1
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Lynch LM, Allen KL. Relative Brain Volume of Carnivorans Has Evolved in Correlation with Environmental and Dietary Variables Differentially among Clades. BRAIN, BEHAVIOR AND EVOLUTION 2022; 97:284-297. [PMID: 35235933 DOI: 10.1159/000523787] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/25/2021] [Accepted: 02/16/2022] [Indexed: 12/21/2022]
Abstract
Carnivorans possess relatively large brains compared to most other mammalian clades. Factors like environmental complexity (Cognitive Buffer Hypothesis) and diet quality (Expensive-Tissue Hypothesis) have been proposed as mechanisms for encephalization in other large-brained clades. We examine whether the Cognitive Buffer and Expensive-Tissue Hypotheses account for brain size variation within Carnivora. Under these hypotheses, we predict a positive correlation between brain size and environmental complexity or protein consumption. Relative endocranial volume (phylogenetic generalized least-squares residual from species' mean body mass) and 9 environmental and dietary variables were collected from the literature for 148 species of terrestrial and marine carnivorans. We found that the correlation between relative brain volume and environment and diet differed among clades, a trend consistent with other larger brained vertebrates (i.e., Primates, Aves). Mustelidae and Procyonidae demonstrate larger brains in species with higher-quality diets, consistent with the Expensive-Tissue Hypothesis, while in Herpestidae, correlations between relative brain size and environment are consistent with the Cognitive Buffer Hypothesis. Our results indicate that carnivorans may have evolved relatively larger brains under similar selective pressures as primates despite the considerable differences in life history and behavior between these two clades.
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Affiliation(s)
- Leigha M Lynch
- Washington University School of Medicine in St. Louis, St. Louis, Missouri, USA.,Midwestern University, Glendale, Arizona, USA
| | - Kari L Allen
- Washington University School of Medicine in St. Louis, St. Louis, Missouri, USA
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2
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Using a Phylogenetic Framework to Assess the Role of Fruit Size in Food Selection by the Andean Night Monkey (Aotus lemurinus). INT J PRIMATOL 2022. [DOI: 10.1007/s10764-021-00274-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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3
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Abstract
Abstract
Brain size exhibits significant changes within and between species. Evolution of large brains can be explained by the need to improve cognitive ability for processing more information in changing environments. However, brains are among the most energetically expensive organs. Enlarged brains can impose energetic demands that limit brain size evolution. The expensive tissue hypothesis (ETH) states that a decrease in the size of another expensive tissue, such as the gut, should compensate for the cost of a large brain. We studied the interplay between energetic limitations and brain size evolution in small mammals using phylogenetically generalized least squares (PGLS) regression analysis. Brain mass was not correlated with the length of the digestive tract in 37 species of small mammals after correcting for phylogenetic relationships and body size effects. We further found that the evolution of a large brain was not accompanied by a decrease in male reproductive investments into testes mass and in female reproductive investment into offspring number. The evolution of brain size in small mammals is inconsistent with the prediction of the ETH.
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4
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Parvimico materdei gen. et sp. nov.: A new platyrrhine from the Early Miocene of the Amazon Basin, Peru. J Hum Evol 2019; 134:102628. [DOI: 10.1016/j.jhevol.2019.05.016] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2018] [Revised: 05/31/2019] [Accepted: 05/31/2019] [Indexed: 11/21/2022]
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5
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Aristide L, Strauss A, Halenar-Price LB, Gilissen E, Cruz FW, Cartelle C, Rosenberger AL, Lopes RT, Dos Reis SF, Perez SI. Cranial and endocranial diversity in extant and fossil atelids (Platyrrhini: Atelidae): A geometric morphometric study. AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY 2019; 169:322-331. [PMID: 30972753 DOI: 10.1002/ajpa.23837] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/09/2018] [Revised: 02/14/2019] [Accepted: 03/31/2019] [Indexed: 01/17/2023]
Abstract
OBJECTIVES Platyrrhines constitute a diverse clade, with the modern Atelidae exhibiting the most variation in cranial and endocast morphology. The processes responsible for this diversification are not well understood. Here, we present a geometric morphometric study describing variation in cranial and endocranial shape of 14 species of Alouatta, Ateles, Brachyteles, and Lagothrix and two extinct taxa, Cartelles and Caipora. METHODS We examined cranial and endocranial shape variation among species using images reconstructed from CT scans and geometric morphometric techniques based on three-dimensional landmarks and semilandmarks. Principal components analyses were used to explore variation, including the Procrustes shape coordinates, summing the logarithm of the Centroid Size, the common allometric component, and residual shape components. RESULTS Differences in endocranial shape are related to a relative increase or decrease in the volume of the neocortex region with respect to brainstem and cerebellum regions. The relative position of the brainstem varies from a posterior position in Alouatta to a more ventral position in Ateles. The shape of both the cranium and endocast of Caipora is within the observed variation of Brachyteles. Cartelles occupies the most differentiated position relative to the extant taxa, especially in regards to its endocranial shape. CONCLUSIONS The pattern of variation in the extant species in endocranial shape is similar to the variation observed in previous cranial studies, with Alouatta as an outlier. The similarities between Caipora and Brachyteles were unexpected and intriguing given the frugivorous adaptations inferred from the fossil's dentition. Our study shows the importance of considering both extant and fossil species when studying diversification of complex traits.
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Affiliation(s)
- Leandro Aristide
- División Antropología (FCNyM-UNLP), CONICET, La Plata, Argentina.,Institut de biologie de l'Ecole normale supérieure (IBENS), Ecole normale supérieure, CNRS, INSERM, PSL Université Paris, Paris, France
| | - André Strauss
- Museu de Arqueologia e Etnologia, Universidade de São Paulo, São Paulo, Brazil.,Instituto de Biociências, Universidade de São Paulo, São Paulo, Brazil.,Palaeoanthropology Senckenberg Centre for Human Evolution and Palaeoenvironment, Eberhard Karls Universität Tübingen, Tübingen, Germany
| | - Lauren B Halenar-Price
- Department of Biology, Farmingdale State College (SUNY), New York, New York.,NYCEP Morphometrics Group, New York, NY
| | - Emmanuel Gilissen
- Department of African Zoology, Royal Museum for Central Africa, Tervuren, Belgium.,Laboratory of Histology and Neuropathology, Université Libre de Bruxelles, Brussels, Belgium
| | - Francisco W Cruz
- Instituto de Geociências, Universidade de São Paulo, São Paulo, Brazil
| | - Castor Cartelle
- Museu de Ciências Naturais, Pontificia Universidade Católica de Minas Gerais, Belo Horizonte, Brazil
| | - Alfred L Rosenberger
- NYCEP Morphometrics Group, New York, NY.,Department of Anthropology, City of New York Graduate Center, New York, New York
| | - Ricardo T Lopes
- Laboratório de Instrumentação Nuclear, Centro de Tecnologia (UFRJ), Río de Janeiro, Brazil
| | | | - S Ivan Perez
- División Antropología (FCNyM-UNLP), CONICET, La Plata, Argentina.,Instituto de Física 'Gleb Wataghin' (UNICAMP), Campinas, Brazil
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6
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Halenar-Price L, Tallman M. Investigating the effect of endocranial volume on cranial shape in platyrrhines and the relevance of this relationship to interpretations of the fossil record. AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY 2019; 169:12-30. [PMID: 30802306 DOI: 10.1002/ajpa.23804] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/17/2018] [Revised: 12/31/2018] [Accepted: 02/06/2019] [Indexed: 11/10/2022]
Abstract
OBJECTIVES Fossils have been linked to Alouatta based on shared cranial morphology and small brain size. However, the relationship between endocranial volume and cranial shape is unclear; it is possible that any platyrrhine with a small brain may exhibit "Alouatta-like" features due to being "de-encephalized." We test two hypotheses: (a) there are aspects of cranial shape related to encephalization common to all platyrrhines; (b) it is these cranial traits that unite the small-brained "Alouatta-like" fossils. MATERIALS AND METHODS Three-dimensional cranial shape and endocranial volume (ECV) were measured on 350+ extant platyrrhine crania, Cartelles, Paralouatta, and Antillothrix. Encephalization quotient (EQ) was calculated using regressions of ECV on cranial centroid size. Multivariate regressions were performed using the shape coordinates and EQ and shape changes associated with EQ were visualized. Cranial shape was predicted for a hypothetical primate with an EQ matching the fossils and this shape was compared to the Alouatta mean. RESULTS There is a significant proportion of cranial shape variation explained by EQ in some taxa. The aspects of shape that are correlated with EQ are shared by several taxa and some have parallel regression vectors, but there is no overall pattern of shape change common to all platyrrhines. However, all taxa look more similar to Alouatta when their EQ is decreased, particularly Pithecia. DISCUSSION Given that a decrease in encephalization can cause a more Alouatta-like cranial shape in many extant platyrrhines, it should not be automatically assumed that Alouatta-like cranial traits in a small-brained fossil are evidence of a phylogenetic link to the alouattin clade.
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Affiliation(s)
- Lauren Halenar-Price
- Department of Biology, Farmingdale State College (SUNY), Farmingdale, New York.,NYCEP Morphometrics Group, New York, New York
| | - Melissa Tallman
- NYCEP Morphometrics Group, New York, New York.,Department of Biomedical Sciences, Grand Valley State University, Allendale, Michigan
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7
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Veneziano A, Irish JD, Meloro C, Stringer C, De Groote I. The functional significance of dental and mandibular reduction in
Homo
: A catarrhine perspective. Am J Primatol 2019; 81:e22953. [DOI: 10.1002/ajp.22953] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2018] [Revised: 12/07/2018] [Accepted: 12/22/2018] [Indexed: 11/09/2022]
Affiliation(s)
- Alessio Veneziano
- School of Natural Sciences and PsychologyLiverpool John Moores UniversityLiverpoolUK
| | - Joel D. Irish
- School of Natural Sciences and PsychologyLiverpool John Moores UniversityLiverpoolUK
- Evolutionary Studies Institute and Centre for Excellence in PaleoSciencesUniversity of the Witwatersrand, Private Bag 3, WITS 2050JohannesburgSouth Africa
| | - Carlo Meloro
- School of Natural Sciences and PsychologyLiverpool John Moores UniversityLiverpoolUK
| | - Chris Stringer
- Department of Earth SciencesThe Natural History MuseumLondonUK
| | - Isabelle De Groote
- School of Natural Sciences and PsychologyLiverpool John Moores UniversityLiverpoolUK
- Department of Earth SciencesThe Natural History MuseumLondonUK
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8
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Aristide L, Bastide P, Dos Reis SF, Pires Dos Santos TM, Lopes RT, Perez SI. Multiple factors behind early diversification of skull morphology in the continental radiation of New World monkeys. Evolution 2018; 72:2697-2711. [PMID: 30246282 DOI: 10.1111/evo.13609] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2017] [Accepted: 09/03/2018] [Indexed: 01/24/2023]
Abstract
Understanding the origin of diversity is a fundamental problem in evolutionary biology. The null expectation for the evolutionary diversification is that all changes in biological diversity are the result of random processes. Adaptive radiations depart from this expectation as ecological factors and natural selection are supposed to play a central role in driving exceptional diversification. However, it is not well understood how large-scale continental radiations, given their characteristics, fit to these opposing theoretical models. Here, we used phylogenetic comparative methods and geometric morphometrics to study the evolutionary process of cranial diversification in the continental radiation of New World monkeys. Particularly, we tested several alternative evolutionary scenarios for morphological evolution in the clade. Results indicated that despite the platyrrhine radiation being old and geographically widespread, the formative patterns arising from the initial stages of diversification probably associated with an adaptive radiation can still be recognized today. We also show that no single explored factor (e.g., ecological or allometric) can be invoked as a complete explanation for the observed phenotypic diversity patterns in the clade and, moreover, that different cranial regions exhibit particular macroevolutionary patterns. Together, our results highlight the evident complexity behind large-scale evolutionary radiations.
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Affiliation(s)
- Leandro Aristide
- División Antropología, Facultad de Ciencias Naturales y Museo, Universidad Nacional de La Plata, Consejo Nacional de Investigaciones Científicas y Técnicas, 1900 La Plata, Buenos Aires, Argentina.,École Normale Supérieure, Paris Sciences et Lettres (PSL) Research University, Institut de Biologie de l'École Normale Supérieure (IBENS), CNRS UMR 8197, INSERM U1024, 46 rue d'Ulm, F-75005, Paris, France
| | - Paul Bastide
- Department of Microbiology and Immunology, Rega Institute, KU Leuven - University of Leuven, Herestraat 49 box 1030 BE-3000, Leuven, Belgium
| | - Sergio Furtado Dos Reis
- Departamento de Biologia Animal, Universidade Estadual de Campinas, CEP 13.083-862 Campinas, São Paulo, Brazil
| | - Thaís M Pires Dos Santos
- Laboratório de Instrumentação Nuclear, Centro de Tecnologia, Universidade Federal do Rio de Janeiro, Ilha do Fundão, CEP 21949-900, Rio de Janeiro, Brazil
| | - Ricardo T Lopes
- Laboratório de Instrumentação Nuclear, Centro de Tecnologia, Universidade Federal do Rio de Janeiro, Ilha do Fundão, CEP 21949-900, Rio de Janeiro, Brazil
| | - S Ivan Perez
- División Antropología, Facultad de Ciencias Naturales y Museo, Universidad Nacional de La Plata, Consejo Nacional de Investigaciones Científicas y Técnicas, 1900 La Plata, Buenos Aires, Argentina
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9
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Püschel TA, Gladman JT, Bobe R, Sellers WI. The evolution of the platyrrhine talus: A comparative analysis of the phenetic affinities of the Miocene platyrrhines with their modern relatives. J Hum Evol 2017; 111:179-201. [PMID: 28874270 PMCID: PMC5603972 DOI: 10.1016/j.jhevol.2017.07.015] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2016] [Revised: 07/21/2017] [Accepted: 07/26/2017] [Indexed: 01/08/2023]
Abstract
Platyrrhines are a diverse group of primates that presently occupy a broad range of tropical-equatorial environments in the Americas. However, most of the fossil platyrrhine species of the early Miocene have been found at middle and high latitudes. Although the fossil record of New World monkeys has improved considerably over the past several years, it is still difficult to trace the origin of major modern clades. One of the most commonly preserved anatomical structures of early platyrrhines is the talus. This work provides an analysis of the phenetic affinities of extant platyrrhine tali and their Miocene counterparts through geometric morphometrics and a series of phylogenetic comparative analyses. Geometric morphometrics was used to quantify talar shape affinities, while locomotor mode percentages (LMPs) were used to test if talar shape is associated with locomotion. Comparative analyses were used to test if there was convergence in talar morphology, as well as different models that could explain the evolution of talar shape and size in platyrrhines. Body mass predictions for the fossil sample were also computed using the available articular surfaces. The results showed that most analyzed fossils exhibit a generalized morphology that is similar to some 'generalist' modern species. It was found that talar shape covaries with LMPs, thus allowing the inference of locomotion from talar morphology. The results further suggest that talar shape diversification can be explained by invoking a model of shifts in adaptive peak to three optima representing a phylogenetic hypothesis in which each platyrrhine family occupied a separate adaptive peak. The analyses indicate that platyrrhine talar centroid size diversification was characterized by an early differentiation related to a multidimensional niche model. Finally, the ancestral platyrrhine condition was reconstructed as a medium-sized, generalized, arboreal, quadruped.
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Affiliation(s)
- Thomas A Püschel
- School of Earth and Environmental Sciences, University of Manchester, M13 9PL, United Kingdom.
| | - Justin T Gladman
- Department of Anthropology, The Graduate Center, CUNY, New York, NY, USA; NYCEP, New York Consortium in Evolutionary Primatology, New York, NY, USA
| | - René Bobe
- Departamento de Antropología, Universidad de Chile, Santiago, Chile; Institute of Cognitive and Evolutionary Anthropology, School of Anthropology, University of Oxford, United Kingdom
| | - William I Sellers
- School of Earth and Environmental Sciences, University of Manchester, M13 9PL, United Kingdom
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10
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Beston SM, Broyles W, Walsh MR. Increased juvenile predation is not associated with evolved differences in adult brain size in Trinidadian killifish ( Rivulus hartii). Ecol Evol 2017; 7:884-894. [PMID: 28168025 PMCID: PMC5288286 DOI: 10.1002/ece3.2668] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2016] [Revised: 11/02/2016] [Accepted: 11/05/2016] [Indexed: 11/12/2022] Open
Abstract
Vertebrates exhibit extensive variation in brain size. The long-standing assumption is that this variation is driven by ecologically mediated selection. Recent work has shown that an increase in predator-induced mortality is associated with evolved increases and decreases in brain size. Thus, the manner in which predators induce shifts in brain size remains unclear. Increased predation early in life is a key driver of many adult traits, including life-history and behavioral traits. Such results foreshadow a connection between age-specific mortality and selection on adult brain size. Trinidadian killifish, Rivulus hartii, are found in sites with and without guppies, Poecilia reticulata. The densities of Rivulus drop dramatically in sites with guppies because guppies prey upon juvenile Rivulus. Previous work has shown that guppy predation is associated with the evolution of adult life-history traits in Rivulus. In this study, we compared second-generation laboratory-born Rivulus from sites with and without guppies for differences in brain size and associated trade-offs between brain size and other components of fitness. Despite the large amount of existing research on the importance of early-life events on the evolution of adult traits, and the role of predation on both behavior and brain size, we did not find an association between the presence of guppies and evolutionary shifts in Rivulus brain size. Such results argue that increased rates of juvenile mortality may not alter selection on adult brain size.
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Affiliation(s)
| | - Whitnee Broyles
- Department of BiologyUniversity of Texas at ArlingtonArlingtonTXUSA
| | - Matthew R. Walsh
- Department of BiologyUniversity of Texas at ArlingtonArlingtonTXUSA
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11
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Liao WB, Lou SL, Zeng Y, Kotrschal A. Large Brains, Small Guts: The Expensive Tissue Hypothesis Supported within Anurans. Am Nat 2016; 188:693-700. [DOI: 10.1086/688894] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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12
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Abstract
Primates constitute one of the most diverse mammalian clades, and a notable feature of their diversification is the evolution of brain morphology. However, the evolutionary processes and ecological factors behind these changes are largely unknown. In this work, we investigate brain shape diversification of New World monkeys during their adaptive radiation in relation to different ecological dimensions. Our results reveal that brain diversification in this clade can be explained by invoking a model of adaptive peak shifts to unique and shared optima, defined by a multidimensional ecological niche hypothesis. Particularly, we show that the evolution of convergent brain phenotypes may be related to ecological factors associated with group size (e.g., social complexity). Together, our results highlight the complexity of brain evolution and the ecological significance of brain shape changes during the evolutionary diversification of a primate clade.
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13
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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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14
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Liao WB, Lou SL, Zeng Y, Merilä J. Evolution of anuran brains: disentangling ecological and phylogenetic sources of variation. J Evol Biol 2015; 28:1986-96. [PMID: 26248891 DOI: 10.1111/jeb.12714] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2014] [Revised: 07/12/2015] [Accepted: 08/01/2015] [Indexed: 02/06/2023]
Abstract
Variation in ecological selection pressures has been implicated to explain variation in brain size and architecture in fishes, birds and mammals, but little is known in this respect about amphibians. Likewise, the relative importance of constraint vs. mosaic hypotheses of brain evolution in explaining variation in brain size and architecture remains contentious. Using phylogenetic comparative methods, we studied interspecific variation in brain size and size of different brain parts among 43 Chinese anuran frogs and explored how much of this variation was explainable by variation in ecological factors (viz. habitat type, diet and predation risk). We also evaluated which of the two above-mentioned hypotheses best explains the observed patterns. Although variation in brain size explained on average 80.5% of the variation in size of different brain parts (supporting the constraint hypothesis), none of the three ecological factors were found to explain variation in overall brain size. However, habitat and diet type explained a significant amount of variation in telencephalon size, as well in three composite measures of brain architecture. Likewise, predation risk explained a significant amount of variation in bulbus olfactorius and optic tecta size. Our results show that evolution of anuran brain accommodates features compatible with both constraint (viz. strong allometry among brain parts) and mosaic (viz. independent size changes in response to ecological factors in certain brain parts) models of brain size evolution.
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Affiliation(s)
- W B Liao
- Key Laboratory of Southwest China Wildlife Resources Conservation (Ministry of Education), China West Normal University, Nanchong, Sichuan, China.,Ecological Genetics Research Unit, Department of Biosciences, University of Helsinki, Helsinki, Finland
| | - S L Lou
- Key Laboratory of Southwest China Wildlife Resources Conservation (Ministry of Education), China West Normal University, Nanchong, Sichuan, China
| | - Y Zeng
- Key Laboratory of Southwest China Wildlife Resources Conservation (Ministry of Education), China West Normal University, Nanchong, Sichuan, China
| | - J Merilä
- Ecological Genetics Research Unit, Department of Biosciences, University of Helsinki, Helsinki, Finland
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15
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Abstract
The world of primate genomics is expanding rapidly in new and exciting ways owing to lowered costs and new technologies in molecular methods and bioinformatics. The primate order is composed of 78 genera and 478 species, including human. Taxonomic inferences are complex and likely a consequence of ongoing hybridization, introgression, and reticulate evolution among closely related taxa. Recently, we applied large-scale sequencing methods and extensive taxon sampling to generate a highly resolved phylogeny that affirms, reforms, and extends previous depictions of primate speciation. The next stage of research uses this phylogeny as a foundation for investigating genome content, structure, and evolution across primates. Ongoing and future applications of a robust primate phylogeny are discussed, highlighting advancements in adaptive evolution of genes and genomes, taxonomy and conservation management of endangered species, next-generation genomic technologies, and biomedicine.
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Affiliation(s)
- Jill Pecon-Slattery
- Laboratory of Genomic Diversity, National Cancer Institute, Frederick, Maryland 21702; Current Affiliation: Smithsonian Conservation Biology Institute, National Zoological Park, Front Royal, Virginia 22630;
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16
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Encephalization and diversification of the cranial base in platyrrhine primates. J Hum Evol 2015; 81:29-40. [DOI: 10.1016/j.jhevol.2015.02.003] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2014] [Revised: 02/02/2015] [Accepted: 02/03/2015] [Indexed: 11/19/2022]
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17
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Allen KL, Cooke SB, Gonzales LA, Kay RF. Dietary inference from upper and lower molar morphology in platyrrhine primates. PLoS One 2015; 10:e0118732. [PMID: 25738266 PMCID: PMC4349698 DOI: 10.1371/journal.pone.0118732] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2014] [Accepted: 01/22/2015] [Indexed: 11/24/2022] Open
Abstract
The correlation between diet and dental topography is of importance to paleontologists seeking to diagnose ecological adaptations in extinct taxa. Although the subject is well represented in the literature, few studies directly compare methods or evaluate dietary signals conveyed by both upper and lower molars. Here, we address this gap in our knowledge by comparing the efficacy of three measures of functional morphology for classifying an ecologically diverse sample of thirteen medium- to large-bodied platyrrhines by diet category (e.g., folivore, frugivore, hard object feeder). We used Shearing Quotient (SQ), an index derived from linear measurements of molar cutting edges and two indices of crown surface topography, Occlusal Relief (OR) and Relief Index (RFI). Using SQ, OR, and RFI, individuals were then classified by dietary category using Discriminate Function Analysis. Both upper and lower molar variables produce high classification rates in assigning individuals to diet categories, but lower molars are consistently more successful. SQs yield the highest classification rates. RFI and OR generally perform above chance. Upper molar RFI has a success rate below the level of chance. Adding molar length enhances the discriminatory power for all variables. We conclude that upper molar SQs are useful for dietary reconstruction, especially when combined with body size information. Additionally, we find that among our sample of platyrrhines, SQ remains the strongest predictor of diet, while RFI is less useful at signaling dietary differences in absence of body size information. The study demonstrates new ways for inferring the diets of extinct platyrrhine primates when both upper and lower molars are available, or, for taxa known only from upper molars. The techniques are useful in reconstructing diet in stem representatives of anthropoid clade, who share key aspects of molar morphology with extant platyrrhines.
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Affiliation(s)
- Kari L. Allen
- Department of Anatomy & Neurobiology, Washington University Medical School, 660 S. Euclid Ave., Box 8108, St. Louis, Missouri 63110, United States of America
| | - Siobhán B. Cooke
- Department of Anthropology, Northeastern Illinois University, 5500 N. St. Louis Avenue Chicago, Illinois 60625, United States of America
| | - Lauren A. Gonzales
- Department of Evolutionary Anthropology, Duke University, Box 90383, Durham, North Carolina 27708, United States of America
| | - Richard F. Kay
- Department of Evolutionary Anthropology, Duke University, Box 90383, Durham, North Carolina 27708, United States of America
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18
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Tsuboi M, Husby A, Kotrschal A, Hayward A, Buechel SD, Zidar J, Løvlie H, Kolm N. Comparative support for the expensive tissue hypothesis: Big brains are correlated with smaller gut and greater parental investment in Lake Tanganyika cichlids. Evolution 2014; 69:190-200. [PMID: 25346264 PMCID: PMC4312921 DOI: 10.1111/evo.12556] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2014] [Accepted: 10/10/2014] [Indexed: 02/06/2023]
Abstract
The brain is one of the most energetically expensive organs in the vertebrate body. Consequently, the energetic requirements of encephalization are suggested to impose considerable constraints on brain size evolution. Three main hypotheses concerning how energetic constraints might affect brain evolution predict covariation between brain investment and (1) investment into other costly tissues, (2) overall metabolic rate, and (3) reproductive investment. To date, these hypotheses have mainly been tested in homeothermic animals and the existing data are inconclusive. However, there are good reasons to believe that energetic limitations might play a role in large-scale patterns of brain size evolution also in ectothermic vertebrates. Here, we test these hypotheses in a group of ectothermic vertebrates, the Lake Tanganyika cichlid fishes. After controlling for the effect of shared ancestry and confounding ecological variables, we find a negative association between brain size and gut size. Furthermore, we find that the evolution of a larger brain is accompanied by increased reproductive investment into egg size and parental care. Our results indicate that the energetic costs of encephalization may be an important general factor involved in the evolution of brain size also in ectothermic vertebrates.
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Affiliation(s)
- Masahito Tsuboi
- Evolutionary Biology Centre, Department of Ecology and Genetics/Animal Ecology, Uppsala University, Norbyvägen 18D, SE-75236, Uppsala, Sweden.
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Herczeg G, Välimäki K, Gonda A, Merilä J. Evidence for sex-specific selection in brain: a case study of the nine-spined stickleback. J Evol Biol 2014; 27:1604-12. [DOI: 10.1111/jeb.12409] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2013] [Revised: 04/04/2014] [Accepted: 04/13/2014] [Indexed: 11/30/2022]
Affiliation(s)
- G. Herczeg
- Behavioural Ecology Group; Department of Systematic Zoology and Ecology; Eötvös Loránd University; Budapest Hungary
- Ecological Genetics Research Unit; Department of Biosciences; University of Helsinki; Helsinki Finland
| | - K. Välimäki
- Ecological Genetics Research Unit; Department of Biosciences; University of Helsinki; Helsinki Finland
- Monitoring Team; Finnish Museum of Natural History; University of Helsinki; Helsinki Finland
| | - A. Gonda
- Ecological Genetics Research Unit; Department of Biosciences; University of Helsinki; Helsinki Finland
| | - J. Merilä
- Ecological Genetics Research Unit; Department of Biosciences; University of Helsinki; Helsinki Finland
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20
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van Woerden JT, van Schaik CP, Isler K. Brief Communication: Seasonality of diet composition is related to brain size in New World Monkeys. AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY 2014; 154:628-32. [DOI: 10.1002/ajpa.22546] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/28/2014] [Accepted: 05/20/2014] [Indexed: 11/07/2022]
Affiliation(s)
| | - Carel P. van Schaik
- Anthropological Institute and Museum; University of Zurich; CH-8057 Zurich Switzerland
| | - Karin Isler
- Anthropological Institute and Museum; University of Zurich; CH-8057 Zurich Switzerland
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21
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MacLean EL, Hare B, Nunn CL, Addessi E, Amici F, Anderson RC, Aureli F, Baker JM, Bania AE, Barnard AM, Boogert NJ, Brannon EM, Bray EE, Bray J, Brent LJN, Burkart JM, Call J, Cantlon JF, Cheke LG, Clayton NS, Delgado MM, DiVincenti LJ, Fujita K, Herrmann E, Hiramatsu C, Jacobs LF, Jordan KE, Laude JR, Leimgruber KL, Messer EJE, Moura ACDA, Ostojić L, Picard A, Platt ML, Plotnik JM, Range F, Reader SM, Reddy RB, Sandel AA, Santos LR, Schumann K, Seed AM, Sewall KB, Shaw RC, Slocombe KE, Su Y, Takimoto A, Tan J, Tao R, van Schaik CP, Virányi Z, Visalberghi E, Wade JC, Watanabe A, Widness J, Young JK, Zentall TR, Zhao Y. The evolution of self-control. Proc Natl Acad Sci U S A 2014; 111:E2140-8. [PMID: 24753565 PMCID: PMC4034204 DOI: 10.1073/pnas.1323533111] [Citation(s) in RCA: 427] [Impact Index Per Article: 42.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Cognition presents evolutionary research with one of its greatest challenges. Cognitive evolution has been explained at the proximate level by shifts in absolute and relative brain volume and at the ultimate level by differences in social and dietary complexity. However, no study has integrated the experimental and phylogenetic approach at the scale required to rigorously test these explanations. Instead, previous research has largely relied on various measures of brain size as proxies for cognitive abilities. We experimentally evaluated these major evolutionary explanations by quantitatively comparing the cognitive performance of 567 individuals representing 36 species on two problem-solving tasks measuring self-control. Phylogenetic analysis revealed that absolute brain volume best predicted performance across species and accounted for considerably more variance than brain volume controlling for body mass. This result corroborates recent advances in evolutionary neurobiology and illustrates the cognitive consequences of cortical reorganization through increases in brain volume. Within primates, dietary breadth but not social group size was a strong predictor of species differences in self-control. Our results implicate robust evolutionary relationships between dietary breadth, absolute brain volume, and self-control. These findings provide a significant first step toward quantifying the primate cognitive phenome and explaining the process of cognitive evolution.
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Affiliation(s)
| | - Brian Hare
- Departments of Evolutionary Anthropology,Center for Cognitive Neuroscience
| | | | - Elsa Addessi
- Istituto di Scienze e Tecnologie della Cognizione Consiglio Nazionale delle Ricerche, 00197 Rome, Italy
| | - Federica Amici
- Department of Developmental and Comparative Psychology, Max Planck Institute for Evolutionary Anthropology, D-04103 Leipzig, Germany
| | | | - Filippo Aureli
- Instituto de Neuroetologia, Universidad Veracruzana, Xalapa, CP 91190, Mexico;Research Centre in Evolutionary Anthropology and Palaeoecology, Liverpool John Moores University, Liverpool L3 3AF, United Kingdom
| | - Joseph M Baker
- Center for Interdisciplinary Brain Sciences Research andDepartment of Psychiatry and Behavioral Sciences, Stanford University School of Medicine, Stanford, CA 94305
| | - Amanda E Bania
- Center for Animal Care Sciences, Smithsonian National Zoological Park, Washington, DC 20008
| | | | - Neeltje J Boogert
- Department of Psychology and Neuroscience, University of St. Andrews, St. Andrews KY16 9JP, Scotland
| | | | - Emily E Bray
- Department of Psychology, University of Pennsylvania, Philadelphia, PA 19104
| | - Joel Bray
- Departments of Evolutionary Anthropology
| | - Lauren J N Brent
- Center for Cognitive Neuroscience,Duke Institute for Brain Sciences, Duke University, Durham, NC 27708
| | - Judith M Burkart
- Anthropological Institute and Museum, University of Zurich, 8057 Zurich, Switzerland
| | - Josep Call
- Department of Developmental and Comparative Psychology, Max Planck Institute for Evolutionary Anthropology, D-04103 Leipzig, Germany
| | | | - Lucy G Cheke
- Department of Psychology, University of Cambridge, Cambridge CB2 3EB, United Kingdom
| | - Nicola S Clayton
- Department of Psychology, University of Cambridge, Cambridge CB2 3EB, United Kingdom
| | | | - Louis J DiVincenti
- Department of Comparative Medicine, Seneca Park Zoo, University of Rochester, Rochester, NY 14620
| | - Kazuo Fujita
- Graduate School of Letters, Kyoto University, Kyoto 606-8501, Japan
| | - Esther Herrmann
- Department of Developmental and Comparative Psychology, Max Planck Institute for Evolutionary Anthropology, D-04103 Leipzig, Germany
| | | | - Lucia F Jacobs
- Department of Psychology andHelen Wills Neuroscience Institute, University of California, Berkeley, CA 94720
| | | | - Jennifer R Laude
- Department of Psychology, University of Kentucky, Lexington, KY 40506
| | | | - Emily J E Messer
- Department of Psychology and Neuroscience, University of St. Andrews, St. Andrews KY16 9JP, Scotland
| | - Antonio C de A Moura
- Departamento Engenharia e Meio Ambiente, Universidade Federal da Paraiba, 58059-900, João Pessoa, Brazil
| | - Ljerka Ostojić
- Department of Psychology, University of Cambridge, Cambridge CB2 3EB, United Kingdom
| | - Alejandra Picard
- Department of Psychology, University of York, Heslington, York YO10 5DD, United Kingdom
| | - Michael L Platt
- Departments of Evolutionary Anthropology,Center for Cognitive Neuroscience,Duke Institute for Brain Sciences, Duke University, Durham, NC 27708;Neurobiology, and
| | - Joshua M Plotnik
- Department of Psychology, University of Cambridge, Cambridge CB2 3EB, United Kingdom;Think Elephants International, Stone Ridge, NY 12484
| | - Friederike Range
- Messerli Research Institute, University of Veterinary Medicine Vienna, 1210 Vienna, Austria;Wolf Science Center, A-2115 Ernstbrunn, Austria
| | - Simon M Reader
- Department of Biology, McGill University, Montreal, QC, Canada H3A 1B1
| | - Rachna B Reddy
- Department of Anthropology, University of Michigan, Ann Arbor, MI 48109; and
| | - Aaron A Sandel
- Department of Anthropology, University of Michigan, Ann Arbor, MI 48109; and
| | - Laurie R Santos
- Department of Psychology, Yale University, New Haven, CT 06520
| | - Katrin Schumann
- Department of Developmental and Comparative Psychology, Max Planck Institute for Evolutionary Anthropology, D-04103 Leipzig, Germany
| | - Amanda M Seed
- Department of Psychology and Neuroscience, University of St. Andrews, St. Andrews KY16 9JP, Scotland
| | | | - Rachael C Shaw
- Department of Psychology, University of Cambridge, Cambridge CB2 3EB, United Kingdom
| | - Katie E Slocombe
- Department of Psychology, University of York, Heslington, York YO10 5DD, United Kingdom
| | - Yanjie Su
- Department of Psychology, Peking University, Beijing 100871, China
| | - Ayaka Takimoto
- Graduate School of Letters, Kyoto University, Kyoto 606-8501, Japan
| | | | - Ruoting Tao
- Department of Psychology and Neuroscience, University of St. Andrews, St. Andrews KY16 9JP, Scotland
| | - Carel P van Schaik
- Anthropological Institute and Museum, University of Zurich, 8057 Zurich, Switzerland
| | - Zsófia Virányi
- Messerli Research Institute, University of Veterinary Medicine Vienna, 1210 Vienna, Austria
| | - Elisabetta Visalberghi
- Istituto di Scienze e Tecnologie della Cognizione Consiglio Nazionale delle Ricerche, 00197 Rome, Italy
| | - Jordan C Wade
- Department of Psychology, University of Kentucky, Lexington, KY 40506
| | - Arii Watanabe
- Department of Psychology, University of Cambridge, Cambridge CB2 3EB, United Kingdom
| | - Jane Widness
- Department of Psychology, Yale University, New Haven, CT 06520
| | - Julie K Young
- Wildland Resources, Utah State University, Logan, UT 84322
| | - Thomas R Zentall
- Department of Psychology, University of Kentucky, Lexington, KY 40506
| | - Yini Zhao
- Department of Psychology, Peking University, Beijing 100871, China
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22
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Jiménez-Arenas JM, Pérez-Claros JA, Aledo JC, Palmqvist P. On the relationships of postcanine tooth size with dietary quality and brain volume in primates: implications for hominin evolution. BIOMED RESEARCH INTERNATIONAL 2014; 2014:406507. [PMID: 24592388 PMCID: PMC3925621 DOI: 10.1155/2014/406507] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/30/2013] [Revised: 12/15/2013] [Accepted: 12/16/2013] [Indexed: 11/17/2022]
Abstract
Brain volume and cheek-tooth size have traditionally been considered as two traits that show opposite evolutionary trends during the evolution of Homo. As a result, differences in encephalization and molarization among hominins tend to be interpreted in paleobiological grounds, because both traits were presumably linked to the dietary quality of extinct species. Here we show that there is an essential difference between the genus Homo and the living primate species, because postcanine tooth size and brain volume are related to negative allometry in primates and show an inverse relationship in Homo. However, when size effects are removed, the negative relationship between encephalization and molarization holds only for platyrrhines and the genus Homo. In addition, there is no general trend for the relationship between postcanine tooth size and dietary quality among the living primates. If size and phylogeny effects are both removed, this relationship vanishes in many taxonomic groups. As a result, the suggestion that the presence of well-developed postcanine teeth in extinct hominins should be indicative of a poor-quality diet cannot be generalized to all extant and extinct primates.
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Affiliation(s)
- Juan Manuel Jiménez-Arenas
- Departamento de Prehistoria y Arqueología, Facultad de Filosofía y Letras, Campus de Cartuja S/N, 18071 Granada, Spain ; Edificio Centro de Documentación Científica, Instituto Universitario de la Paz y los Conflictos, Universidad de Granada, C/Rector López Argüeta, 10871 Granada, Spain ; Anthropological Institute & Museum, University of Zürich, Winterthurerstrasse 190, 8057 Zürich, Switzerland
| | - Juan Antonio Pérez-Claros
- Departamento de Ecología y Geología (Área de Paleontología), Facultad de Ciencias, Campus Universitario de Teatinos, 29071 Málaga, Spain
| | - Juan Carlos Aledo
- Departamento de Biología Molecular y Bioquímica, Facultad de Ciencias, Campus Universitario de Teatinos, 29071 Málaga, Spain
| | - Paul Palmqvist
- Departamento de Ecología y Geología (Área de Paleontología), Facultad de Ciencias, Campus Universitario de Teatinos, 29071 Málaga, Spain
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23
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Modeling lineage and phenotypic diversification in the New World monkey (Platyrrhini, Primates) radiation. Mol Phylogenet Evol 2013; 82 Pt B:375-85. [PMID: 24287474 DOI: 10.1016/j.ympev.2013.11.008] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2012] [Revised: 10/24/2013] [Accepted: 11/15/2013] [Indexed: 11/19/2022]
Abstract
Adaptive radiations that have taken place in the distant past can now be more thoroughly studied with the availability of large molecular phylogenies and comparative data drawn from extant and fossil species. Platyrrhines are a good example of a major mammalian evolutionary radiation confined to a single continent, involving a relatively large temporal scale and documented by a relatively small but informative fossil record. Here, we present comparative evidence using data on extant and fossil species to explore alternative evolutionary models in an effort to better understand the process of platyrrhine lineage and phenotypic diversification. Specifically, we compare the likelihood of null models of lineage and phenotypic diversification versus various models of adaptive evolution. Moreover, we statistically explore the main ecological dimension behind the platyrrhine diversification. Contrary to the previous proposals, our study did not find evidence of a rapid lineage accumulation in the phylogenetic tree of extant platyrrhine species. However, the fossil-based diversity curve seems to show a slowdown in diversification rates toward present times. This also suggests an early high rate of extinction among lineages within crown Platyrrhini. Finally, our analyses support the hypothesis that the platyrrhine phenotypic diversification appears to be characterized by an early and profound differentiation in body size related to a multidimensional niche model, followed by little subsequent change (i.e., stasis).
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24
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Gonda A, Herczeg G, Merilä J. Evolutionary ecology of intraspecific brain size variation: a review. Ecol Evol 2013; 3:2751-64. [PMID: 24567837 PMCID: PMC3930043 DOI: 10.1002/ece3.627] [Citation(s) in RCA: 91] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2013] [Revised: 05/06/2013] [Accepted: 05/07/2013] [Indexed: 12/24/2022] Open
Abstract
The brain is a trait of central importance for organismal performance and fitness. To date, evolutionary studies of brain size variation have mainly utilized comparative methods applied at the level of species or higher taxa. However, these studies suffer from the difficulty of separating causality from correlation. In the other extreme, studies of brain plasticity have focused mainly on within-population patterns. Between these extremes lie interpopulational studies, focusing on brain size variation among populations of the same species that occupy different habitats or selective regimes. These studies form a rapidly growing field of investigations which can help us to understand brain evolution by providing a test bed for ideas born out of interspecific studies, as well as aid in uncovering the relative importance of genetic and environmental factors shaping variation in brain size and architecture. Aside from providing the first in depth review of published intraspecific studies of brain size variation, we discuss the prospects embedded with interpopulational studies of brain size variation. In particular, the following topics are identified as deserving further attention: (i) studies focusing on disentangling the contributions of genes, environment, and their interactions on brain variation within and among populations, (ii) studies applying quantitative genetic tools to evaluate the relative importance of genetic and environmental factors on brain features at different ontogenetic stages, (iii) apart from utilizing simple gross estimates of brain size, future studies could benefit from use of neuroanatomical, neurohistological, and/or molecular methods in characterizing variation in brain size and architecture. Evolution of brain size and architecture is a widely studied topic. However, the majority of studies are interspecific and comparative. Here we summarize the recently growing body of intraspecific studies based on population comparisons and outline the future potential in this approach.
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Affiliation(s)
- Abigél Gonda
- Ecological Genetics Research UnitDepartment of Biosciences, University of HelsinkiP.O. Box 65, FI-00014, Helsinki, Finland
| | - Gábor Herczeg
- Ecological Genetics Research UnitDepartment of Biosciences, University of HelsinkiP.O. Box 65, FI-00014, Helsinki, Finland
- Behavioural Ecology GroupDepartment of Systematic Zoology and Ecology, Eötvös Loránd UniversityPázmány Péter sétány 1/C, H-1117, Budapest, Hungary
| | - Juha Merilä
- Ecological Genetics Research UnitDepartment of Biosciences, University of HelsinkiP.O. Box 65, FI-00014, Helsinki, Finland
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25
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Sayers K. On folivory, competition, and intelligence: generalisms, overgeneralizations, and models of primate evolution. Primates 2013; 54:111-24. [PMID: 23263563 PMCID: PMC3644559 DOI: 10.1007/s10329-012-0335-1] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2012] [Accepted: 11/05/2012] [Indexed: 10/27/2022]
Abstract
Considerations of primate behavioral evolution often proceed by assuming the ecological and competitive milieus of particular taxa via their relative exploitation of gross food types, such as fruits versus leaves. Although this "fruit/leaf dichotomy" has been repeatedly criticized, it continues to be implicitly invoked in discussions of primate socioecology and female social relationships and is explicitly invoked in models of brain evolution. An expanding literature suggests that such views have severely limited our knowledge of the social and ecological complexities of primate folivory. This paper examines the behavior of primate folivore-frugivores, with particular emphasis on gray langurs (traditionally, Semnopithecus entellus) within the broader context of evolutionary ecology. Although possessing morphological characteristics that have been associated with folivory and constrained activity patterns, gray langurs are known for remarkable plasticity in ecology and behavior. Their diets are generally quite broad and can be discussed in relation to Liem's Paradox, the odd coupling of anatomical feeding specializations with a generalist foraging strategy. Gray langurs, not coincidentally, inhabit arguably the widest range of habitats for a nonhuman primate, including high elevations in the Himalayas. They provide an excellent focal point for examining the assumptions and predictions of behavioral, socioecological, and cognitive evolutionary models. Contrary to the classical descriptions of the primate folivore, Himalayan and other gray langurs-and, in actuality, many leaf-eating primates-range widely, engage in resource competition (both of which have previously been noted for primate folivores), and solve ecological problems rivaling those of more frugivorous primates (which has rarely been argued for primate folivores). It is maintained that questions of primate folivore adaptation, temperate primate adaptation, and primate evolution more generally cannot be answered by the frequent approach of broad characterizations, categorization models, crude variables, weakly correlative evidence, and subjective definitions. As a corollary, many current avenues of study are inadequate for explaining primate adaptation. A true understanding of primate ecology can only be achieved through the use of mainstream evolutionary ecology and thorough linkage of both proximate and ultimate mechanisms.
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Affiliation(s)
- Ken Sayers
- Language Research Center, Georgia State University, 3401 Panthersville Rd, Dectur, GA 30034, USA.
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