laboratory of Ecology and Genetics, Graduate School of Environmental Science, Hokkaido University
| | - Masatoshi Matsunami
- Laboratory of Ecology and Genetics, Graduate School of Environmental Science, Hokkaido University.,Graduate School of Medicine, University of the Ryukyus
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64
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Vachon F, Whitehead H, Frasier TR. What factors shape genetic diversity in cetaceans? Ecol Evol 2018; 8:1554-1572. [PMID: 29435232 PMCID: PMC5792597 DOI: 10.1002/ece3.3727] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2017] [Revised: 11/07/2017] [Accepted: 11/20/2017] [Indexed: 01/01/2023] Open
Abstract
Understanding what factors drive patterns of genetic diversity is a central aspect of many biological questions, ranging from the inference of historical demography to assessing the evolutionary potential of a species. However, as a larger number of datasets have become available, it is becoming clear that the relationship between the characteristics of a species and its genetic diversity is more complex than previously assumed. This may be particularly true for cetaceans, due to their relatively long lifespans, long generation times, complex social structures, and extensive ranges. In this study, we used microsatellite and mitochondrial DNA data from a systematic literature review to produce estimates of diversity for both markers across 42 cetacean species. Factors relating to demography, distribution, classification, biology, and behavior were then tested using phylogenetic methods and linear models to assess their relative influence on the genetic diversity of both marker types. The results show that while relative nuclear diversity is correlated with population size, mitochondrial diversity is not. This is particularly relevant given the widespread use of mitochondrial DNA to infer historical demography. Instead, mitochondrial diversity was mostly influenced by the range and social structure of the species. In addition to population size, habitat type (neritic vs. oceanic) had a significant correlation with relative nuclear diversity. Combined, these results show that many often-unconsidered factors are likely influencing patterns of genetic diversity in cetaceans, with implications regarding how to interpret, and what can be inferred from, existing patterns of diversity.
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Affiliation(s)
- Felicia Vachon
- Department of BiologyDalhousie UniversityHalifaxNSCanada
| | - Hal Whitehead
- Department of BiologyDalhousie UniversityHalifaxNSCanada
| | - Timothy R. Frasier
- Department of Biology and Forensic Sciences ProgrammeSaint Mary's UniversityHalifaxNSCanada
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65
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Abstract
The brain is a dynamic organ of the biological renaissance due to the existence of neuroplasticity. Adult neurogenesis abides by every aspect of neuroplasticity in the intact brain and contributes to neural regeneration in response to brain diseases and injury. The occurrence of adult neurogenesis has unequivocally been witnessed in human subjects, experimental and wildlife research including rodents, bats and cetaceans. Adult neurogenesis is a complex cellular process, in which generation of neuroblasts namely, neuroblastosis appears to be an integral process that occur in the limbic system and basal ganglia in addition to the canonical neurogenic niches. Neuroblastosis can be regulated by various factors and contributes to different functions of the brain. The characteristics and fate of neuroblasts have been found to be different among mammals regardless of their cognitive functions. Recently, regulation of neuroblastosis has been proposed for the sensorimotor interface and regenerative neuroplasticity of the adult brain. Hence, the understanding of adult neurogenesis at the functional level of neuroblasts requires a great scientific attention. Therefore, this mini-review provides a glimpse into the conceptual development of neuroplasticity, discusses the possible role of different types of neuroblasts and signifies neuroregenerative failure as a potential cause of dementia.
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Affiliation(s)
- Mahesh Kandasamy
- Laboratory of Stem Cells and Neuroregeneration, Department of Animal Science, School of Life Sciences, Bharathidasan University, Tiruchirappalli, Tamil Nadu; Faculty Recharge Programme, University Grants Commission (UGC-FRP), New Delhi, India
| | - Ludwig Aigner
- Institute of Molecular Regenerative Medicine, Salzburg, Paracelsus Medical University; Spinal Cord Injury and Tissue Regeneration Center, Salzburg, Paracelsus Medical University, Salzburg, Austria
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66
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Fox KCR, Muthukrishna M, Shultz S. The social and cultural roots of whale and dolphin brains. Nat Ecol Evol 2017; 1:1699-1705. [PMID: 29038481 DOI: 10.1038/s41559-017-0336-y] [Citation(s) in RCA: 66] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2016] [Accepted: 09/01/2017] [Indexed: 02/04/2023]
Abstract
Encephalization, or brain expansion, underpins humans' sophisticated social cognition, including language, joint attention, shared goals, teaching, consensus decision-making and empathy. These abilities promote and stabilize cooperative social interactions, and have allowed us to create a 'cognitive' or 'cultural' niche and colonize almost every terrestrial ecosystem. Cetaceans (whales and dolphins) also have exceptionally large and anatomically sophisticated brains. Here, by evaluating a comprehensive database of brain size, social structures and cultural behaviours across cetacean species, we ask whether cetacean brains are similarly associated with a marine cultural niche. We show that cetacean encephalization is predicted by both social structure and by a quadratic relationship with group size. Moreover, brain size predicts the breadth of social and cultural behaviours, as well as ecological factors (diversity of prey types and to a lesser extent latitudinal range). The apparent coevolution of brains, social structure and behavioural richness of marine mammals provides a unique and striking parallel to the large brains and hyper-sociality of humans and other primates. Our results suggest that cetacean social cognition might similarly have arisen to provide the capacity to learn and use a diverse set of behavioural strategies in response to the challenges of social living.
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Affiliation(s)
- Kieran C R Fox
- Department of Neurology and Neurological Sciences, Stanford University, Stanford, CA, 94305, USA
| | - Michael Muthukrishna
- Department of Psychological and Behavioural Science, London School of Economics and Political Science, London, WC2A 2AE, UK.,Department of Human Evolutionary Biology, Harvard University, Cambridge, MA, 02138, USA
| | - Susanne Shultz
- School of Earth and Environmental Sciences, University of Manchester, Manchester, M13 9PL, UK.
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Xu S, Sun X, Niu X, Zhang Z, Tian R, Ren W, Zhou K, Yang G. Genetic basis of brain size evolution in cetaceans: insights from adaptive evolution of seven primary microcephaly (MCPH) genes. BMC Evol Biol 2017; 17:206. [PMID: 28851290 PMCID: PMC5576371 DOI: 10.1186/s12862-017-1051-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2017] [Accepted: 08/14/2017] [Indexed: 12/29/2022] Open
Abstract
BACKGROUND Cetacean brain size expansion is an enigmatic event in mammalian evolution, yet its genetic basis remains poorly explored. Here, all exons of the seven primary microcephaly (MCPH) genes that play key roles in size regulation during brain development were investigated in representative cetacean lineages. RESULTS Sequences of MCPH2-7 genes were intact in cetaceans but frameshift mutations and stop codons was identified in MCPH1. Extensive positive selection was identified in four of six intact MCPH genes: WDR62, CDK5RAP2, CEP152, and ASPM. Specially, positive selection at CDK5RAP2 and ASPM were examined along lineages of odontocetes with increased encephalization quotients (EQ) and mysticetes with reduced EQ but at WDR62 only found along odontocete lineages. Interestingly, a positive association between evolutionary rate (ω) and EQ was identified for CDK5RAP2 and ASPM. Furthermore, we tested the binding affinities between Calmodulin (CaM) and ASPM IQ motif in cetaceans because only CaM combined with IQ, can ASPM perform the function in determining brain size. Preliminary function assay showed binding affinities between CaM and IQ motif of the odontocetes with increased EQ was stronger than for the mysticetes with decreased EQ. In addition, evolution rate of ASPM and CDK5RAP2 were significantly related to mean group size (as one measure of social complexity). CONCLUSIONS Our study investigated the genetic basis of cetacean brain size evolution. Significant positive selection was examined along lineages with both increased and decreased EQ at CDK5RAP2 and ASPM, which is well matched with cetacean complex brain size evolution. Evolutionary rate of CDK5RAP2 and ASPM were significantly related to EQ, suggesting that these two genes may have contributed to EQ expansion in cetaceans. This suggestion was further indicated by our preliminary function test that ASPM might be mainly linked to evolutionary increases in EQ. Most strikingly, our results suggested that cetaceans evolved large brains to manage complex social systems, consisting with the 'social brain hypothesis', as evolutionary rate of ASPM and CDK5RAP2 were significantly related to mean group size.
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Affiliation(s)
- Shixia Xu
- Jiangsu Key Laboratory for Biodiversity and Biotechnology, College of Life Sciences, Nanjing Normal University, 1 Wenyuan Road, Nanjing, 210023 China
| | - Xiaohui Sun
- Jiangsu Key Laboratory for Biodiversity and Biotechnology, College of Life Sciences, Nanjing Normal University, 1 Wenyuan Road, Nanjing, 210023 China
| | - Xu Niu
- Jiangsu Key Laboratory for Biodiversity and Biotechnology, College of Life Sciences, Nanjing Normal University, 1 Wenyuan Road, Nanjing, 210023 China
| | - Zepeng Zhang
- Jiangsu Key Laboratory for Biodiversity and Biotechnology, College of Life Sciences, Nanjing Normal University, 1 Wenyuan Road, Nanjing, 210023 China
| | - Ran Tian
- Jiangsu Key Laboratory for Biodiversity and Biotechnology, College of Life Sciences, Nanjing Normal University, 1 Wenyuan Road, Nanjing, 210023 China
| | - Wenhua Ren
- Jiangsu Key Laboratory for Biodiversity and Biotechnology, College of Life Sciences, Nanjing Normal University, 1 Wenyuan Road, Nanjing, 210023 China
| | - Kaiya Zhou
- Jiangsu Key Laboratory for Biodiversity and Biotechnology, College of Life Sciences, Nanjing Normal University, 1 Wenyuan Road, Nanjing, 210023 China
| | - Guang Yang
- Jiangsu Key Laboratory for Biodiversity and Biotechnology, College of Life Sciences, Nanjing Normal University, 1 Wenyuan Road, Nanjing, 210023 China
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Rambaldi A, Cozzi B, Grandis A, Canova M, Mazzoni M, Bombardi C. Distribution of Calretinin Immunoreactivity in the Lateral Nucleus of the Bottlenose Dolphin (Tursiops truncatus
) Amygdala. Anat Rec (Hoboken) 2017; 300:2008-2016. [DOI: 10.1002/ar.23634] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2016] [Revised: 04/05/2017] [Accepted: 04/06/2017] [Indexed: 01/13/2023]
Affiliation(s)
- A.M. Rambaldi
- Department of Veterinary Medical Sciences (UNI EN ISO 9001:2008); University of Bologna; Bologna Italy
| | - B. Cozzi
- Department of Comparative Biomedicine and Food Science; University of Padova; Padova Italy
| | - A. Grandis
- Department of Veterinary Medical Sciences (UNI EN ISO 9001:2008); University of Bologna; Bologna Italy
| | - M. Canova
- Department of Veterinary Medical Sciences (UNI EN ISO 9001:2008); University of Bologna; Bologna Italy
| | - M. Mazzoni
- Department of Veterinary Medical Sciences (UNI EN ISO 9001:2008); University of Bologna; Bologna Italy
| | - C. Bombardi
- Department of Veterinary Medical Sciences (UNI EN ISO 9001:2008); University of Bologna; Bologna Italy
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Abramson JZ, Hernández-Lloreda MV, Esteban JA, Colmenares F, Aboitiz F, Call J. Contextual imitation of intransitive body actions in a Beluga whale (Delphinapterus leucas): A "do as other does" study. PLoS One 2017. [PMID: 28636677 PMCID: PMC5479519 DOI: 10.1371/journal.pone.0178906] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Cetaceans are remarkable for exhibiting group-specific behavioral traditions or cultures in several behavioral domains (e.g., calls, behavioral tactics), and the question of whether they can be acquired socially, for example through imitative processes, remains open. Here we used a “Do as other does” paradigm to experimentally study the ability of a beluga to imitate familiar intransitive (body-oriented) actions demonstrated by a conspecific. The participant was first trained to copy three familiar behaviors on command (training phase) and then was tested for her ability to generalize the learned “Do as the other does” command to a different set of three familiar behaviors (testing phase). We found that the beluga (1) was capable of learning the copy command signal “Do what-the-other-does”; (2) exhibited high matching accuracy for trained behaviors (mean = 84% of correct performance) after making the first successful copy on command; (3) copied successfully the new set of three familiar generalization behaviors that were untrained to the copy command (range of first copy = 12 to 35 trials); and (4) deployed a high level of matching accuracy (mean = 83%) after making the first copy of an untrained behavior on command. This is the first evidence of contextual imitation of intransitive (body-oriented) movements in the beluga and adds to the reported findings on production imitation of sounds in this species and production imitation of sounds and motor actions in several cetaceans, especially dolphins and killer whales. Collectively these findings highlight the notion that cetaceans have a natural propensity at skillfully and proficiently matching the sounds and body movements demonstrated by conspecifics, a fitness-enhancing propensity in the context of cooperative hunting and anti-predatory defense tactics, and of alliance formation strategies that have been documented in these species’ natural habitats. Future work should determine if the beluga can also imitate novel motor actions.
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Affiliation(s)
- José Z. Abramson
- Departamento de Psiquiatría, Facultad de Medicina, y Centro Interdisciplinario de Neurociencia, Pontificia Universidad Católica de Chile, Santiago, Chile
- Centro de Estudios Avanzados, Universidad de Playa Ancha, Valparaíso, Chile
- Grupo UCM de Estudio del Comportamiento Animal y Humano Universidad Complutense de Madrid, Madrid, Spain
- * E-mail:
| | - Mª Victoria Hernández-Lloreda
- Grupo UCM de Estudio del Comportamiento Animal y Humano Universidad Complutense de Madrid, Madrid, Spain
- Departamento de Metodología de las Ciencias del Comportamiento, Facultad de Psicología, Campus de Somosaguas, Universidad Complutense de Madrid, Madrid, Spain
| | - José-Antonio Esteban
- Research Department, Parques Reunidos Valencia S. A. Oceanogràfic, Ciudad de las Artes y las Ciencias, Valencia, Spain
| | - Fernando Colmenares
- Grupo UCM de Estudio del Comportamiento Animal y Humano Universidad Complutense de Madrid, Madrid, Spain
- Departamento de Psicobiología, Facultad de Psicología, Campus de Somosaguas, Universidad Complutense de Madrid, Madrid, Spain
| | - Francisco Aboitiz
- Departamento de Psiquiatría, Facultad de Medicina, y Centro Interdisciplinario de Neurociencia, Pontificia Universidad Católica de Chile, Santiago, Chile
| | - Josep Call
- School of Psychology and Neuroscience, University of St Andrews, St Mary’s Quad, South Street, St Andrews, Fife KY, United Kingdom
- Department of Developmental and Comparative Psychology, Max-Planck Institute for Evolutionary Anthropology, Deutscher Platz 6, Leipzig, Germany
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Mikhalevich I, Powell R, Logan C. Is behavioural flexibility evidence of cognitive complexity? How evolution can inform comparative cognition. Interface Focus 2017; 7:20160121. [PMID: 28479981 PMCID: PMC5413892 DOI: 10.1098/rsfs.2016.0121] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Behavioural flexibility is often treated as the gold standard of evidence for more sophisticated or complex forms of animal cognition, such as planning, metacognition and mindreading. However, the evidential link between behavioural flexibility and complex cognition has not been explicitly or systematically defended. Such a defence is particularly pressing because observed flexible behaviours can frequently be explained by putatively simpler cognitive mechanisms. This leaves complex cognition hypotheses open to 'deflationary' challenges that are accorded greater evidential weight precisely because they offer putatively simpler explanations of equal explanatory power. This paper challenges the blanket preference for simpler explanations, and shows that once this preference is dispensed with, and the full spectrum of evidence-including evolutionary, ecological and phylogenetic data-is accorded its proper weight, an argument in support of the prevailing assumption that behavioural flexibility can serve as evidence for complex cognitive mechanisms may begin to take shape. An adaptive model of cognitive-behavioural evolution is proposed, according to which the existence of convergent trait-environment clusters in phylogenetically disparate lineages may serve as evidence for the same trait-environment clusters in other lineages. This, in turn, could permit inferences of cognitive complexity in cases of experimental underdetermination, thereby placing the common view that behavioural flexibility can serve as evidence for complex cognition on firmer grounds.
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Affiliation(s)
- Irina Mikhalevich
- School of Mind and Brain, Humboldt-Universitat zu Berlin, Berlin, Germany
| | - Russell Powell
- Department of Philosophy, Boston University, Boston, MA 02215, USA
| | - Corina Logan
- Department of Zoology, University of Cambridge, Cambridge, UK
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71
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Pérez-Manrique A, Gomila A. The comparative study of empathy: sympathetic concern and empathic perspective-taking in non-human animals. Biol Rev Camb Philos Soc 2017; 93:248-269. [DOI: 10.1111/brv.12342] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2016] [Revised: 04/25/2017] [Accepted: 05/03/2017] [Indexed: 12/20/2022]
Affiliation(s)
- Ana Pérez-Manrique
- Department of Psychology; Human Evolution and Cognition Group (EvoCog), UIB, IFISC, Associated Unit to CSIC; 07122 Palma Spain
| | - Antoni Gomila
- Department of Psychology; Human Evolution and Cognition Group (EvoCog), UIB, IFISC, Associated Unit to CSIC; 07122 Palma Spain
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72
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Dale R, Plotnik JM. Elephants know when their bodies are obstacles to success in a novel transfer task. Sci Rep 2017; 7:46309. [PMID: 28402335 PMCID: PMC5389349 DOI: 10.1038/srep46309] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2016] [Accepted: 03/14/2017] [Indexed: 11/19/2022] Open
Abstract
The capacity to recognise oneself as separate from other individuals and objects is difficult to investigate in non-human animals. The hallmark empirical assessment, the mirror self-recognition test, focuses on an animal's ability to recognise itself in a mirror and success has thus far been demonstrated in only a small number of species with a keen interest in their own visual reflection. Adapting a recent study done with children, we designed a new body-awareness paradigm for testing an animal's understanding of its place in its environment. In this task, Asian elephants (Elephas maximus) were required to step onto a mat and pick up a stick attached to it by rope, and then pass the stick forward to an experimenter. In order to do the latter, the elephants had to see their body as an obstacle to success and first remove their weight from the mat before attempting to transfer the stick. The elephants got off the mat in the test significantly more often than in controls, where getting off the mat was unnecessary. This task helps level the playing field for non-visual species tested on cognition tasks and may help better define the continuum on which body- and self-awareness lie.
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Affiliation(s)
- Rachel Dale
- Think Elephants International, Stone Ridge, NY, USA
| | - Joshua M. Plotnik
- Think Elephants International, Stone Ridge, NY, USA
- Dept. of Psychology, University of Cambridge, Cambridge, UK
- Mahidol University–Kanchanaburi, Sai Yok, Kanchanaburi, Thailand
- Golden Triangle Asian Elephant Foundation, Chiang Saen, Thailand
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73
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Clegg IL, Rödel HG, Delfour F. Bottlenose dolphins engaging in more social affiliative behaviour judge ambiguous cues more optimistically. Behav Brain Res 2017; 322:115-122. [DOI: 10.1016/j.bbr.2017.01.026] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2017] [Accepted: 01/13/2017] [Indexed: 10/20/2022]
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74
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Ridgway SH, Carlin KP, Van Alstyne KR, Hanson AC, Tarpley RJ. Comparison of Dolphins' Body and Brain Measurements with Four Other Groups of Cetaceans Reveals Great Diversity. BRAIN, BEHAVIOR AND EVOLUTION 2017; 88:235-257. [PMID: 28122370 DOI: 10.1159/000454797] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2016] [Accepted: 11/28/2016] [Indexed: 01/06/2023]
Abstract
We compared mature dolphins with 4 other groupings of mature cetaceans. With a large data set, we found great brain diversity among 5 different taxonomic groupings. The dolphins in our data set ranged in body mass from about 40 to 6,750 kg and in brain mass from 0.4 to 9.3 kg. Dolphin body length ranged from 1.3 to 7.6 m. In our combined data set from the 4 other groups of cetaceans, body mass ranged from about 20 to 120,000 kg and brain mass from about 0.2 to 9.2 kg, while body length varied from 1.21 to 26.8 m. Not all cetaceans have large brains relative to their body size. A few dolphins near human body size have human-sized brains. On the other hand, the absolute brain mass of some other cetaceans is only one-sixth as large. We found that brain volume relative to body mass decreases from Delphinidae to a group of Phocoenidae and Monodontidae, to a group of other odontocetes, to Balaenopteroidea, and finally to Balaenidae. We also found the same general trend when we compared brain volume relative to body length, except that the Delphinidae and Phocoenidae-Monodontidae groups do not differ significantly. The Balaenidae have the smallest relative brain mass and the lowest cerebral cortex surface area. Brain parts also vary. Relative to body mass and to body length, dolphins also have the largest cerebellums. Cortex surface area is isometric with brain size when we exclude the Balaenidae. Our data show that the brains of Balaenidae are less convoluted than those of the other cetaceans measured. Large vascular networks inside the cranial vault may help to maintain brain temperature, and these nonbrain tissues increase in volume with body mass and with body length ranging from 8 to 65% of the endocranial volume. Because endocranial vascular networks and other adnexa, such as the tentorium cerebelli, vary so much in different species, brain size measures from endocasts of some extinct cetaceans may be overestimates. Our regression of body length on endocranial adnexa might be used for better estimates of brain volume from endocasts or from endocranial volume of living species or extinct cetaceans.
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Affiliation(s)
- Sam H Ridgway
- National Marine Mammal Foundation, San Diego, CA, USA
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75
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Broadway MS, Samuelson MM, Christopher JL, Jett SE, Lyn H. Does size really matter? Investigating cognitive differences in spatial memory ability based on size in domestic dogs. Behav Processes 2017; 138:7-14. [PMID: 28119017 DOI: 10.1016/j.beproc.2017.01.012] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2016] [Revised: 10/11/2016] [Accepted: 01/18/2017] [Indexed: 01/08/2023]
Abstract
The study of canine cognition can be useful in understanding the selective pressures affecting cognitive abilities. Dogs have undergone intensive artificial selection yielding distinctive breeds, which differ both phenotypically and behaviorally and no other species has a wider range in brain size. As brain size has long been hypothesized to relate to cognitive capacity, this species offers a useful model to further explore this relationship. The influence of physical size on canine cognition has not been thoroughly addressed, despite the fact that large dogs are often perceived to be 'smarter' than small dogs. To date, this preconception has only recently been addressed and supported in one study comparing large and small dogs in a social cognition task, where large dogs outperformed small dogs in a pointing choice task. We assessed large and small dogs using a series of spatial cognition tasks and detected no differences between the two groups. Further research is needed to clarify why our results failed to compliment previous findings. It is possible that differences found in social cognition tasks may not be due to differences in size, rather they may be based on other factors such as methodology, prior training experience, or past experience with humans in general.
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Affiliation(s)
- Megan S Broadway
- The University of Southern Mississippi,730 East Beach Blvd., Long Beach, MS 39560, United States.
| | - Mystera M Samuelson
- The University of Southern Mississippi,730 East Beach Blvd., Long Beach, MS 39560, United States
| | - Jennie L Christopher
- The University of Southern Mississippi,730 East Beach Blvd., Long Beach, MS 39560, United States
| | - Stephanie E Jett
- The University of Southern Mississippi,730 East Beach Blvd., Long Beach, MS 39560, United States
| | - Heidi Lyn
- The University of Southern Mississippi,730 East Beach Blvd., Long Beach, MS 39560, United States
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76
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Steinhausen C, Zehl L, Haas-Rioth M, Morcinek K, Walkowiak W, Huggenberger S. Multivariate Meta-Analysis of Brain-Mass Correlations in Eutherian Mammals. Front Neuroanat 2016; 10:91. [PMID: 27746724 PMCID: PMC5043137 DOI: 10.3389/fnana.2016.00091] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2016] [Accepted: 09/13/2016] [Indexed: 11/26/2022] Open
Abstract
The general assumption that brain size differences are an adequate proxy for subtler differences in brain organization turned neurobiologists toward the question why some groups of mammals such as primates, elephants, and whales have such remarkably large brains. In this meta-analysis, an extensive sample of eutherian mammals (115 species distributed in 14 orders) provided data about several different biological traits and measures of brain size such as absolute brain mass (AB), relative brain mass (RB; quotient from AB and body mass), and encephalization quotient (EQ). These data were analyzed by established multivariate statistics without taking specific phylogenetic information into account. Species with high AB tend to (1) feed on protein-rich nutrition, (2) have a long lifespan, (3) delayed sexual maturity, and (4) long and rare pregnancies with small litter sizes. Animals with high RB usually have (1) a short life span, (2) reach sexual maturity early, and (3) have short and frequent gestations. Moreover, males of species with high RB also have few potential sexual partners. In contrast, animals with high EQs have (1) a high number of potential sexual partners, (2) delayed sexual maturity, and (3) rare gestations with small litter sizes. Based on these correlations, we conclude that Eutheria with either high AB or high EQ occupy positions at the top of the network of food chains (high trophic levels). Eutheria of low trophic levels can develop a high RB only if they have small body masses.
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Affiliation(s)
- Charlene Steinhausen
- Department II of Anatomy, University of CologneCologne, Germany
- Biocenter, University of CologneCologne, Germany
| | - Lyuba Zehl
- Biocenter, University of CologneCologne, Germany
- Jülich Research Centre, Institute of Neuroscience and Medicine (INM-6) and Institute for Advanced Simulation (IAS-6) and JARA BRAIN Institute IJülich, Germany
| | - Michaela Haas-Rioth
- Department of Anatomy III (Dr. Senckenbergische Anatomie), Goethe University of Frankfurt am MainFrankfurt am Main, Germany
| | | | | | - Stefan Huggenberger
- Department II of Anatomy, University of CologneCologne, Germany
- Biocenter, University of CologneCologne, Germany
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77
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Berns GS, Cook PF, Foxley S, Jbabdi S, Miller KL, Marino L. Diffusion tensor imaging of dolphin brains reveals direct auditory pathway to temporal lobe. Proc Biol Sci 2016; 282:rspb.2015.1203. [PMID: 26156774 PMCID: PMC4528565 DOI: 10.1098/rspb.2015.1203] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
The brains of odontocetes (toothed whales) look grossly different from their terrestrial relatives. Because of their adaptation to the aquatic environment and their reliance on echolocation, the odontocetes' auditory system is both unique and crucial to their survival. Yet, scant data exist about the functional organization of the cetacean auditory system. A predominant hypothesis is that the primary auditory cortex lies in the suprasylvian gyrus along the vertex of the hemispheres, with this position induced by expansion of 'associative' regions in lateral and caudal directions. However, the precise location of the auditory cortex and its connections are still unknown. Here, we used a novel diffusion tensor imaging (DTI) sequence in archival post-mortem brains of a common dolphin (Delphinus delphis) and a pantropical dolphin (Stenella attenuata) to map their sensory and motor systems. Using thalamic parcellation based on traditionally defined regions for the primary visual (V1) and auditory cortex (A1), we found distinct regions of the thalamus connected to V1 and A1. But in addition to suprasylvian-A1, we report here, for the first time, the auditory cortex also exists in the temporal lobe, in a region near cetacean-A2 and possibly analogous to the primary auditory cortex in related terrestrial mammals (Artiodactyla). Using probabilistic tract tracing, we found a direct pathway from the inferior colliculus to the medial geniculate nucleus to the temporal lobe near the sylvian fissure. Our results demonstrate the feasibility of post-mortem DTI in archival specimens to answer basic questions in comparative neurobiology in a way that has not previously been possible and shows a link between the cetacean auditory system and those of terrestrial mammals. Given that fresh cetacean specimens are relatively rare, the ability to measure connectivity in archival specimens opens up a plethora of possibilities for investigating neuroanatomy in cetaceans and other species.
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Affiliation(s)
| | - Peter F Cook
- Psychology Department, Emory University, Atlanta, GA, USA
| | - Sean Foxley
- FMRIB Centre, University of Oxford, Oxford, UK
| | - Saad Jbabdi
- FMRIB Centre, University of Oxford, Oxford, UK
| | | | - Lori Marino
- The Kimmela Center for Animal Advocacy, Kanab, UT, USA
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79
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The Evolution of Brains and Cognitive Abilities. Evol Biol 2016. [DOI: 10.1007/978-3-319-41324-2_5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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80
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Gero S, Whitehead H, Rendell L. Individual, unit and vocal clan level identity cues in sperm whale codas. ROYAL SOCIETY OPEN SCIENCE 2016; 3:150372. [PMID: 26909165 PMCID: PMC4736920 DOI: 10.1098/rsos.150372] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2015] [Accepted: 12/03/2015] [Indexed: 05/09/2023]
Abstract
The 'social complexity hypothesis' suggests that complex social structure is a driver of diversity in animal communication systems. Sperm whales have a hierarchically structured society in which the largest affiliative structures, the vocal clans, are marked on ocean-basin scales by culturally transmitted dialects of acoustic signals known as 'codas'. We examined variation in coda repertoires among both individual whales and social units-the basic element of sperm whale society-using data from nine Caribbean social units across six years. Codas were assigned to individuals using photo-identification and acoustic size measurement, and we calculated similarity between repertoires using both continuous and categorical methods. We identified 21 coda types. Two of those ('1+1+3' and '5R1') made up 65% of the codas recorded, were shared across all units and have dominated repertoires in this population for at least 30 years. Individuals appear to differ in the way they produce '5R1' but not '1+1+3' coda. Units use distinct 4-click coda types which contribute to making unit repertoires distinctive. Our results support the social complexity hypothesis in a marine species as different patterns of variation between coda types suggest divergent functions, perhaps representing selection for identity signals at several levels of social structure.
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Affiliation(s)
- Shane Gero
- Zoophysiology, Department of Bioscience, Aarhus University, Aarhus, Jutland, Denmark
- Department of Biology, Dalhousie University, Halifax, Canada B3H 4J1
- Centre for Social Learning and Cognitive Evolution, and Sea Mammal Research Unit, School of Biology, University of St Andrews, St Andrews KY16 9TH, UK
- Author for correspondence: Shane Gero e-mail:
| | - Hal Whitehead
- Department of Biology, Dalhousie University, Halifax, Canada B3H 4J1
| | - Luke Rendell
- Centre for Social Learning and Cognitive Evolution, and Sea Mammal Research Unit, School of Biology, University of St Andrews, St Andrews KY16 9TH, UK
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Tsagkogeorga G, McGowen MR, Davies KTJ, Jarman S, Polanowski A, Bertelsen MF, Rossiter SJ. A phylogenomic analysis of the role and timing of molecular adaptation in the aquatic transition of cetartiodactyl mammals. ROYAL SOCIETY OPEN SCIENCE 2015; 2:150156. [PMID: 26473040 PMCID: PMC4593674 DOI: 10.1098/rsos.150156] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/21/2015] [Accepted: 09/02/2015] [Indexed: 05/30/2023]
Abstract
Recent studies have reported multiple cases of molecular adaptation in cetaceans related to their aquatic abilities. However, none of these has included the hippopotamus, precluding an understanding of whether molecular adaptations in cetaceans occurred before or after they split from their semi-aquatic sister taxa. Here, we obtained new transcriptomes from the hippopotamus and humpback whale, and analysed these together with available data from eight other cetaceans. We identified more than 11 000 orthologous genes and compiled a genome-wide dataset of 6845 coding DNA sequences among 23 mammals, to our knowledge the largest phylogenomic dataset to date for cetaceans. We found positive selection in nine genes on the branch leading to the common ancestor of hippopotamus and whales, and 461 genes in cetaceans compared to 64 in hippopotamus. Functional annotation revealed adaptations in diverse processes, including lipid metabolism, hypoxia, muscle and brain function. By combining these findings with data on protein-protein interactions, we found evidence suggesting clustering among gene products relating to nervous and muscular systems in cetaceans. We found little support for shared ancestral adaptations in the two taxa; most molecular adaptations in extant cetaceans occurred after their split with hippopotamids.
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Affiliation(s)
- Georgia Tsagkogeorga
- School of Biological and Chemical Sciences, Queen Mary University of London, Mile End Road, London E1 4NS, UK
| | - Michael R. McGowen
- School of Biological and Chemical Sciences, Queen Mary University of London, Mile End Road, London E1 4NS, UK
| | - Kalina T. J. Davies
- School of Biological and Chemical Sciences, Queen Mary University of London, Mile End Road, London E1 4NS, UK
| | - Simon Jarman
- Australian Antarctic Division, Channel Highway, Kingston, Tasmania 7050, Australia
| | - Andrea Polanowski
- Australian Antarctic Division, Channel Highway, Kingston, Tasmania 7050, Australia
| | - Mads F. Bertelsen
- Center for Zoo and Wild Animal Health, Copenhagen Zoo, Roskildevej 38, Frederiksberg 2000, Denmark
| | - Stephen J. Rossiter
- School of Biological and Chemical Sciences, Queen Mary University of London, Mile End Road, London E1 4NS, UK
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82
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Gero S, Gordon J, Whitehead H. Individualized social preferences and long-term social fidelity between social units of sperm whales. Anim Behav 2015. [DOI: 10.1016/j.anbehav.2015.01.008] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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83
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84
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Vollmer N, Hayek LA, Heithaus M, Connor R. Further evidence of a context-specific agonistic signal in bottlenose dolphins: the influence of consortships and group size on the pop vocalization. BEHAVIOUR 2015. [DOI: 10.1163/1568539x-00003311] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Pops are a low-frequency, pulsed vocalization produced by Indo-Pacific bottlenose dolphins (Tursiopscf.aduncus) in Shark Bay, Western Australia and are often heard when male alliances are consorting or ‘herding’ a female. Previous research indicated that pops produced in this context are an agonistic ‘come-hither’ demand produced by males and directed at female consorts. Here we examine pop occurrence during focal follows on bottlenose dolphin alliances with and without female consorts present. Regression analysis was conducted to determine if pop numbers were higher in the presence of female consorts, and if variables including group size alone and the interaction between presence/absence of a consortship and group size, influenced pop production. While the presence or absence of a consortship significantly affected the number of pops, average group size had no significant effect on pop production. Our research provides further evidence that the pop vocalization plays an important role in consortships.
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Affiliation(s)
- Nicole L. Vollmer
- National Systematics Laboratory, National Marine Fisheries Service, NOAA, Smithsonian Institution, PO Box 37012, Washington, DC 20013, USA
| | - Lee-Ann C. Hayek
- Smithsonian Institution, Mathematics and Statistics, MRC-121, PO Box 37012, Washington, DC 20013, USA
| | - Michael R. Heithaus
- Department of Biological Sciences, Florida International University, 3000 NE 151 St., North Miami, FL 33181, USA
| | - Richard C. Connor
- Department of Biology, UMASS-Dartmouth, 285 Old Westport Road, North Dartmouth, MA 02747, USA
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85
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Mortensen HS, Pakkenberg B, Dam M, Dietz R, Sonne C, Mikkelsen B, Eriksen N. Quantitative relationships in delphinid neocortex. Front Neuroanat 2014; 8:132. [PMID: 25505387 PMCID: PMC4244864 DOI: 10.3389/fnana.2014.00132] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2014] [Accepted: 10/29/2014] [Indexed: 12/04/2022] Open
Abstract
Possessing large brains and complex behavioral patterns, cetaceans are believed to be highly intelligent. Their brains, which are the largest in the Animal Kingdom and have enormous gyrification compared with terrestrial mammals, have long been of scientific interest. Few studies, however, report total number of brain cells in cetaceans, and even fewer have used unbiased counting methods. In this study, using stereological methods, we estimated the total number of cells in the neocortex of the long-finned pilot whale (Globicephala melas) brain. For the first time, we show that a species of dolphin has more neocortical neurons than any mammal studied to date including humans. These cell numbers are compared across various mammals with different brain sizes, and the function of possessing many neurons is discussed. We found that the long-finned pilot whale neocortex has approximately 37.2 × 109 neurons, which is almost twice as many as humans, and 127 × 109 glial cells. Thus, the absolute number of neurons in the human neocortex is not correlated with the superior cognitive abilities of humans (at least compared to cetaceans) as has previously been hypothesized. However, as neuron density in long-finned pilot whales is lower than that in humans, their higher cell number appears to be due to their larger brain. Accordingly, our findings make an important contribution to the ongoing debate over quantitative relationships in the mammalian brain.
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Affiliation(s)
- Heidi S Mortensen
- Research Laboratory for Stereology and Neuroscience, Bispebjerg and Frederiksberg University Hospitals Copenhagen, Denmark ; Research Department, Environment Agency Torshavn, Faroe Islands
| | - Bente Pakkenberg
- Research Laboratory for Stereology and Neuroscience, Bispebjerg and Frederiksberg University Hospitals Copenhagen, Denmark
| | - Maria Dam
- Research Department, Environment Agency Torshavn, Faroe Islands
| | - Rune Dietz
- Department of Bioscience, Institute for Bioscience - Arctic Research Centre, Roskilde, University of Aarhus Roskilde, Denmark
| | - Christian Sonne
- Department of Bioscience, Institute for Bioscience - Arctic Research Centre, Roskilde, University of Aarhus Roskilde, Denmark
| | | | - Nina Eriksen
- Research Laboratory for Stereology and Neuroscience, Bispebjerg and Frederiksberg University Hospitals Copenhagen, Denmark
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86
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Reisinger RR, Oosthuizen WC, Péron G, Cory Toussaint D, Andrews RD, de Bruyn PJN. Satellite tagging and biopsy sampling of killer whales at subantarctic Marion Island: effectiveness, immediate reactions and long-term responses. PLoS One 2014; 9:e111835. [PMID: 25375329 PMCID: PMC4222950 DOI: 10.1371/journal.pone.0111835] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2014] [Accepted: 10/01/2014] [Indexed: 11/19/2022] Open
Abstract
Remote tissue biopsy sampling and satellite tagging are becoming widely used in large marine vertebrate studies because they allow the collection of a diverse suite of otherwise difficult-to-obtain data which are critical in understanding the ecology of these species and to their conservation and management. Researchers must carefully consider their methods not only from an animal welfare perspective, but also to ensure the scientific rigour and validity of their results. We report methods for shore-based, remote biopsy sampling and satellite tagging of killer whales Orcinus orca at Subantarctic Marion Island. The performance of these methods is critically assessed using 1) the attachment duration of low-impact minimally percutaneous satellite tags; 2) the immediate behavioural reactions of animals to biopsy sampling and satellite tagging; 3) the effect of researcher experience on biopsy sampling and satellite tagging; and 4) the mid- (1 month) and long- (24 month) term behavioural consequences. To study mid- and long-term behavioural changes we used multievent capture-recapture models that accommodate imperfect detection and individual heterogeneity. We made 72 biopsy sampling attempts (resulting in 32 tissue samples) and 37 satellite tagging attempts (deploying 19 tags). Biopsy sampling success rates were low (43%), but tagging rates were high with improved tag designs (86%). The improved tags remained attached for 26±14 days (mean ± SD). Individuals most often showed no reaction when attempts missed (66%) and a slight reaction–defined as a slight flinch, slight shake, short acceleration, or immediate dive–when hit (54%). Severe immediate reactions were never observed. Hit or miss and age-sex class were important predictors of the reaction, but the method (tag or biopsy) was unimportant. Multievent trap-dependence modelling revealed considerable variation in individual sighting patterns; however, there were no significant mid- or long-term changes following biopsy sampling or tagging.
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Affiliation(s)
- Ryan R. Reisinger
- Mammal Research Institute, Department of Zoology and Entomology, University of Pretoria, Pretoria, South Africa
- * E-mail:
| | - W. Chris Oosthuizen
- Mammal Research Institute, Department of Zoology and Entomology, University of Pretoria, Pretoria, South Africa
| | - Guillaume Péron
- Centre for Statistics in Ecology, Environment and Conservation, Department of Statistical Sciences, University of Cape Town, Cape Town, South Africa
| | - Dawn Cory Toussaint
- Mammal Research Institute, Department of Zoology and Entomology, University of Pretoria, Pretoria, South Africa
| | - Russel D. Andrews
- School of Fisheries and Ocean Sciences, University of Alaska Fairbanks, Fairbanks, Alaska, United States of America
- Alaska SeaLife Center, Seward, Alaska, United States of America
| | - P. J. Nico de Bruyn
- Mammal Research Institute, Department of Zoology and Entomology, University of Pretoria, Pretoria, South Africa
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87
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Complexity in animal behaviour: towards common ground. Acta Ethol 2014. [DOI: 10.1007/s10211-014-0205-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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88
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Butti C, Janeway CM, Townshend C, Wicinski BA, Reidenberg JS, Ridgway SH, Sherwood CC, Hof PR, Jacobs B. The neocortex of cetartiodactyls: I. A comparative Golgi analysis of neuronal morphology in the bottlenose dolphin (Tursiops truncatus), the minke whale (Balaenoptera acutorostrata), and the humpback whale (Megaptera novaeangliae). Brain Struct Funct 2014; 220:3339-68. [PMID: 25100560 DOI: 10.1007/s00429-014-0860-3] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2014] [Accepted: 07/25/2014] [Indexed: 12/12/2022]
Abstract
The present study documents the morphology of neurons in several regions of the neocortex from the bottlenose dolphin (Tursiops truncatus), the North Atlantic minke whale (Balaenoptera acutorostrata), and the humpback whale (Megaptera novaeangliae). Golgi-stained neurons (n = 210) were analyzed in the frontal and temporal neocortex as well as in the primary visual and primary motor areas. Qualitatively, all three species exhibited a diversity of neuronal morphologies, with spiny neurons including typical pyramidal types, similar to those observed in primates and rodents, as well as other spiny neuron types that had more variable morphology and/or orientation. Five neuron types, with a vertical apical dendrite, approximated the general pyramidal neuron morphology (i.e., typical pyramidal, extraverted, magnopyramidal, multiapical, and bitufted neurons), with a predominance of typical and extraverted pyramidal neurons. In what may represent a cetacean morphological apomorphy, both typical pyramidal and magnopyramidal neurons frequently exhibited a tri-tufted variant. In the humpback whale, there were also large, star-like neurons with no discernable apical dendrite. Aspiny bipolar and multipolar interneurons were morphologically consistent with those reported previously in other mammals. Quantitative analyses showed that neuronal size and dendritic extent increased in association with body size and brain mass (bottlenose dolphin < minke whale < humpback whale). The present data thus suggest that certain spiny neuron morphologies may be apomorphies in the neocortex of cetaceans as compared to other mammals and that neuronal dendritic extent covaries with brain and body size.
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Affiliation(s)
- Camilla Butti
- Fishberg Department of Neuroscience and Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, Box 1639, One Gustave L. Levy Place, New York, NY, 10029, USA.
| | - Caroline M Janeway
- Laboratory of Quantitative Neuromorphology, Psychology, Colorado College, 14 E. Cache La Poudre, Colorado Springs, CO, 80903, USA
| | - Courtney Townshend
- Laboratory of Quantitative Neuromorphology, Psychology, Colorado College, 14 E. Cache La Poudre, Colorado Springs, CO, 80903, USA
| | - Bridget A Wicinski
- Fishberg Department of Neuroscience and Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, Box 1639, One Gustave L. Levy Place, New York, NY, 10029, USA
| | - Joy S Reidenberg
- Center for Anatomy and Functional Morphology, Icahn School of Medicine at Mount Sinai, One Gustave L. Levy Place, New York, NY, 10029, USA
| | - Sam H Ridgway
- National Marine Mammal Foundation, 2240 Shelter Island Drive, San Diego, CA, 92106, USA
| | - Chet C Sherwood
- Department of Anthropology, The George Washington University, 2110 G Street NW, Washington, DC, 20052, USA
| | - Patrick R Hof
- Fishberg Department of Neuroscience and Friedman Brain Institute, Icahn School of Medicine at Mount Sinai, Box 1639, One Gustave L. Levy Place, New York, NY, 10029, USA
| | - Bob Jacobs
- Laboratory of Quantitative Neuromorphology, Psychology, Colorado College, 14 E. Cache La Poudre, Colorado Springs, CO, 80903, USA
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89
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Budka M, Osiejuk TS. Individually specific call feature is not used to neighbour-stranger discrimination: the corncrake case. PLoS One 2014; 9:e104031. [PMID: 25090457 PMCID: PMC4121243 DOI: 10.1371/journal.pone.0104031] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2014] [Accepted: 07/09/2014] [Indexed: 11/18/2022] Open
Abstract
In various contexts, animals rely on acoustic signals to differentiate between conspecifics. Currently, studies examining vocal signatures use two main approaches. In the first approach, researchers search for acoustic characteristics that have the potential to be individual specific. This approach yields information on variation in signal parameters both within and between individuals and generates practical tools that can be used in population monitoring. In the second approach, playback experiments with natural calls are conducted to discern whether animals are capable of discriminating among the vocal signatures of different individuals. However, both approaches do not reveal the exact signal characteristics that are being used in the discrimination process. In this study, we tested whether an individual-specific call characteristic – namely the length of the intervals between successive maximal amplitude peaks within syllables (PPD) – is crucial in neighbour-stranger discrimination by males of the nocturnal and highly secretive bird species, the corncrake (Crex crex). We conducted paired playback experiments in which corncrakes (n = 47) were exposed to artificial calls with PPD characteristics of neighbour and stranger birds. These artificial calls differed only in PPD structure. The calls were broadcast from a speaker, and we recorded the birds' behavioural responses. Although corncrakes have previously been experimentally shown to discriminate between neighbours and strangers, we found no difference in the responses to the artificial calls representing neighbours versus strangers. This finding demonstrates that even if vocal signatures are individual specific within a species, it does not automatically mean that said signatures are being crucial in discrimination among individuals. At the same time, the birds' aggressive responses to the artificial calls indicated that the information transmitted by PPDs is important in species-specific call recognition and may be used by males and/or females to evaluate sender quality, similarly like sound frequency in some insect species.
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Affiliation(s)
- Michał Budka
- Department of Behavioural Ecology, Institute of Environmental Biology, Faculty of Biology, Adam Mickiewicz University, Poznań, Poland
- * E-mail:
| | - Tomasz S. Osiejuk
- Department of Behavioural Ecology, Institute of Environmental Biology, Faculty of Biology, Adam Mickiewicz University, Poznań, Poland
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90
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Johnson CM, Sullivan J, Buck CL, Trexel J, Scarpuzzi M. Visible and invisible displacement with dynamic visual occlusion in bottlenose dolphins (Tursiops spp). Anim Cogn 2014; 18:179-93. [PMID: 25092491 DOI: 10.1007/s10071-014-0788-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2014] [Revised: 06/14/2014] [Accepted: 07/15/2014] [Indexed: 02/03/2023]
Abstract
Anticipating the location of a temporarily obscured target-what Piaget (the construction of reality in the child. Basic Books, New York, 1954) called "object permanence"-is a critical skill, especially in hunters of mobile prey. Previous research with bottlenose dolphins found they could predict the location of a target that had been visibly displaced into an opaque container, but not one that was first placed in an opaque container and then invisibly displaced to another container. We tested whether, by altering the task to involve occlusion rather than containment, these animals could show more advanced object permanence skills. We projected dynamic visual displays at an underwater-viewing window and videotaped the animals' head moves while observing these displays. In Experiment 1, the animals observed a small black disk moving behind occluders that shifted in size, ultimately forming one large occluder. Nine out of ten subjects "tracked" the presumed movement of the disk behind this occluder on their first trial-and in a statistically significant number of subsequent trials-confirming their visible displacement abilities. In Experiment 2, we tested their invisible displacement abilities. The disk first disappeared behind a pair of moving occluders, which then moved behind a stationary occluder. The moving occluders then reappeared and separated, revealing that the disk was no longer behind them. The subjects subsequently looked to the correct stationary occluder on eight of their ten first trials, and in a statistically significant number of subsequent trials. Thus, by altering the stimuli to be more ecologically valid, we were able to show that the dolphins could indeed succeed at an invisible displacement task.
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91
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Kelley TC, Higdon JW, Ferguson SH. Large testes and brain sizes in odontocetes (order Cetacea, suborder Odontoceti): the influence of mating system on encephalization. CAN J ZOOL 2014. [DOI: 10.1139/cjz-2014-0044] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Little is known about their mating systems, but odontocetes may utilize the same types of mating systems as terrestrial mammals. Species with relatively large testes are likely to be polygynandrous, while species with smaller testes and greater sexual size dimorphism (SSD) are predicted to be polygynous. The “Machiavellian intelligence or sexual conflict” hypothesis predicts that polygynadrous species also evolved larger brains both to coerce conspecifics to mate and to resist mating attempts by undesirable mates. The “costly tissue” hypothesis predicts that species investing heavily in testes invest less in brain tissue and vice versa to conserve energy. Residual testes and brain mass measurements were used to test the sexual conflict and costly tissue hypotheses in 40 species of odontocetes. Correlations were performed on both raw data and independent contrasts to control for phylogeny. There was a significant positive correlation between residual testes mass and SSD in both data sets, and between residual testes mass and residual brain mass in the non-phylogenetically controlled data set. Results indicate a negative relationship between increased testes masses and SSD in odontocetes. There was no support for the costly tissue hypothesis. Support for Machiavellian intelligence or sexual conflict hypothesis was found only when phylogenetic effects were not considered.
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Affiliation(s)
- Trish C. Kelley
- Department of Environment and Geography, University of Manitoba, Winnipeg, MB R3T 2N2, Canada
| | - Jeff W. Higdon
- Higdon Wildlife Consulting, 912 Ashburn Street, Winnipeg, MB R3G 3C9, Canada
| | - Steven H. Ferguson
- Fisheries and Oceans Canada, 501 University Crescent, Winnipeg, MB R3T 2N6, Canada
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92
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The neocortex of cetartiodactyls. II. Neuronal morphology of the visual and motor cortices in the giraffe (Giraffa camelopardalis). Brain Struct Funct 2014; 220:2851-72. [PMID: 25048683 DOI: 10.1007/s00429-014-0830-9] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2014] [Accepted: 06/21/2014] [Indexed: 12/24/2022]
Abstract
The present quantitative study extends our investigation of cetartiodactyls by exploring the neuronal morphology in the giraffe (Giraffa camelopardalis) neocortex. Here, we investigate giraffe primary visual and motor cortices from perfusion-fixed brains of three subadults stained with a modified rapid Golgi technique. Neurons (n = 244) were quantified on a computer-assisted microscopy system. Qualitatively, the giraffe neocortex contained an array of complex spiny neurons that included both "typical" pyramidal neuron morphology and "atypical" spiny neurons in terms of morphology and/or orientation. In general, the neocortex exhibited a vertical columnar organization of apical dendrites. Although there was no significant quantitative difference in dendritic complexity for pyramidal neurons between primary visual (n = 78) and motor cortices (n = 65), there was a significant difference in dendritic spine density (motor cortex > visual cortex). The morphology of aspiny neurons in giraffes appeared to be similar to that of other eutherian mammals. For cross-species comparison of neuron morphology, giraffe pyramidal neurons were compared to those quantified with the same methodology in African elephants and some cetaceans (e.g., bottlenose dolphin, minke whale, humpback whale). Across species, the giraffe (and cetaceans) exhibited less widely bifurcating apical dendrites compared to elephants. Quantitative dendritic measures revealed that the elephant and humpback whale had more extensive dendrites than giraffes, whereas the minke whale and bottlenose dolphin had less extensive dendritic arbors. Spine measures were highest in the giraffe, perhaps due to the high quality, perfusion fixation. The neuronal morphology in giraffe neocortex is thus generally consistent with what is known about other cetartiodactyls.
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93
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94
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Butterworth A, Brakes P, Vail CS, Reiss D. A veterinary and behavioral analysis of dolphin killing methods currently used in the "drive hunt" in Taiji, Japan. J APPL ANIM WELF SCI 2013; 16:184-204. [PMID: 23544757 DOI: 10.1080/10888705.2013.768925] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Annually in Japanese waters, small cetaceans are killed in "drive hunts" with quotas set by the government of Japan. The Taiji Fishing Cooperative in Japan has published the details of a new killing method that involves cutting (transecting) the spinal cord and purports to reduce time to death. The method involves the repeated insertion of a metal rod followed by the plugging of the wound to prevent blood loss into the water. To date, a paucity of data exists regarding these methods utilized in the drive hunts. Our veterinary and behavioral analysis of video documentation of this method indicates that it does not immediately lead to death and that the time to death data provided in the description of the method, based on termination of breathing and movement, is not supported by the available video data. The method employed causes damage to the vertebral blood vessels and the vascular rete from insertion of the rod that will lead to significant hemorrhage, but this alone would not produce a rapid death in a large mammal of this type. The method induces paraplegia (paralysis of the body) and death through trauma and gradual blood loss. This killing method does not conform to the recognized requirement for "immediate insensibility" and would not be tolerated or permitted in any regulated slaughterhouse process in the developed world.
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Affiliation(s)
- Andrew Butterworth
- Clinical Veterinary School, University of Bristol Veterinary School, Langford, United Kingdom
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95
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Manger P. Questioning the interpretations of behavioral observations of cetaceans: Is there really support for a special intellectual status for this mammalian order? Neuroscience 2013; 250:664-96. [DOI: 10.1016/j.neuroscience.2013.07.041] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2013] [Accepted: 07/17/2013] [Indexed: 11/26/2022]
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96
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Montgomery SH, Geisler JH, McGowen MR, Fox C, Marino L, Gatesy J. The evolutionary history of cetacean brain and body size. Evolution 2013; 67:3339-53. [PMID: 24152011 DOI: 10.1111/evo.12197] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2013] [Accepted: 06/13/2013] [Indexed: 11/30/2022]
Abstract
Cetaceans rival primates in brain size relative to body size and include species with the largest brains and biggest bodies to have ever evolved. Cetaceans are remarkably diverse, varying in both phenotypes by several orders of magnitude, with notable differences between the two extant suborders, Mysticeti and Odontoceti. We analyzed the evolutionary history of brain and body mass, and relative brain size measured by the encephalization quotient (EQ), using a data set of extinct and extant taxa to capture temporal variation in the mode and direction of evolution. Our results suggest that cetacean brain and body mass evolved under strong directional trends to increase through time, but decreases in EQ were widespread. Mysticetes have significantly lower EQs than odontocetes due to a shift in brain:body allometry following the divergence of the suborders, caused by rapid increases in body mass in Mysticeti and a period of body mass reduction in Odontoceti. The pattern in Cetacea contrasts with that in primates, which experienced strong trends to increase brain mass and relative brain size, but not body mass. We discuss what these analyses reveal about the convergent evolution of large brains, and highlight that until recently the most encephalized mammals were odontocetes, not primates.
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Affiliation(s)
- Stephen H Montgomery
- Department of Zoology, University of Cambridge, Downing Street, Cambridge, United Kingdom.
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97
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Janik VM, Sayigh LS. Communication in bottlenose dolphins: 50 years of signature whistle research. J Comp Physiol A Neuroethol Sens Neural Behav Physiol 2013; 199:479-89. [DOI: 10.1007/s00359-013-0817-7] [Citation(s) in RCA: 147] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2012] [Revised: 04/02/2013] [Accepted: 04/04/2013] [Indexed: 11/29/2022]
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98
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Racicot RA, Colbert MW. Morphology and Variation in Porpoise (Cetacea: Phocoenidae) Cranial Endocasts. Anat Rec (Hoboken) 2013; 296:979-92. [DOI: 10.1002/ar.22704] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2012] [Accepted: 03/20/2013] [Indexed: 11/09/2022]
Affiliation(s)
- Rachel A. Racicot
- Department of Geology and Geophysics; Yale University; New Haven Connecticut
| | - Matthew W. Colbert
- Jackson School of Geosciences; The University of Texas at Austin; Austin Texas
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99
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Chinea A, Korutcheva E. Intelligence and embodiment: A statistical mechanics approach. Neural Netw 2013; 40:52-72. [DOI: 10.1016/j.neunet.2013.01.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2012] [Revised: 01/11/2013] [Accepted: 01/11/2013] [Indexed: 10/27/2022]
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100
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Zilles K, Palomero-Gallagher N, Amunts K. Development of cortical folding during evolution and ontogeny. Trends Neurosci 2013; 36:275-84. [PMID: 23415112 DOI: 10.1016/j.tins.2013.01.006] [Citation(s) in RCA: 357] [Impact Index Per Article: 32.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2012] [Revised: 01/14/2013] [Accepted: 01/22/2013] [Indexed: 12/23/2022]
Abstract
Cortical folding is a hallmark of many, but not all, mammalian brains. The degree of folding increases with brain size across mammals, but at different scales between orders and families. In this review we summarize recent studies that have shed light on cortical folding and discuss new models that arise from these data. Genetic analyses argue for an independent development of brain volume and gyrification, but more recent data on the cellular development of the cortex and its connectivity highlight the role of these processes in cortical folding (grey matter hypothesis). This, and the widely discussed tension hypothesis, further tested by analyzing the mechanical properties of maturing nerve fibers, synapses, and dendrites, can provide the basis for a future integrative view on cortical folding.
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Affiliation(s)
- Karl Zilles
- Research Centre Juelich, Institute for Neuroscience and Medicine (INM-1), Juelich, Germany.
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