1
|
Stratton JA, Nolte MJ, Payseur BA. Genetics of behavioural evolution in giant mice from Gough Island. Proc Biol Sci 2023; 290:20222603. [PMID: 37161324 PMCID: PMC10170209 DOI: 10.1098/rspb.2022.2603] [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: 12/30/2022] [Accepted: 04/14/2023] [Indexed: 05/11/2023] Open
Abstract
The evolution of behaviour on islands is a pervasive phenomenon that contributed to Darwin's theory of natural selection. Island populations frequently show increased boldness and exploration compared with their mainland counterparts. Despite the generality of this pattern, the genetic basis of island-associated behaviours remains a mystery. To address this gap in knowledge, we genetically dissected behaviour in 613 F2s generated by crossing inbred mouse strains from Gough Island (where they live without predators or human commensals) and a mainland conspecific. We used open field and light/dark box tests to measure seven behaviours related to boldness and exploration in juveniles and adults. Across all assays, we identified a total of 41 quantitative trait loci (QTL) influencing boldness and exploration. QTL have moderate effects and are often unique to specific behaviours or ages. Function-valued trait mapping revealed changes in estimated effects of QTL during assays, providing a rare dynamic window into the genetics of behaviour often missed by standard approaches. The genomic locations of QTL are distinct from those found in laboratory strains of mice, indicating different genetic paths to the evolution of similar behaviours. We combine our mapping results with extensive phenotypic and genetic information available for laboratory mice to nominate candidate genes for the evolution of behaviour on islands.
Collapse
Affiliation(s)
- Jered A. Stratton
- Laboratory of Genetics, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Mark J. Nolte
- Laboratory of Genetics, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Bret A. Payseur
- Laboratory of Genetics, University of Wisconsin-Madison, Madison, WI 53706, USA
| |
Collapse
|
2
|
Morris DW, Palmer S. Do animal personalities promote species coexistence? A test with sympatric boreal rodents. Ecology 2023; 104:e3913. [PMID: 36333888 DOI: 10.1002/ecy.3913] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/15/2021] [Revised: 09/06/2022] [Accepted: 09/19/2022] [Indexed: 11/06/2022]
Abstract
The coexistence of competing species requires density feedbacks that have a larger effect on their own species' population growth than they do on others in the assembly. The feedbacks are often associated with behavioral tradeoffs that enable species to differentially exploit underlying axes of heterogeneity. Conjoining theories of species coexistence with foraging behavior and density-dependent habitat selection reveals that such tradeoffs impinge on invasion probabilities and equilibrium dynamics emerging from species' differences in habitat use. The resulting habitat separation promotes coexistence by reducing the overall interaction among species. Differential habitat selection depends on the behavioral abilities of organisms to identify and exploit the most profitable habitats and resource patches. One might thus expect that each species will evolve behavioral types distinct from those of other potential competitors. Accordingly, we exposed four coexisting species in four genera of boreal rodents to open-field tests. We used principal components (PC) to summarize their behaviors along three independent axes corresponding with clines of exploratory, vigilant, and apprehensive personalities. We confirmed that the axes represented repeatable behaviors (personalities) and assessed differences among species with a general linear model (GLM). The GLM revealed highly distinct differences among species, and between pairs of species, on each PC. Even so, it is difficult to infer the adaptive advantages of personality to the habitat segregation that reduces otherwise high interactions among species. Rather, personalities are best interpreted as co-adaptive behaviors reflecting the complex of morphological, physiological and behavioral attributes that dictate tradeoffs and enable coexistence.
Collapse
Affiliation(s)
- Douglas W Morris
- Department of Biology, Lakehead University, Thunder Bay, Ontario, Canada
| | - Sommer Palmer
- Department of Biology, Lakehead University, Thunder Bay, Ontario, Canada
| |
Collapse
|
3
|
Cossette ML, Stewart DT, Haghani A, Zoller JA, Shafer ABA, Horvath S. Epigenetics and island-mainland divergence in an insectivorous small mammal. Mol Ecol 2023; 32:152-166. [PMID: 36226847 DOI: 10.1111/mec.16735] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2022] [Revised: 09/20/2022] [Accepted: 09/28/2022] [Indexed: 12/29/2022]
Abstract
Geographically isolated populations, specifically island-mainland counterparts, tend to exhibit phenotypic variation in many species. The so-called island syndrome occurs when different environmental pressures lead to insular divergence from mainland populations. This phenomenon can be seen in an island population of Nova Scotia masked shrews (Sorex cinereus), which have developed a specialized feeding habit and digestive enzyme compared to their mainland counterparts. Epigenetic modifications, such as DNA methylation (DNAm), can impact phenotypes by altering gene expression without changing the DNA sequence. Here, we used a de novo masked shrew genome assembly and a mammalian methylation array profiling 37 thousand conserved CpGs to investigate morphological and DNA methylation patterns between island and mainland populations. Island shrews were morphologically and epigenetically different than their mainland counterparts, exhibiting a smaller body size. A gene ontology enrichment analyses of differentially methylated CpGs implicated developmental and digestive system related pathways. Based on our shrew epigenetic clock, island shrews might also be aging faster than their mainland counterparts. This study provides novel insight on phenotypic and epigenetic divergence in island-mainland mammal populations and suggests an underlying role of methylation in island-mainland divergence.
Collapse
Affiliation(s)
- Marie-Laurence Cossette
- Department of Environmental Life Sciences Graduate Program, Trent University, Peterborough, Ontario, Canada
| | - Donald T Stewart
- Department of Biology, Acadia University, Wolfville, Nova Scotia, Canada
| | - Amin Haghani
- Department of Human Genetics, David Geffen School of Medicine, University of California, Los Angeles, California, USA
| | - Joseph A Zoller
- Department of Biostatistics, Fielding School of Public Health, University of California, Los Angeles, California, USA
| | - Aaron B A Shafer
- Department of Environmental Life Sciences Graduate Program, Trent University, Peterborough, Ontario, Canada
- Department of Forensic Science, Trent University, Peterborough, Ontario, Canada
| | - Steve Horvath
- Department of Human Genetics, David Geffen School of Medicine, University of California, Los Angeles, California, USA
- Department of Biostatistics, Fielding School of Public Health, University of California, Los Angeles, California, USA
- Altos Labs, San Diego, California, USA
| |
Collapse
|
4
|
Gavriilidi I, De Meester G, Van Damme R, Baeckens S. How to behave when marooned: the behavioural component of the island syndrome remains underexplored. Biol Lett 2022; 18:20220030. [PMID: 35440235 PMCID: PMC9039784 DOI: 10.1098/rsbl.2022.0030] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2022] [Accepted: 03/25/2022] [Indexed: 12/16/2022] Open
Abstract
Animals on islands typically depart from their mainland relatives in assorted aspects of their biology. Because they seem to occur in concert, and to some extent evolve convergently in disparate taxa, these changes are referred to as the 'island syndrome'. While morphological, physiological and life-history components of the island syndrome have received considerable attention, much less is known about how insularity affects behaviour. In this paper, we argue why changes in personality traits and cognitive abilities can be expected to form part of the island syndrome. We provide an overview of studies that have compared personality traits and cognitive abilities between island and mainland populations, or among islands. Overall, the pickings are remarkably slim. There is evidence that animals on islands tend to be bolder than on the mainland, but effects on other personality traits go either way. The evidence for effects of insularity on cognitive abilities or style is highly circumstantial and very mixed. Finally, we consider the ecological drivers that may induce such changes, and the mechanisms through which they might occur. We conclude that our knowledge of the behavioural and cognitive responses to island environments remains limited, and we encourage behavioural biologists to make more use of these 'natural laboratories for evolution'.
Collapse
Affiliation(s)
- Ioanna Gavriilidi
- Functional Morphology Lab, Department of Biology, University of Antwerp, Wilrijk, Belgium
- Section of Zoology and Marine Biology, Department of Biology, National and Kapodistrian University of Athens, Greece
| | - Gilles De Meester
- Functional Morphology Lab, Department of Biology, University of Antwerp, Wilrijk, Belgium
| | - Raoul Van Damme
- Functional Morphology Lab, Department of Biology, University of Antwerp, Wilrijk, Belgium
| | - Simon Baeckens
- Functional Morphology Lab, Department of Biology, University of Antwerp, Wilrijk, Belgium
- Evolution and Optics of Nanostructures Lab, Department of Biology, Ghent University, Ghent, Belgium
| |
Collapse
|
5
|
Sinnott‐Armstrong MA, Deanna R, Pretz C, Liu S, Harris JC, Dunbar‐Wallis A, Smith SD, Wheeler LC. How to approach the study of syndromes in macroevolution and ecology. Ecol Evol 2022; 12:e8583. [PMID: 35342598 PMCID: PMC8928880 DOI: 10.1002/ece3.8583] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2021] [Revised: 12/23/2021] [Accepted: 12/31/2021] [Indexed: 11/12/2022] Open
Abstract
Syndromes, wherein multiple traits evolve convergently in response to a shared selective driver, form a central concept in ecology and evolution. Recent work has questioned the existence of some classic syndromes, such as pollination and seed dispersal syndromes. Here, we discuss some of the major issues that have afflicted research into syndromes in macroevolution and ecology. First, correlated evolution of traits and hypothesized selective drivers is often relied on as the only evidence for adaptation of those traits to those hypothesized drivers, without supporting evidence. Second, the selective driver is often inferred from a combination of traits without explicit testing. Third, researchers often measure traits that are easy for humans to observe rather than measuring traits that are suited to testing the hypothesis of adaptation. Finally, species are often chosen for study because of their striking phenotypes, which leads to the illusion of syndromes and divergence. We argue that these issues can be avoided by combining studies of trait variation across entire clades or communities with explicit tests of adaptive hypotheses and that taking this approach will lead to a better understanding of syndrome-like evolution and its drivers.
Collapse
Affiliation(s)
- Miranda A. Sinnott‐Armstrong
- Department of Ecology and Evolutionary BiologyUniversity of Colorado‐BoulderBoulderColoradoUSA
- Department of ChemistryUniversity of CambridgeCambridgeUK
| | - Rocio Deanna
- Department of Ecology and Evolutionary BiologyUniversity of Colorado‐BoulderBoulderColoradoUSA
- Instituto Multidisciplinario de Biología VegetalIMBIV (CONICET‐UNC)CórdobaArgentina
- Departamento de Ciencias FarmacéuticasFacultad de Ciencias Químicas (FCQ, UNC)CórdobaArgentina
| | - Chelsea Pretz
- Department of Ecology and Evolutionary BiologyUniversity of Colorado‐BoulderBoulderColoradoUSA
| | - Sukuan Liu
- Department of Ecology and Evolutionary BiologyUniversity of Colorado‐BoulderBoulderColoradoUSA
| | - Jesse C. Harris
- Department of Ecology and Evolutionary BiologyUniversity of Colorado‐BoulderBoulderColoradoUSA
| | - Amy Dunbar‐Wallis
- Department of Ecology and Evolutionary BiologyUniversity of Colorado‐BoulderBoulderColoradoUSA
| | - Stacey D. Smith
- Department of Ecology and Evolutionary BiologyUniversity of Colorado‐BoulderBoulderColoradoUSA
| | - Lucas C. Wheeler
- Department of Ecology and Evolutionary BiologyUniversity of Colorado‐BoulderBoulderColoradoUSA
| |
Collapse
|
6
|
Linking genetic, morphological, and behavioural divergence between inland island and mainland deer mice. Heredity (Edinb) 2022; 128:97-106. [PMID: 34952930 PMCID: PMC8814197 DOI: 10.1038/s41437-021-00492-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2021] [Revised: 12/09/2021] [Accepted: 12/10/2021] [Indexed: 02/03/2023] Open
Abstract
The island syndrome hypothesis (ISH) stipulates that, as a result of local selection pressures and restricted gene flow, individuals from island populations should differ from individuals within mainland populations. Specifically, island populations are predicted to contain individuals that are larger, less aggressive, more sociable, and that invest more in their offspring. To date, tests of the ISH have mainly compared oceanic islands to continental sites, and rarely smaller spatial scales such as inland watersheds. Here, using a novel set of genome-wide SNP markers in wild deer mice (Peromyscus maniculatus) we conducted a genomic assessment of predictions underlying the ISH in an inland riverine island system: analysing island-mainland population structure, and quantifying heritability of phenotypes thought to underlie the ISH. We found clear genomic differentiation between the island and mainland populations and moderate to high marker-based heritability estimates for overall variation in traits previously found to differ in line with the ISH between mainland and island locations. FST outlier analyses highlighted 12 loci associated with differentiation between mainland and island populations. Together these results suggest that the island populations examined are on independent evolutionary trajectories, the traits considered have a genetic basis (rather than phenotypic variation being solely due to phenotypic plasticity). Coupled with the previous results showing significant phenotypic differentiation between the island and mainland groups in this system, this study suggests that the ISH can hold even on a small spatial scale.
Collapse
|