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Chidambaram S, Wintergerst S, Kacelnik A, Nachev V, Winter Y. Serial reversal learning in nectar-feeding bats. Anim Cogn 2024; 27:24. [PMID: 38451365 PMCID: PMC10920430 DOI: 10.1007/s10071-024-01836-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2023] [Revised: 01/05/2024] [Accepted: 01/09/2024] [Indexed: 03/08/2024]
Abstract
We explored the behavioral flexibility of Commissaris's long-tongued bats through a spatial serial reversal foraging task. Bats kept in captivity for short periods were trained to obtain nectar rewards from two artificial flowers. At any given time, only one of the flowers provided rewards and these reward contingencies reversed in successive blocks of 50 flower visits. All bats detected and responded to reversals by making most of their visits to the currently active flower. As the bats experienced repeated reversals, their preference re-adjusted faster. Although the flower state reversals were theoretically predictable, we did not detect anticipatory behavior, that is, frequency of visits to the alternative flower did not increase within each block as the programmed reversal approached. The net balance of these changes was a progressive improvement in performance in terms of the total proportion of visits allocated to the active flower. The results are compatible with, but do not depend on, the bats displaying an ability to 'learn to learn' and show that the dynamics of allocation of effort between food sources can change flexibly according to circumstances.
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Affiliation(s)
- Shambhavi Chidambaram
- Institute of Biology, Humboldt University, Philippstraße 13, 10115, Berlin, Germany
- Berlin School of Mind and Brain, Humboldt University, Berlin, Germany
| | | | - Alex Kacelnik
- Department of Biology and Pembroke College, University of Oxford, Oxford, UK
| | - Vladislav Nachev
- Institute of Biology, Humboldt University, Philippstraße 13, 10115, Berlin, Germany
- QUEST Center for Responsible Research, Berlin Institute of Health at Charité-Universitätsmedizin, Charitéplatz 1, 10117, Berlin, Germany
| | - York Winter
- Institute of Biology, Humboldt University, Philippstraße 13, 10115, Berlin, Germany.
- Berlin School of Mind and Brain, Humboldt University, Berlin, Germany.
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2
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Rose A, Tschapka M, Knörnschild M. Social information facilitates learning about novel food sources in adult flower-visiting bats. Anim Cogn 2023; 26:1635-1642. [PMID: 37421496 PMCID: PMC10442281 DOI: 10.1007/s10071-023-01807-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2023] [Revised: 05/22/2023] [Accepted: 06/28/2023] [Indexed: 07/10/2023]
Abstract
Incorporating novel food sources into their diet is crucial for animals in changing environments. Although the utilization of novel food sources can be learned individually, learning socially from experienced conspecifics may facilitate this task and enable a transmission of foraging-related innovations across a population. In anthropogenically modified habitats, bats (Mammalia: Chiroptera) frequently adapt their feeding strategy to novel food sources, and corresponding social learning processes have been experimentally demonstrated in frugivorous and animalivorous species. However, comparable experiments are lacking for nectarivorous flower-visiting bats, even though their utilization of novel food sources in anthropogenically altered habitats is often observed and even discussed as the reason why bats are able to live in some areas. In the present study, we investigated whether adult flower-visiting bats may benefit from social information when learning about a novel food source. We conducted a demonstrator-observer dyad with wild Pallas' long-tongued bats (Glossophaga soricina; Phyllostomidae: Glossophaginae) and hypothesized that naïve individuals would learn to exploit a novel food source faster when accompanied by an experienced demonstrator bat. Our results support this hypothesis and demonstrate flower-visiting bats to be capable of using social information to expand their dietary repertoire.
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Affiliation(s)
- Andreas Rose
- Institute of Evolutionary Ecology and Conservation Genomics, University of Ulm, Albert-Einstein-Allee 11, 89069, Ulm, Germany.
| | - Marco Tschapka
- Institute of Evolutionary Ecology and Conservation Genomics, University of Ulm, Albert-Einstein-Allee 11, 89069, Ulm, Germany
- Smithsonian Tropical Research Institute, Building 401 Tupper, Luis Clement Avenue, Balboa Ancon, Panama, Republic of Panama
| | - Mirjam Knörnschild
- Smithsonian Tropical Research Institute, Building 401 Tupper, Luis Clement Avenue, Balboa Ancon, Panama, Republic of Panama
- Museum für Naturkunde-Leibniz Institute for Evolution and Biodiversity Science, Invalidenstraße 43, 10115, Berlin, Germany
- Institute for Biology, Humboldt-Universität Zu Berlin, Invalidenstr. 42, 10115, Berlin, Germany
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3
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Kobayashi K, Hotta T, Sakai O, Mori A. Investigation of mechanisms underlying a light approaching behavior in a house gecko by comparative and learning experiments. Behav Processes 2023; 205:104806. [PMID: 36574892 DOI: 10.1016/j.beproc.2022.104806] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Revised: 11/09/2022] [Accepted: 12/23/2022] [Indexed: 12/26/2022]
Abstract
Nocturnal predators of many taxa are known to come to artificial light at night for foraging on clumped food resources. Both innate and acquired light preferences seem to be possible mechanisms of light approaching behavior although empirical tests are lacking in most nocturnal predators. Here, using a Japanese gecko Gekko japonicus, we investigated whether geckos have a light preference and how foraging experiences under the light reinforce light approaching tendency. In a comparative experiment, there was no difference in light approaching behavior between urban and suburban geckos irrespective of their original light habitats. In an associative learning experiment, geckos did not significantly change light approaching behavior even after repeated opportunities to forage crickets near a lamp in the laboratory setting. These results imply that light approaching behavior of Japanese geckos may not be easily reinforced by foraging experiences under the light. Although we often witness geckos coming to artificial light at night, our findings may not suggest their light preference. Geckos may approach the light-up foraging spot based on other cues relating to the artificial light environment.
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Affiliation(s)
- Kohei Kobayashi
- Department of Zoology, Graduate School of Science, Kyoto University, Sakyo, Kyoto, Japan.
| | - Takashi Hotta
- Department of Psychology, Graduate School of Letters, Kyoto University, Sakyo, Kyoto, Japan
| | - Osamu Sakai
- Department of Zoology, Graduate School of Science, Kyoto University, Sakyo, Kyoto, Japan; Department of Environmental Science and Policy, University of California Davis, CA, US
| | - Akira Mori
- Department of Zoology, Graduate School of Science, Kyoto University, Sakyo, Kyoto, Japan
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4
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A bibliometric analysis of research trends in bat echolocation studies between 1970 and 2021. ECOL INFORM 2022. [DOI: 10.1016/j.ecoinf.2022.101654] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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5
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Hemingway CT, Aversa III JC, Ryan MJ, Page RA. Context-dependent preferences in wild fruit bats. Anim Behav 2021. [DOI: 10.1016/j.anbehav.2021.06.016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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6
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Constitutive Neurogenesis in the Brain of Different Vertebrate Groups. NEUROPHYSIOLOGY+ 2021. [DOI: 10.1007/s11062-021-09904-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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7
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Jacomassa FAF, Bernardi IP, Passos FDEC. Seasonal diet variation, preferences and availability of resources consumed by Sturnira lilium (É. Geoffroy St.-Hilaire, 1810) (Chiroptera: Phyllostomidae) in Brazilian seasonal deciduous forest. AN ACAD BRAS CIENC 2021; 93:e20201571. [PMID: 34076185 DOI: 10.1590/0001-3765202120201571] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2020] [Accepted: 02/27/2021] [Indexed: 11/22/2022] Open
Abstract
Sturnira lilium is a frugivorous bat that is known for its high consumption of Solanaceae fruits. We captured S. lilium, using mistnets, to study its diet and diet seasonal variation in a seasonal deciduous forest in southern Brazil. We also investigated the predominance of Solanaceae and of Solanum granulosoleprosum, the main food source, correlated with the availability of ripe fruits. A total of 11 plant species were identified from 126 fecal samples. Seeds of Solanaceae species were present in 81% of the samples, with S. granulosoleprosum seeds being the most common (68.3 %). There was no seasonal variation in the diet; however ANOVA revealed that the consumption of Solanaceae and S. granulosoleprosum showed monthly differences. There was no monthly correlation and there was a weak seasonal correlation between ripe fruit availability and the consumption of S. granulosoleprosum by S. lilium, indicating that this bat species occupies broad home ranges and is capable of locating plants with mature fruits in adjacent areas during most of the year. The mobility of S. lilium and high abundance of S. granulosoleprosum in the diet suggests that this species as good disperser of plants that are characteristic of early successional stages and areas undergoing regeneration.
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Affiliation(s)
- Fábio A F Jacomassa
- Universidade Regional Integrada do Alto Uruguai e das Missões, Departamento de Ciências Biológicas, Campus de Frederico Westphalen, Avenida Assis Brasil, 709, Itapajé, 99400-000 Frederico Westphalen, RS, Brazil
| | - Itiberê P Bernardi
- Pontifícia Universidade Católica do Paraná, Escola de Ciências da Vida, Curso de Ciências Biológicas, Rua Imaculada Conceição, 1155, Prado Velho, 80215-901 Curitiba, PR, Brazil.,Universidade Federal do Paraná, Departamento de Zoologia, Laboratório de Biodiversidade, Conservação e Ecologia de Animais Silvestres, Jardim das Américas, 81531-980 Curitiba, PR, Brazil
| | - Fernando DE C Passos
- Universidade Federal do Paraná, Departamento de Zoologia, Laboratório de Biodiversidade, Conservação e Ecologia de Animais Silvestres, Jardim das Américas, 81531-980 Curitiba, PR, Brazil
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8
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Brokaw AF, Smotherman M. Olfactory tracking strategies in a neotropical fruit bat. J Exp Biol 2021; 224:jeb231829. [PMID: 33536298 PMCID: PMC7904095 DOI: 10.1242/jeb.231829] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2020] [Accepted: 01/11/2021] [Indexed: 11/20/2022]
Abstract
Many studies have characterized olfactory-tracking behaviors in animals, and it has been proposed that search strategies may be generalizable across a wide range of species. Olfaction is important for fruit- and nectar-feeding bats, but it is uncertain whether existing olfactory search models can predict the strategies of flying mammals that emit echolocation pulses through their nose. Quantitative assessments of how well echolocating bats track and localize odor sources are lacking, so we developed a behavioral assay to characterize the olfactory detection and tracking behavior of crawling northern yellow-shouldered bats (Sturnira parvidens), a common neotropical frugivore. Trained bats were presented with a choice between control and banana-odor-infused solutions in a series of experiments that confirmed that bats are able to locate a reward based on odor cues alone and examined the effect of odor concentration on olfactory search behaviors. Decision distance (the distance from which bats made their change in direction before directly approaching the target) was distinctly bimodal, with an observed peak that coincided with an inflection point in the odor concentration gradient. We observed two main search patterns that are consistent with both serial sampling and learned route-following strategies. These results support the hypothesis that bats can combine klinotaxis with spatial awareness of experimental conditions to locate odor sources, similar to terrestrial mammals. Contrary to existing models, bats did not display prominent head-scanning behaviors during their final approach, which may be due to constraints of nasal-emitted biosonar for orientation.
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Affiliation(s)
- Alyson F Brokaw
- Interdisciplinary Program in Ecology and Evolutionary Biology, Texas A&M University, College Station, TX, USA
- Department of Biology, Texas A&M University, College Station, TX, USA
| | - Michael Smotherman
- Interdisciplinary Program in Ecology and Evolutionary Biology, Texas A&M University, College Station, TX, USA
- Department of Biology, Texas A&M University, College Station, TX, USA
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9
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Lewanzik D, Goerlitz HR. Task-dependent vocal adjustments to optimize biosonar-based information acquisition. J Exp Biol 2021; 224:jeb234815. [PMID: 33234681 DOI: 10.1242/jeb.234815] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2020] [Accepted: 11/13/2020] [Indexed: 01/09/2023]
Abstract
Animals need to acquire adequate and sufficient information to guide movements, yet information acquisition and processing are costly. Animals thus face a trade-off between gathering too little and too much information and, accordingly, actively adapt sensory input through motor control. Echolocating animals provide a unique opportunity to study the dynamics of adaptive sensing in naturally behaving animals, as every change in the outgoing echolocation signal directly affects information acquisition and the perception of the dynamic acoustic scene. Here, we investigated the flexibility with which bats dynamically adapt information acquisition depending on a task. We recorded the echolocation signals of wild-caught Western barbastelle bats (Barbastella barbastellus) while they were flying through an opening, drinking on the wing, landing on a wall and capturing prey. We show that the echolocation signal sequences during target approach differed in a task-dependent manner; bats started the target approach earlier and increased the information update rate more when the task became increasingly difficult, and bats also adjusted the dynamics of call duration shortening and peak frequency shifts accordingly. These task-specific differences existed from the onset of object approach, implying that bats plan their sensory-motor programme for object approach exclusively based on information received from search call echoes. We provide insight into how echolocating animals deal with the constraints they face when sequentially sampling the world through sound by adjusting acoustic information flow from slow to extremely fast in a highly dynamic manner. Our results further highlight the paramount importance of high behavioural flexibility for acquiring information.
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Affiliation(s)
- Daniel Lewanzik
- Acoustic and Functional Ecology, Max Planck Institute for Ornithology, Eberhard-Gwinner-Straße, 82319 Seewiesen, Germany
| | - Holger R Goerlitz
- Acoustic and Functional Ecology, Max Planck Institute for Ornithology, Eberhard-Gwinner-Straße, 82319 Seewiesen, Germany
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10
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Knörnschild M, Fernandez AA. Do Bats Have the Necessary Prerequisites for Symbolic Communication? Front Psychol 2020; 11:571678. [PMID: 33262725 PMCID: PMC7688458 DOI: 10.3389/fpsyg.2020.571678] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2020] [Accepted: 10/12/2020] [Indexed: 11/20/2022] Open
Abstract
Training animals such as apes, gray parrots, or dolphins that communicate via arbitrary symbols with humans has revealed astonishing mental capacities that may have otherwise gone unnoticed. Albeit bats have not yet been trained to communicate via symbols with humans, we are convinced that some species, especially captive Pteropodid bats ("flying foxes"), show the potential to master this cognitive task. Here, we briefly review what is known about bats' cognitive skills that constitute relevant prerequisites for symbolic communication with humans. We focus on social learning in general, trainability by humans, associative learning from humans, imitation, vocal production learning and usage learning, and social knowledge. Moreover, we highlight potential training paradigms that could be used to elicit simple "symbolic" bat-human communication, i.e., training bats to select arbitrary symbols on a touchscreen to elicit a desired behavior of the human caregiver. Touchscreen-proficient bats could participate in cognition research, e.g., to study their numerical competence or categorical perception, to further elucidate how nonhuman animals learn and perceive the world.
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Affiliation(s)
- Mirjam Knörnschild
- Museum für Naturkunde, Leibniz-Institute for Evolution and Biodiversity Science, Berlin, Germany
- Animal Behavior Lab, Freie Universität, Berlin, Germany
- Smithsonian Tropical Research Institute, Ancón, Panama
| | - Ahana A. Fernandez
- Museum für Naturkunde, Leibniz-Institute for Evolution and Biodiversity Science, Berlin, Germany
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11
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Rose A, Tschapka M, Knörnschild M. Visits at artificial RFID flowers demonstrate that juvenile flower-visiting bats perform foraging flights apart from their mothers. Mamm Biol 2020. [DOI: 10.1007/s42991-020-00048-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
AbstractDuring the transition from parental care to independent life, the development of adequate foraging skills is a major challenge for many juvenile mammals. However, participating in their parents’ knowledge by applying social learning strategies might facilitate this task. For several mammals, communal foraging of adults and offspring is suggested to be an important mechanism in mediating foraging-related information. For the large mammalian taxon of bats, only little is known about foraging-related social learning processes during ontogeny. It is often suggested that following their mothers during foraging flights would represent a valuable option for juveniles to socially learn about foraging, e.g., where to find resource-rich foraging patches, but explicit tests are scarce. In the present study, we investigated the foraging behavior of juvenile flower-visiting bats (Glossophaga soricina) in a dry forest in Costa Rica. We tested whether recently volant, but still nursed pups perform foraging flights alone, or whether pups follow their mothers, which would enable pups to socially learn where to feed. For that, we trained mothers and pups to feed from artificial flowers with a RFID reading system and, subsequently, conducted a field experiment to test whether RFID-tagged mothers and pups visit these flowers communally or independently. Unexpectedly, pups often encountered and visited artificial flowers near the day roost, while mothers rarely did, suggesting that they foraged somewhere further away. Our results demonstrate that still nursed juveniles perform foraging flights apart from their mothers and might learn about the spatial distribution of food without participating in their mother’s knowledge, for instance, by following other conspecifics or applying individual learning strategies. An initial potential lack of foraging success in this period is likely compensated by the ongoing maternal provisioning with breast milk and regurgitated nectar during daytime. Our results contribute to the growing body of research on the ontogeny of mammalian foraging behavior in general.
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12
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Hernández-Montero JR, Reusch C, Simon R, Schöner CR, Kerth G. Free-ranging bats combine three different cognitive processes for roost localization. Oecologia 2020; 192:979-988. [PMID: 32236689 PMCID: PMC7165157 DOI: 10.1007/s00442-020-04634-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2019] [Accepted: 03/12/2020] [Indexed: 01/02/2023]
Abstract
Animals have evolved different cognitive processes to localize crucial resources that are difficult to find. Relevant cognitive processes such as associative learning and spatial memory have commonly been studied in a foraging related context under controlled laboratory conditions. However, in natural environments, animals can use multiple cognitive processes to localize resources. In this field study, we used a pairwise choice experiment and automatic roost monitoring to assess how individually marked, free-ranging Bechstein’s bats belonging to two different colonies use associative learning, spatial memory and social information when localizing suitable day roosts. To our knowledge, this study tests for the first time how associative learning, spatial memory and social information are used in the process of roost localization in bats under the natural conditions. We show that, when searching for new roosts, bats used associative learning to discriminate between suitable and unsuitable roosts. For re-localizing previously occupied roosts, bats used spatial memory rather than associative learning. Moreover, bats significantly improved the localization of suitable unfamiliar roosts and tended to increase their accuracy to re-localize previously occupied day roosts using social information. Our field experiments suggest that Bechstein’s bats make hierarchical use of different cognitive processes when localizing day roosts. More generally, our study underlines that evaluating different cues under natural conditions is fundamental to understanding how natural selection has shaped the cognitive processes used for localizing resources.
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Affiliation(s)
- Jesús R Hernández-Montero
- Zoological Institute and Museum, Applied Zoology and Nature Conservation, Greifswald University, Loitzerstraße 26, 17489, Greifswald, Germany.
| | - Christine Reusch
- Zoological Institute and Museum, Applied Zoology and Nature Conservation, Greifswald University, Loitzerstraße 26, 17489, Greifswald, Germany
| | - Ralph Simon
- Department of Ecological Science/Animal Ecology, Faculty of Earth and Life Sciences, Vrije Universiteit Amsterdam, Amsterdam, The Netherlands
| | - Caroline Regina Schöner
- Zoological Institute and Museum, Applied Zoology and Nature Conservation, Greifswald University, Loitzerstraße 26, 17489, Greifswald, Germany
| | - Gerald Kerth
- Zoological Institute and Museum, Applied Zoology and Nature Conservation, Greifswald University, Loitzerstraße 26, 17489, Greifswald, Germany
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13
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Leiser-Miller LB, Kaliszewska ZA, Lauterbur ME, Mann B, Riffell JA, Santana SE. A Fruitful Endeavor: Scent Cues and Echolocation Behavior Used by Carollia castanea to Find Fruit. Integr Org Biol 2020; 2:obaa007. [PMID: 33791551 PMCID: PMC7671165 DOI: 10.1093/iob/obaa007] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Frugivores have evolved sensory and behavioral adaptations that allow them to find ripe fruit effectively, but the relative importance of different senses in varying foraging scenarios is still poorly understood. Within Neotropical ecosystems, short-tailed fruit bats (Carollia: Phyllostomidae) are abundant nocturnal frugivores that rely primarily on Piper fruits as a food resource. Previous research has demonstrated that Carollia employs olfaction and echolocation to locate Piper fruit, but it is unknown how their sensory use and foraging decisions are influenced by the complex diversity of chemical cues that fruiting plants produce. Using free-ranging C. castanea and their preferred food, Piper sancti-felicis, we conducted behavioral experiments to test two main hypotheses: (1) foraging decisions in C. castanea are primarily driven by ripe fruit scent and secondarily by vegetation scent, and (2) C. castanea re-weights their sensory inputs to account for available environmental cues, with bats relying more heavily on echolocation in the absence of adequate scent cues. Our results suggest that C. castanea requires olfactory information and relies almost exclusively on ripe fruit scent to make foraging attempts. Piper sancti-felicis ripe fruit scent is chemically distinct from vegetation scent; it is dominated by 2-heptanol, which is absent from vegetation scent, and has a greater abundance of β-caryophyllene, β-ocimene, γ-elemene, and α-cubebene. Although variation in echolocation call parameters was independent of scent cue presence, bats emitted longer and more frequent echolocation calls in trials where fruit scent was absent. Altogether, these results highlight the adaptations and plasticity of the sensory system in neotropical fruit bats.
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Affiliation(s)
- L B Leiser-Miller
- Department of Biology, University of Washington, Seattle, WA 98195, USA.,Burke Museum of Natural History and Culture, University of Washington, Seattle, WA 98195, USA
| | - Z A Kaliszewska
- Department of Biology, University of Washington, Seattle, WA 98195, USA
| | - M E Lauterbur
- Department of Ecology and Evolutionary Biology, University of Arizona, Tucson, AZ 85721, USA
| | - Brianna Mann
- Department of Biology, University of Washington, Seattle, WA 98195, USA
| | - J A Riffell
- Department of Biology, University of Washington, Seattle, WA 98195, USA
| | - S E Santana
- Department of Biology, University of Washington, Seattle, WA 98195, USA.,Burke Museum of Natural History and Culture, University of Washington, Seattle, WA 98195, USA
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14
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Berrío-Martínez J, Kaiser S, Nowak M, Page RA, Carter GG. The role of past experience in development of feeding behavior in common vampire bats. PeerJ 2019; 7:e7448. [PMID: 31404443 PMCID: PMC6687003 DOI: 10.7717/peerj.7448] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2019] [Accepted: 07/10/2019] [Indexed: 01/18/2023] Open
Abstract
The life history strategy of common vampire bats (Desmodus rotundus) suggests that learning might play a role in development of their foraging skills. We took advantage of 12 captive births in a study colony of vampire bats to test the role of past experience in two aspects of feeding. First, we compared preferences for blood temperature in 32 wild-born vampire bats versus 11 captive-born vampire bats that had only previously fed on blood of ambient temperature or colder. We found no evidence for a preference in either group for blood presented at 4 °C versus 37 °C. Second, we tested whether captive-born vampire bats with no previous experience of feeding on live animals could successfully feed on a live chicken. Five of 12 naïve captive-born bats were able to bite the chicken and draw blood, but only one bat gained more than 5% of body mass. We were unable to reasonably compare their feeding performance with that of wild-born bats because only two of three wild-born, short-term captive bats fed on the chicken and none of the seven wild-born, long-term captive mothers attempted to feed. This unexpected lack of feeding might be due to a previously reported age-dependent neophobia. When six of the captive-born bats were released in the wild, they appeared to feed successfully because they survived for more than three consecutive nights. We suggest further tests that would better clarify the role of learning in the development of foraging in vampire bats.
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Affiliation(s)
| | - Samuel Kaiser
- Smithsonian Tropical Research Institute, Balboa, Ancón, Panama
| | - Michelle Nowak
- Smithsonian Tropical Research Institute, Balboa, Ancón, Panama
| | - Rachel A Page
- Smithsonian Tropical Research Institute, Balboa, Ancón, Panama
| | - Gerald G Carter
- Smithsonian Tropical Research Institute, Balboa, Ancón, Panama.,Department of Evolution, Ecology and Organismal Biology, The Ohio State University, Columbus, OH, United States of America
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15
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Tian L, Zhang B, Zhang J, Zhang T, Cai Y, Qin H, Metzner W, Pan Y. A magnetic compass guides the direction of foraging in a bat. J Comp Physiol A Neuroethol Sens Neural Behav Physiol 2019; 205:619-627. [PMID: 31227860 DOI: 10.1007/s00359-019-01353-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2018] [Revised: 05/22/2019] [Accepted: 06/11/2019] [Indexed: 10/26/2022]
Abstract
Previously, two studies have provided evidence that bats can use magnetic field cues for homing or roosting. For insectivorous bats, it is well established that foraging represents one of the most fundamental behaviors in animals relies on their ability to echolocate. Whether echolocating bats can also use magnetic cues during foraging remains unknown, however. Here, we tested the orientation behavior of Chinese noctules (Nyctalus plancyi) during foraging in a plus-shaped, 4-channel apparatus under different magnetic field conditions. To minimize the effects of spatial memory on orientation from repeated experiments, naïve bats were tested only once in each experimental condition. As expected, under geomagnetic field and a food resource offered conditions, the bats significantly preferred to enter the channel containing food, indicating that they primarily relied on direct sensory signals unrelated to magnetic cues. In contrast, when we offered food simultaneously in all four channels and minimized any differences in all other sensory signals available, the bats exhibited a clear directional preference to forage along the magnetic field direction under either geomagnetic field or a magnetic field in which the horizontal component was rotated by 90°. Our study offers a novel evidence for the importance of a geomagnetic field during foraging.
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Affiliation(s)
- Lanxiang Tian
- Key Laboratory of Earth and Planetary Physics, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing, 100029, China. .,Institutions of Earth Science, Chinese Academy of Sciences, Beijing, 100029, China. .,France-China International Laboratory of Evolution and Development of Magnetotactic Multicellular Organisms, Chinese Academy of Sciences, Beijing, 100029, China. .,University of Chinese Academy of Sciences, Beijing, 100049, China.
| | - Bingfang Zhang
- Key Laboratory of Earth and Planetary Physics, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing, 100029, China.,France-China International Laboratory of Evolution and Development of Magnetotactic Multicellular Organisms, Chinese Academy of Sciences, Beijing, 100029, China.,University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Jinshuo Zhang
- National Zoological Museum, Institute of Zoology, Chinese Academy of Sciences, Beijing, 100101, China
| | - Tongwei Zhang
- Key Laboratory of Earth and Planetary Physics, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing, 100029, China.,Institutions of Earth Science, Chinese Academy of Sciences, Beijing, 100029, China.,France-China International Laboratory of Evolution and Development of Magnetotactic Multicellular Organisms, Chinese Academy of Sciences, Beijing, 100029, China
| | - Yao Cai
- Key Laboratory of Earth and Planetary Physics, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing, 100029, China.,Institutions of Earth Science, Chinese Academy of Sciences, Beijing, 100029, China.,France-China International Laboratory of Evolution and Development of Magnetotactic Multicellular Organisms, Chinese Academy of Sciences, Beijing, 100029, China
| | - Huafeng Qin
- PGL, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing, 100029, China
| | - Walter Metzner
- Department of Integrative Biology and Physiology, University of California Los Angeles, Los Angeles, CA, USA
| | - Yongxin Pan
- Key Laboratory of Earth and Planetary Physics, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing, 100029, China.,Institutions of Earth Science, Chinese Academy of Sciences, Beijing, 100029, China.,France-China International Laboratory of Evolution and Development of Magnetotactic Multicellular Organisms, Chinese Academy of Sciences, Beijing, 100029, China.,University of Chinese Academy of Sciences, Beijing, 100049, China
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16
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Yu C, Luo J, Wohlgemuth M, Moss CF. Echolocating bats inspect and discriminate landmark features to guide navigation. ACTA ACUST UNITED AC 2019; 222:jeb.191965. [PMID: 30936268 DOI: 10.1242/jeb.191965] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2018] [Accepted: 03/26/2019] [Indexed: 11/20/2022]
Abstract
Landmark-guided navigation is a common behavioral strategy for way-finding, yet prior studies have not examined how animals collect sensory information to discriminate landmark features. We investigated this question in animals that rely on active sensing to guide navigation. Four echolocating bats (Eptesicus fuscus) were trained to use an acoustic landmark to find and navigate through a net opening for a food reward. In experimental trials, an object serving as a landmark was placed adjacent to a net opening and an object serving as a distractor was placed next to a barrier (covered opening). The location of the opening, barrier and objects were moved between trials, but the spatial relationships between the landmark and opening, and between the distractor and barrier were maintained. In probe trials, the landmark was placed next to a barrier, while the distractor was placed next to the opening, to test whether the bats relied on the landmark to guide navigation. Vocal and flight behaviors were recorded with an array of ultrasound microphones and high-speed infrared motion-capture cameras. All bats successfully learned to use the landmark to guide navigation through the net opening. Probe trials yielded an increase in both the time to complete the task and the number of net crashes, confirming that the bats relied largely on the landmark to find the net opening. Further, landmark acoustic distinctiveness influenced performance in probe trials and sonar inspection behaviors. Analyses of the animals' vocal behaviors also revealed differences between call features of bats inspecting landmarks compared with distractors, suggesting increased sonar attention to objects used to guide navigation.
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Affiliation(s)
- Chao Yu
- Department of Psychological and Brain Sciences, Johns Hopkins University, 3400 N Charles Street, Baltimore, MD 21218, USA
| | - Jinhong Luo
- Department of Psychological and Brain Sciences, Johns Hopkins University, 3400 N Charles Street, Baltimore, MD 21218, USA
| | - Melville Wohlgemuth
- Department of Psychological and Brain Sciences, Johns Hopkins University, 3400 N Charles Street, Baltimore, MD 21218, USA
| | - Cynthia F Moss
- Department of Psychological and Brain Sciences, Johns Hopkins University, 3400 N Charles Street, Baltimore, MD 21218, USA
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17
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Short-distance pollen dispersal by bats in an urban setting: monitoring the movement of a vertebrate pollinator through fluorescent dyes. Urban Ecosyst 2019. [DOI: 10.1007/s11252-019-0825-7] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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18
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Beck KB, Loretto MC, Ringler M, Hödl W, Pašukonis A. Relying on known or exploring for new? Movement patterns and reproductive resource use in a tadpole-transporting frog. PeerJ 2017; 5:e3745. [PMID: 28875083 PMCID: PMC5580388 DOI: 10.7717/peerj.3745] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2017] [Accepted: 08/07/2017] [Indexed: 11/20/2022] Open
Abstract
Animals relying on uncertain, ephemeral and patchy resources have to regularly update their information about profitable sites. For many tropical amphibians, widespread, scattered breeding pools constitute such fluctuating resources. Among tropical amphibians, poison frogs (Dendrobatidae) exhibit some of the most complex spatial and parental behaviors—including territoriality and tadpole transport from terrestrial clutches to ephemeral aquatic deposition sites. Recent studies have revealed that poison frogs rely on spatial memory to successfully navigate through their environment. This raises the question of when and how these frogs gain information about the area and suitable reproductive resources. To investigate the spatial patterns of pool use and to reveal potential explorative behavior, we used telemetry to follow males of the territorial dendrobatid frog Allobates femoralis during tadpole transport and subsequent homing. To elicit exploration, we reduced resource availability experimentally by simulating desiccated deposition sites. We found that tadpole transport is strongly directed towards known deposition sites and that frogs take similar direct paths when returning to their home territory. Frogs move faster during tadpole transport than when homing after the deposition, which probably reflects different risks and costs during these two movement phases. We found no evidence for exploration, neither during transport nor homing, and independent of the availability of deposition sites. We suggest that prospecting during tadpole transport is too risky for the transported offspring as well as for the transporting male. Relying on spatial memory of multiple previously discovered pools appears to be the predominant and successful strategy for the exploitation of reproductive resources in A. femoralis. Our study provides for the first time a detailed description of poison frog movement patterns during tadpole transport and corroborates recent findings on the significance of spatial memory in poison frogs. When these frogs explore and discover new reproductive resources remains unknown.
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Affiliation(s)
- Kristina B Beck
- Department of Behavioural Ecology and Evolutionary Genetics, Max Planck Institute for Ornithology, Seewiesen, Germany.,Department of Cognitive Biology, University of Vienna, Vienna, Austria
| | | | - Max Ringler
- Department of Ecology and Evolutionary Biology, University of California, Los Angeles, CA, United States of America.,Department of Integrative Zoology, University of Vienna, Vienna, Austria
| | - Walter Hödl
- Department of Integrative Zoology, University of Vienna, Vienna, Austria
| | - Andrius Pašukonis
- Department of Cognitive Biology, University of Vienna, Vienna, Austria.,FAS Center for Systems Biology, Harvard University, Cambridge, MA, United States of America
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19
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Natusch DJD, Lyons JA, Shine R. How do predators and scavengers locate resource hotspots within a tropical forest? AUSTRAL ECOL 2017. [DOI: 10.1111/aec.12492] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Daniel J. D. Natusch
- School of Life and Environmental Sciences University of Sydney Sydney New South Wales 2006 Australia
- Resource Evaluation and Development Frogs Hollow New South Wales Australia
| | - Jessica A. Lyons
- Resource Evaluation and Development Frogs Hollow New South Wales Australia
| | - Richard Shine
- School of Life and Environmental Sciences University of Sydney Sydney New South Wales 2006 Australia
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20
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Ganesh A, Mukilan M, Marimuthu G, Rajan KE. A Novel Food Preference in the Greater Short-Nosed Fruit Bat,Cynopterus sphinx: Mother-Pup Interaction a Strategy for Learning. ACTA CHIROPTEROLOGICA 2016. [DOI: 10.3161/15081109acc2016.18.1.009] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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21
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Pritchard DJ, Hurly TA, Tello-Ramos MC, Healy SD. Why study cognition in the wild (and how to test it)? J Exp Anal Behav 2016; 105:41-55. [DOI: 10.1002/jeab.195] [Citation(s) in RCA: 58] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2015] [Accepted: 12/08/2015] [Indexed: 02/03/2023]
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22
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Pritchard DJ, Scott RD, Healy SD, Hurly AT. Wild rufous hummingbirds use local landmarks to return to rewarded locations. Behav Processes 2015; 122:59-66. [PMID: 26551275 DOI: 10.1016/j.beproc.2015.11.004] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2015] [Revised: 10/31/2015] [Accepted: 11/03/2015] [Indexed: 11/18/2022]
Abstract
Animals may remember an important location with reference to one or more visual landmarks. In the laboratory, birds and mammals often preferentially use landmarks near a goal ("local landmarks") to return to that location at a later date. Although we know very little about how animals in the wild use landmarks to remember locations, mammals in the wild appear to prefer to use distant landmarks to return to rewarded locations. To examine what cues wild birds use when returning to a goal, we trained free-living hummingbirds to search for a reward at a location that was specified by three nearby visual landmarks. Following training we expanded the landmark array to test the extent that the birds relied on the local landmarks to return to the reward. During the test the hummingbirds' search was best explained by the birds having used the experimental landmarks to remember the reward location. How the birds used the landmarks was not clear and seemed to change over the course of each test. These wild hummingbirds, then, can learn locations in reference to nearby visual landmarks.
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Affiliation(s)
| | - Renee D Scott
- Department of Biological Sciences, University of Lethbridge, Alberta, Canada
| | - Susan D Healy
- School of Biology, University of St. Andrews, Fife, UK
| | - Andrew T Hurly
- Department of Biological Sciences, University of Lethbridge, Alberta, Canada
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23
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Rose A, Kolar M, Tschapka M, Knörnschild M. Learning where to feed: the use of social information in flower-visiting Pallas' long-tongued bats (Glossophaga soricina). Anim Cogn 2015; 19:251-62. [PMID: 26497984 DOI: 10.1007/s10071-015-0930-9] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2015] [Revised: 10/07/2015] [Accepted: 10/09/2015] [Indexed: 12/01/2022]
Abstract
Social learning is a widespread phenomenon among vertebrates that influences various patterns of behaviour and is often reported with respect to foraging behaviour. The use of social information by foraging bats was documented in insectivorous, carnivorous and frugivorous species, but there are little data whether flower-visiting nectarivorous bats (Phyllostomidae: Glossophaginae) can acquire information about food from other individuals. In this study, we conducted an experiment with a demonstrator-observer paradigm to investigate whether flower-visiting Pallas' long-tongued bats (Glossophaga soricina) are able to socially learn novel flower positions via observation of, or interaction with, knowledgeable conspecifics. The results demonstrate that flower-visiting G. soricina are able to use social information for the location of novel flower positions and can thereby reduce energy-costly search efforts. This social transmission is explainable as a result of local enhancement; learning bats might rely on both visual and echo-acoustical perception and are likely to eavesdrop on auditory cues that are emitted by feeding conspecifics. We additionally tested the spatial memory capacity of former demonstrator bats when retrieving a learned flower position, and the results indicate that flower-visiting bats remember a learned flower position after several weeks.
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Affiliation(s)
- Andreas Rose
- Institute of Evolutionary Ecology and Conservation Genomics, University of Ulm, Helmholtzstr. 10/1, 89069, Ulm, Germany.
| | - Miriam Kolar
- Institute of Evolutionary Ecology and Conservation Genomics, University of Ulm, Helmholtzstr. 10/1, 89069, Ulm, Germany
| | - Marco Tschapka
- Institute of Evolutionary Ecology and Conservation Genomics, University of Ulm, Helmholtzstr. 10/1, 89069, Ulm, Germany
- Smithsonian Tropical Research Institute, Roosevelt Avenida, Tupper Building 401, Balboa, Panama
| | - Mirjam Knörnschild
- Institute of Evolutionary Ecology and Conservation Genomics, University of Ulm, Helmholtzstr. 10/1, 89069, Ulm, Germany
- Smithsonian Tropical Research Institute, Roosevelt Avenida, Tupper Building 401, Balboa, Panama
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24
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Muchhala N, Serrano D. The Complexity of Background Clutter Affects Nectar Bat Use of Flower Odor and Shape Cues. PLoS One 2015; 10:e0136657. [PMID: 26445216 PMCID: PMC4596802 DOI: 10.1371/journal.pone.0136657] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2015] [Accepted: 08/06/2015] [Indexed: 11/18/2022] Open
Abstract
Given their small size and high metabolism, nectar bats need to be able to quickly locate flowers during foraging bouts. Chiropterophilous plants depend on these bats for their reproduction, thus they also benefit if their flowers can be easily located, and we would expect that floral traits such as odor and shape have evolved to maximize detection by bats. However, relatively little is known about the importance of different floral cues during foraging bouts. In the present study, we undertook a set of flight cage experiments with two species of nectar bats (Anoura caudifer and A. geoffroyi) and artificial flowers to compare the importance of shape and scent cues in locating flowers. In a training phase, a bat was presented an artificial flower with a given shape and scent, whose position was constantly shifted to prevent reliance on spatial memory. In the experimental phase, two flowers were presented, one with the training-flower scent and one with the training-flower shape. For each experimental repetition, we recorded which flower was located first, and then shifted flower positions. Additionally, experiments were repeated in a simple environment, without background clutter, or a complex environment, with a background of leaves and branches. Results demonstrate that bats visit either flower indiscriminately with simple backgrounds, with no significant difference in terms of whether they visit the training-flower odor or training-flower shape first. However, in a complex background olfaction was the most important cue; scented flowers were consistently located first. This suggests that for well-exposed flowers, without obstruction from clutter, vision and/or echolocation are sufficient in locating them. In more complex backgrounds, nectar bats depend more heavily on olfaction during foraging bouts.
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Affiliation(s)
- Nathan Muchhala
- Department of Biology, University of Missouri St. Louis, St. Louis, Missouri, United States of America
- * E-mail:
| | - Diana Serrano
- Escuela de Ciencias Biologicas, Pontificia Universidad Católica del Ecuador, Quito, Ecuador
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25
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Wilson-Rankin EE. Level of experience modulates individual foraging strategies of an invasive predatory wasp. Behav Ecol Sociobiol 2014. [DOI: 10.1007/s00265-014-1861-1] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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26
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Lindsey BW, Di Donato S, Kaslin J, Tropepe V. Sensory-specific modulation of adult neurogenesis in sensory structures is associated with the type of stem cell present in the neurogenic niche of the zebrafish brain. Eur J Neurosci 2014; 40:3591-607. [PMID: 25231569 DOI: 10.1111/ejn.12729] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2014] [Revised: 08/08/2014] [Accepted: 08/20/2014] [Indexed: 01/15/2023]
Abstract
Teleost fishes retain populations of adult stem/progenitor cells within multiple primary sensory processing structures of the mature brain. Though it has commonly been thought that their ability to give rise to adult-born neurons is mainly associated with continuous growth throughout life, whether a relationship exists between the processing function of these structures and the addition of new neurons remains unexplored. We investigated the ultrastructural organisation and modality-specific neurogenic plasticity of niches located in chemosensory (olfactory bulb, vagal lobe) and visual processing (periventricular grey zone, torus longitudinalis) structures of the adult zebrafish (Danio rerio) brain. Transmission electron microscopy showed that the cytoarchitecture of sensory niches includes many of the same cellular morphologies described in forebrain niches. We demonstrate that cells with a radial-glial phenotype are present in chemosensory niches, while the niche of the caudal tectum contains putative neuroepithelial-like cells instead. This was supported by immunohistochemical evidence showing an absence of glial markers, including glial fibrillary acidic protein, glutamine synthetase, and S100β in the tectum. By exposing animals to sensory assays we further illustrate that stem/progenitor cells and their neuronal progeny within sensory structures respond to modality-specific stimulation at distinct stages in the process of adult neurogenesis - chemosensory niches at the level of neuronal survival and visual niches in the size of the stem/progenitor population. Our data suggest that the adult brain has the capacity for sensory-specific modulation of adult neurogenesis and that this property may be associated with the type of stem cell present in the niche.
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Affiliation(s)
- Benjamin W Lindsey
- Australian Regenerative Medicine Institute, Monash University Clayton Campus, Clayton, Vic., Australia
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27
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Hulgard K, Ratcliffe JM. Niche-specific cognitive strategies: object memory interferes with spatial memory in the predatory bat Myotis nattereri. ACTA ACUST UNITED AC 2014; 217:3293-300. [PMID: 25013105 DOI: 10.1242/jeb.103549] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Related species with different diets are predicted to rely on different cognitive strategies: those best suited for locating available and appropriate foods. Here we tested two predictions of the niche-specific cognitive strategies hypothesis in bats, which suggests that predatory species should rely more on object memory than on spatial memory for finding food and that the opposite is true of frugivorous and nectivorous species. Specifically, we predicted that: (1) predatory bats would readily learn to associate shapes with palatable prey and (2) once bats had made such associations, these would interfere with their subsequent learning of a spatial memory task. We trained free-flying Myotis nattereri to approach palatable and unpalatable insect prey suspended below polystyrene objects. Experimentally naïve bats learned to associate different objects with palatable and unpalatable prey but performed no better than chance in a subsequent spatial memory experiment. Because experimental sequence was predicted to be of consequence, we introduced a second group of bats first to the spatial memory experiment. These bats learned to associate prey position with palatability. Control trials indicated that bats made their decisions based on information acquired through echolocation. Previous studies have shown that bat species that eat mainly nectar and fruit rely heavily on spatial memory, reflecting the relative consistency of distribution of fruit and nectar compared with insects. Our results support the niche-specific cognitive strategies hypothesis and suggest that for gleaning and clutter-resistant aerial hawking bats, learning to associate shape with food interferes with subsequent spatial memory learning.
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Affiliation(s)
- Katrine Hulgard
- Sound and Behaviour Group, Department of Biology, University of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark
| | - John M Ratcliffe
- Sound and Behaviour Group, Department of Biology, University of Southern Denmark, Campusvej 55, DK-5230 Odense M, Denmark Department of Ecology and Evolutionary Biology, University of Toronto, 25 Willcocks Street, ON M5S 3B2, Canada Department of Biology, University of Toronto Mississauga, 3359 Mississauga Road, Mississauga, ON L5L 1C6, Canada
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28
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Whitfield M, Köhler A, Nicolson SW. Sunbirds increase foraging success by using color as a cue for nectar quality. Behav Ecol 2013. [DOI: 10.1093/beheco/art115] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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29
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Clare EL, Goerlitz HR, Drapeau VA, Holderied MW, Adams AM, Nagel J, Dumont ER, Hebert PDN, Brock Fenton M. Trophic niche flexibility inGlossophaga soricina: how a nectar seeker sneaks an insect snack. Funct Ecol 2013. [DOI: 10.1111/1365-2435.12192] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
- Elizabeth L. Clare
- School of Biological Sciences University of Bristol Woodland RoadBristol BS8 IUG UK
| | - Holger R. Goerlitz
- School of Biological Sciences University of Bristol Woodland RoadBristol BS8 IUG UK
- Max Planck Institute for Ornithology Sensory Ecology Group Eberhard‐Gwinner‐Straße Seewiesen 82319 Germany
| | - Violaine A. Drapeau
- School of Biological Sciences University of Bristol Woodland RoadBristol BS8 IUG UK
| | - Marc W. Holderied
- School of Biological Sciences University of Bristol Woodland RoadBristol BS8 IUG UK
| | - Amanda M. Adams
- Department of Biology Western University 1151 Richmond StreetLondon ON Canada N6A 5B7
| | - Juliet Nagel
- Center For Environmental Science Appalachian Laboratory University of Maryland 301 Braddock RoadFrostburg MD21532 USA
| | - Elizabeth R. Dumont
- Department of Biology University of Massachusetts 221 Morrill Science Center, 611 N Pleasant St Amherst MA01002 USA
| | - Paul D. N. Hebert
- Department of Integrative Biology Biodiversity Institute of Ontario University of Guelph Guelph ONCanada N1G 2W1
| | - M. Brock Fenton
- Department of Biology Western University 1151 Richmond StreetLondon ON Canada N6A 5B7
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30
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Abstract
We describe an augmented topological map as an alternative for the proposed bicoded map. Inverting causality, the special nature of the vertical dimension is then no longer fixed a priori and the cause of specific navigation behavior, but a consequence of the combination of the specific geometry of the experimental environment and the motor capabilities of the experimental animals.
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31
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32
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Associative memory or algorithmic search: a comparative study on learning strategies of bats and shrews. Anim Cogn 2012; 15:495-504. [DOI: 10.1007/s10071-012-0474-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2011] [Revised: 11/21/2011] [Accepted: 02/08/2012] [Indexed: 10/28/2022]
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33
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Barker JM, Boonstra R, Wojtowicz JM. From pattern to purpose: how comparative studies contribute to understanding the function of adult neurogenesis. Eur J Neurosci 2012; 34:963-77. [PMID: 21929628 DOI: 10.1111/j.1460-9568.2011.07823.x] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
The study of adult neurogenesis has had an explosion of fruitful growth. Yet numerous uncertainties and challenges persist. Our review begins with a survey of species that show evidence of adult neurogenesis. We then discuss how neurogenesis varies across brain regions and point out that regional specializations can indicate functional adaptations. Lifespan and aging are key life-history traits. Whereas 'adult neurogenesis' is the common term in the literature, it does not reflect the reality of neurogenesis being primarily a 'juvenile' phenomenon. We discuss the sharp decline with age as a universal trait of neurogenesis with inevitable functional consequences. Finally, the main body of the review focuses on the function of neurogenesis in birds and mammals. Selected examples illustrate how our understanding of avian and mammalian neurogenesis can complement each other. It is clear that although the two phyla have some common features, the function of adult neurogenesis may not be similar between them and filling the gaps will help us understand neurogenesis as an evolutionarily conserved trait to meet particular ecological pressures.
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Affiliation(s)
- Jennifer M Barker
- GIGA Neurosciences, University of Liège, 1 avenue de l'Hôpital, B-4000 Liège, Belgium.
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34
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How to be a frugivore (in a changing world). ACTA OECOLOGICA-INTERNATIONAL JOURNAL OF ECOLOGY 2011. [DOI: 10.1016/j.actao.2011.01.005] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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35
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Relationship between spatial working memory performance and diet specialization in two sympatric nectar bats. PLoS One 2011; 6:e23773. [PMID: 21931612 PMCID: PMC3170290 DOI: 10.1371/journal.pone.0023773] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2011] [Accepted: 07/25/2011] [Indexed: 11/19/2022] Open
Abstract
Behavioural ecologists increasingly recognise spatial memory as one the most influential cognitive traits involved in evolutionary processes. In particular, spatial working memory (SWM), i.e. the ability of animals to store temporarily useful information for current foraging tasks, determines the foraging efficiency of individuals. As a consequence, SWM also has the potential to influence competitive abilities and to affect patterns of sympatric occurrence among closely related species. The present study aims at comparing the efficiency of SWM between generalist (Glossophaga soricina) and specialist (Leptonycteris yerbabuenae) nectarivorous bats at flowering patches. The two species differ in diet--the generalist diet including seasonally fruits and insects with nectar and pollen while the specialist diet is dominated by nectar and pollen yearlong--and in some morphological traits--the specialist being heavier and with proportionally longer rostrum than the generalist. These bats are found sympatrically within part of their range in the Neotropics. We habituated captive individuals to feed on artificial flower patches and we used infrared video recordings to monitor their ability to remember and avoid the spatial location of flowers they emptied in previous visits in the course of 15-min foraging sequences. Experiments revealed that both species rely on SWM as their foraging success attained significantly greater values than random expectations. However, the nectar specialist L. yerbabuenae was significantly more efficient at extracting nectar (+28% in foraging success), and sustained longer foraging bouts (+27% in length of efficient foraging sequences) than the generalist G. soricina. These contrasting SWM performances are discussed in relation to diet specialization and other life history traits.
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36
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Ganesh A, Bogdanowicz W, Haupt M, Marimuthu G, Rajan KE. Role of olfactory bulb serotonin in olfactory learning in the greater short-nosed fruit bat, Cynopterus sphinx (Chiroptera: Pteropodidae). Brain Res 2010; 1352:108-17. [PMID: 20599808 DOI: 10.1016/j.brainres.2010.06.058] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2010] [Revised: 06/21/2010] [Accepted: 06/23/2010] [Indexed: 10/19/2022]
Abstract
The role of olfactory bulb (OB) serotonin [5-hydroxytryptamine (5-HT)] in olfactory learning and memory was tested in the greater short-nosed fruit bat, Cynopterus sphinx (family Pteropodidae). Graded concentrations (25, 40, and 60microg) of 5,7-dihydroxytryptamine (5,7-DHT) or saline were injected into the OB of bats one day before training to the novel odor. In a behavioral test, 5,7-DHT (60microg) injected bats made significantly fewer feeding attempts and bouts when compared to saline-injected bats during learning and in the memory test. Subsequent biochemical analysis showed that 5-HT level was effectively depleted in the OB of 5,7-DHT injected bats. To test odor-induced 5-HT mediated changes in 5-HT receptors and second messenger cascade in the OB, we examined the expression of 5-HT receptors and mitogen-activated protein kinase (MAPK)/Erk cascade after training to the novel odor. We found that odor stimulation up-regulated the expression of 5-HT(1A) receptor, Erk1 and Creb1 mRNA, and phosphorylation of ERK1 and CREB1. Odor stimulation failed to induce expression in 5-HT-depleted bats, which is similar to control bats and significantly low compared to saline-treated bats. Together these data revealed that the level of 5-HT in the OB may regulate olfactory learning and memory in C. sphinx through Erk and CREB.
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Affiliation(s)
- Ambigapathy Ganesh
- Department of Animal Science, School of Life Sciences, Bharathidasan University, Tiruchirappalli, India
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Flower bats (Glossophaga soricina) and fruit bats (Carollia perspicillata) rely on spatial cues over shapes and scents when relocating food. PLoS One 2010; 5:e10808. [PMID: 20520841 PMCID: PMC2876041 DOI: 10.1371/journal.pone.0010808] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2010] [Accepted: 05/04/2010] [Indexed: 11/19/2022] Open
Abstract
Background Natural selection can shape specific cognitive abilities and the extent to which a given species relies on various cues when learning associations between stimuli and rewards. Because the flower bat Glossophaga soricina feeds primarily on nectar, and the locations of nectar-producing flowers remain constant, G. soricina might be predisposed to learn to associate food with locations. Indeed, G. soricina has been observed to rely far more heavily on spatial cues than on shape cues when relocating food, and to learn poorly when shape alone provides a reliable cue to the presence of food. Methodology/Principal Findings Here we determined whether G. soricina would learn to use scent cues as indicators of the presence of food when such cues were also available. Nectar-producing plants fed upon by G. soricina often produce distinct, intense odors. We therefore expected G. soricina to relocate food sources using scent cues, particularly the flower-produced compound, dimethyl disulfide, which is attractive even to G. soricina with no previous experience of it. We also compared the learning of associations between cues and food sources by G. soricina with that of a related fruit-eating bat, Carollia perspicillata. We found that (1) G. soricina did not learn to associate scent cues, including dimethyl disulfide, with feeding sites when the previously rewarded spatial cues were also available, and (2) both the fruit-eating C. perspicillata and the flower-feeding G. soricina were significantly more reliant on spatial cues than associated sensory cues for relocating food. Conclusions/Significance These findings, taken together with past results, provide evidence of a powerful, experience-independent predilection of both species to rely on spatial cues when attempting to relocate food.
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Influence of Landmarks on Spatial Memory in Short-nosed Fruit Bat, Cynopterus sphinx. Zool Res 2010; 31:163-8. [DOI: 10.3724/sp.j.1141.2010.02163] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
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Barraquand F, Inchausti P, Bretagnolle V. Cognitive abilities of a central place forager interact with prey spatial aggregation in their effect on intake rate. Anim Behav 2009. [DOI: 10.1016/j.anbehav.2009.06.008] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Lührs ML, Dammhahn M, Kappeler PM, Fichtel C. Spatial memory in the grey mouse lemur (Microcebus murinus). Anim Cogn 2009; 12:599-609. [PMID: 19263100 PMCID: PMC2698973 DOI: 10.1007/s10071-009-0219-y] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2008] [Revised: 02/10/2009] [Accepted: 02/11/2009] [Indexed: 11/20/2022]
Abstract
Wild animals face the challenge of locating feeding sites distributed across broad spatial and temporal scales. Spatial memory allows animals to find a goal, such as a productive feeding patch, even when there are no goal-specific sensory cues available. Because there is little experimental information on learning and memory capabilities in free-ranging primates, the aim of this study was to test whether grey mouse lemurs (Microcebus murinus), as short-term dietary specialists, rely on spatial memory in relocating productive feeding sites. In addition, we asked what kind of spatial representation might underlie their orientation in their natural environment. Using an experimental approach, we set eight radio-collared grey mouse lemurs a memory task by confronting them with two different spatial patterns of baited and non-baited artificial feeding stations under exclusion of sensory cues. Positional data were recorded by focal animal observations within a grid system of small foot trails. A change in the baiting pattern revealed that grey mouse lemurs primarily used spatial cues to relocate baited feeding stations and that they were able to rapidly learn a new spatial arrangement. Spatially concentrated, non-random movements revealed preliminary evidence for a route-based restriction in mouse lemur space; during a subsequent release experiment, however, we found high travel efficiency in directed movements. We therefore propose that mouse lemur spatial memory is based on some kind of mental representation that is more detailed than a route-based network map.
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Affiliation(s)
- Mia-Lana Lührs
- Department of Sociobiology/Anthropology, Johann-Friedrich-Blumenbach-Institute for Zoology and Anthropology, University of Göttingen, Berliner Strasse 28, 37073, Göttingen, Germany.
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Neuroecology and diet selection in phyllostomid bats. Behav Processes 2009; 80:247-51. [DOI: 10.1016/j.beproc.2008.12.010] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2008] [Revised: 12/04/2008] [Accepted: 12/07/2008] [Indexed: 11/15/2022]
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Amrein I, Lipp HP. Adult hippocampal neurogenesis of mammals: evolution and life history. Biol Lett 2009; 5:141-4. [PMID: 18957357 PMCID: PMC2657751 DOI: 10.1098/rsbl.2008.0511] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2008] [Revised: 10/09/2008] [Accepted: 10/10/2008] [Indexed: 11/12/2022] Open
Abstract
Substantial production of new neurons in the adult mammalian brain is restricted to the olfactory system and the hippocampal formation. Its physiological and behavioural role is still debated. By comparing adult hippocampal neurogenesis (AHN) across many mammalian species, one might recognize a common function. AHN is most prominent in rodents, but shows considerable variability across species, being lowest or missing in primates and bats. The latter finding argues against a critical role of AHN in spatial learning and memory. The common functional denominator across all species investigated thus far is a strong decline of AHN from infancy to midlife. As predicted by Altman and colleagues in 1973, this implies a role in transforming juvenile unpredictable to predictable behaviour, typically characterizing mammalian behaviour once reproductive competence has been attained. However, as only a fraction of mammalian species has been investigated, further comparative studies are necessary in order to recognize whether AHN has a common unique function, or whether it mediates species-specific hippocampal functions.
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Affiliation(s)
| | - Hans-Peter Lipp
- Institute of Anatomy, University of Zurich-IrchelWinterthurerstrasse 190, CH-8057 Zurich, Switzerland
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Dalziel BD, Morales JM, Fryxell JM. Fitting probability distributions to animal movement trajectories: using artificial neural networks to link distance, resources, and memory. Am Nat 2008; 172:248-58. [PMID: 18598199 DOI: 10.1086/589448] [Citation(s) in RCA: 85] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
Animal movement paths are often thought of as a confluence of behavioral processes and landscape patterns. Yet it has proven difficult to develop frameworks for analyzing animal movement that can test these interactions. Here we describe a novel method for fitting movement models to data that can incorporate diverse aspects of landscapes and behavior. Using data from five elk (Cervus canadensis) reintroduced to central Ontario, we employed artificial neural networks to estimate movement probability kernels as functions of three landscape-behavioral processes. These consisted of measures of the animals' response to the physical spatial structure of the landscape, the spatial variability in resources, and memory of previously visited locations. The results support the view that animal movement results from interactions among elements of landscape structure and behavior, motivating context-dependent movement probabilities, rather than from successive realizations of static distributions, as some traditional models of movement and resource selection assume. Flexible, nonlinear models may thus prove useful in understanding the mechanisms controlling animal movement patterns.
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Ulanovsky N, Moss CF. What the bat's voice tells the bat's brain. Proc Natl Acad Sci U S A 2008; 105:8491-8. [PMID: 18562301 PMCID: PMC2438418 DOI: 10.1073/pnas.0703550105] [Citation(s) in RCA: 117] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2007] [Indexed: 11/18/2022] Open
Abstract
For over half a century, the echolocating bat has served as a valuable model in neuroscience to elucidate mechanisms of auditory processing and adaptive behavior in biological sonar. Our article emphasizes the importance of the bat's vocal-motor system to spatial orientation by sonar, and we present this view in the context of three problems that the echolocating bat must solve: (i) auditory scene analysis, (ii) sensorimotor transformations, and (iii) spatial memory and navigation. We summarize our research findings from behavioral studies of echolocating bats engaged in natural tasks and from neurophysiological studies of the bat superior colliculus and hippocampus, brain structures implicated in sensorimotor integration, orientation, and spatial memory. Our perspective is that studies of neural activity in freely vocalizing bats engaged in natural behaviors will prove essential to advancing a deeper understanding of the mechanisms underlying perception and memory in mammals.
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Affiliation(s)
- Nachum Ulanovsky
- *Department of Neurobiology, Weizmann Institute of Science, Rehovot 76100, Israel; and
| | - Cynthia F. Moss
- Department of Psychology and Institute for Systems Research, Program in Neuroscience and Cognitive Science, University of Maryland, College Park, MD 20742
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Waisman AS, Jacobs LF. Flexibility of cue use in the fox squirrel (Sciurus niger). Anim Cogn 2008; 11:625-36. [PMID: 18350324 DOI: 10.1007/s10071-008-0152-5] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2007] [Revised: 02/18/2008] [Accepted: 02/22/2008] [Indexed: 10/22/2022]
Abstract
Recent work on captive flying squirrels has demonstrated a novel degree of flexibility in the use of different orientation cues. In the present study, we examine to what extent this flexibility is present in a free-ranging population of another tree squirrel species, the fox squirrel. We trained squirrels to a rewarded location within a square array of four feeders and then tested them on transformations of the array that either pitted two cue types against one cue type, the majority tests, or all cue types against each other, the forced-hierarchy test. In Experiment 1, squirrels reoriented to the two-cue-type location in all majority tests and to the location indicated by the visual features of the feeders in the forced-hierarchy test. This preference for visual features runs contrary to previous studies that report the use of spatial cues over visual features in food-storing species. In Experiments 2-5 we tested squirrels with different trial orders (Experiments 2 and 3), a different apparatus (Experiment 4) and at different times of the year (Experiment 5) to determine why these squirrels had chosen to orient using visual features in the first experiment. Like captive flying squirrels, free-ranging fox squirrels showed a large degree of flexibility in their use of cues. Furthermore, their cue use appeared to be sensitive both to changes in the test apparatus and the season in which we tested. Altogether our results suggest that the study of free-ranging animals over a variety of conditions is necessary for understanding spatial cognition.
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Affiliation(s)
- Anna S Waisman
- Department of Psychology, University of California at Berkeley, Berkeley, CA 94720-1650, USA.
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Stich KP, Winter Y. Lack of generalization of object discrimination between spatial contexts by a bat. ACTA ACUST UNITED AC 2007; 209:4802-8. [PMID: 17114412 DOI: 10.1242/jeb.02574] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Discrimination and generalization are important elements of cognition in the daily lives of animals. Nectar-feeding bats detect flowers by olfaction and probably vision, but also use echolocation and echo-perception of flowers in immediate target surroundings. The echo received from an interference-rich flower corolla is a function of a bat's own relative position in space. This raises the question how easily a free-flying bat will generalize an echo stimulus from a learning situation to a new spatial context where differences in relative flight approach trajectories may lead to an unfamiliar spectral composition of the self-generated echoes. We trained free-flying Glossophaga soricina in echoacoustic discrimination in a two-alternative forced-choice (2-AFC) paradigm at location A. We then tested at location B for spontaneous transfer of discrimination ability. Bats did not spontaneously transfer the discrimination ability acquired at A to location B. This lack of spontaneous generalization may have been caused by factors of the underlying learning mechanisms. 2-AFC tasks may not be representative of the natural foraging behaviour of flower-visiting bats. In contrast to insect-eating bats that constantly evaluate the environment to detect unpredictable prey, the spatial stability of flowers may allow flower visitors to rely on spatial memory to guide foraging. The 2-AFC task requires the disregard (learned irrelevance) of salient spatial location cues that are different at each new location. In Glossophaga, a conjunction between spatial context and 2-AFC discrimination learning may have inhibited the transfer of learned irrelevance of spatial location in the 2-AFC task to new spatial locations. Alternatively, the bats may have learnt the second discrimination task completely anew, and were faster only because of an acquired learning set. We suggest a dissociation between 2-AFC task acquisition and novel object discrimination learning to resolve the issue.
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Amrein I, Dechmann DK, Winter Y, Lipp HP. Absent or low rate of adult neurogenesis in the hippocampus of bats (Chiroptera). PLoS One 2007; 2:e455. [PMID: 17520014 PMCID: PMC1866182 DOI: 10.1371/journal.pone.0000455] [Citation(s) in RCA: 100] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2006] [Accepted: 04/13/2007] [Indexed: 11/19/2022] Open
Abstract
Bats are the only flying mammals and have well developed navigation abilities for 3D-space. Even bats with comparatively small home ranges cover much larger territories than rodents, and long-distance migration by some species is unique among small mammals. Adult proliferation of neurons, i.e., adult neurogenesis, in the dentate gyrus of rodents is thought to play an important role in spatial memory and learning, as indicated by lesion studies and recordings of neurons active during spatial behavior. Assuming a role of adult neurogenesis in hippocampal function, one might expect high levels of adult neurogenesis in bats, particularly among fruit- and nectar-eating bats in need of excellent spatial working memory. The dentate gyrus of 12 tropical bat species was examined immunohistochemically, using multiple antibodies against proteins specific for proliferating cells (Ki-67, MCM2), and migrating and differentiating neurons (Doublecortin, NeuroD). Our data show a complete lack of hippocampal neurogenesis in nine of the species (Glossophaga soricina, Carollia perspicillata, Phyllostomus discolor, Nycteris macrotis, Nycteris thebaica, Hipposideros cyclops, Neoromicia rendalli, Pipistrellus guineensis, and Scotophilus leucogaster), while it was present at low levels in three species (Chaerephon pumila, Mops condylurus and Hipposideros caffer). Although not all antigens were recognized in all species, proliferation activity in the subventricular zone and rostral migratory stream was found in all species, confirming the appropriateness of our methods for detecting neurogenesis. The small variation of adult hippocampal neurogenesis within our sample of bats showed no indication of a correlation with phylogenetic relationship, foraging strategy, type of hunting habitat or diet. Our data indicate that the widely accepted notion of adult neurogenesis supporting spatial abilities needs to be considered carefully. Given their astonishing longevity, certain bat species may be useful subjects to compare adult neurogenesis with other long-living species, such as monkeys and humans, showing low rates of adult hippocampal neurogenesis.
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Affiliation(s)
- Irmgard Amrein
- University of Zurich, Institute of Anatomy, Division of Neuroanatomy and Behavior, Zurich, Switzerland
| | - Dina K.N. Dechmann
- University of Zurich, Institute of Anatomy, Division of Neuroanatomy and Behavior, Zurich, Switzerland
| | - York Winter
- Department of Biology, University of Munich, Munich, Germany
| | - Hans-Peter Lipp
- University of Zurich, Institute of Anatomy, Division of Neuroanatomy and Behavior, Zurich, Switzerland
- * To whom correspondence should be addressed. E-mail:
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Winter Y, von Merten S, Kleindienst HU. Visual landmark orientation by flying bats at a large-scale touch and walk screen for bats, birds and rodents. J Neurosci Methods 2005; 141:283-90. [PMID: 15661311 DOI: 10.1016/j.jneumeth.2004.07.002] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2004] [Revised: 07/01/2004] [Accepted: 07/02/2004] [Indexed: 11/29/2022]
Abstract
Orientation depends on multi-modal information about the locally perceptible environment (local view) in many situations. We developed a behavioural paradigm for investigating visual orientation of flying bats based on a large-scale touch screen (1.2 m x 1.8 m). It functions by a grid of rows and columns of infra-red beams just in front of a screen with back-projected visual stimuli. Approaching animals interrupt the beams and thus permit automatic recording of the time and place of an animal's locational choice. We used it as a vertical touch surface. Installed as a horizontal walk surface, it may also serve as a more natural 'firm ground', circular arena analogue to the 'Morris water maze' for investigating orientation behaviour and spatial cognition from rodents to birds while offering automatic real-time recording of paths, times and latencies with enhanced possibilities to score details of motor behaviour and to control stimuli interactively. Bats offer a unique possibility to investigate the use of both echo-acoustic and visual information processing pathways for the process of self-localization and orientation. In our first experiment, a bat was presented with five identical targets, one central and four peripheral and had to choose the central target. After task acquisition, the array was shifted by the distance between targets, so that a formerly peripheral landmark was now in the absolute location of the formerly central target. At small inter-target distances, the bat 'went with' the array, and chose the new central target (at a new absolute location). With 30 cm or more of inter-target distance (60 cm across the landmark configuration), however, the bat went with absolute location, and chose a peripheral target. In experiment 2, the bat was presented with two landmarks 30 cm apart and an unmarked target located at midline beneath them. On tests, the landmarks either maintained training distance or were expanded to 50 cm apart. On such expansion tests, the bat chose most the location at the correct vector from the right landmark. This showed that the bat first identified a single landmark by the configuration and then applied a previously learnt vector (angle and distance) to locate the target. Glossophaga did not orient by pure angular geometry between landmarks and target.
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Affiliation(s)
- York Winter
- Department of Biology, University of Munich, Germany.
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