Ecological causes of fluctuating natural selection on habitat choice in an amphibian

Biased movement drives local cryptic coloration on distinct urban pavements

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2019.1343 ◽

2019 ◽

Vol 286 (1912) ◽

pp. 20191343 ◽

Cited By ~ 10

Author(s):

Pim Edelaar ◽

Adrian Baños-Villalba ◽

David P. Quevedo ◽

Graciela Escudero ◽

Daniel I. Bolnick ◽

...

Keyword(s):

Natural Selection ◽

Habitat Choice ◽

Mortality Rates ◽

Urban Environments ◽

Adaptive Plasticity ◽

Relative Importance ◽

Divergent Natural Selection ◽

Cryptic Coloration ◽

Selective Agents ◽

General Studies

Explanations of how organisms might adapt to urban environments have mostly focused on divergent natural selection and adaptive plasticity. However, differential habitat choice has been suggested as an alternative. Here, we test for habitat choice in enhancing crypsis in ground-perching grasshoppers colonizing an urbanized environment, composed of a mosaic of four distinctly coloured substrates (asphalt roads and adjacent pavements). Additionally, we determine its relative importance compared to present-day natural selection and phenotypic plasticity. We found that grasshoppers are very mobile, but nevertheless approximately match the colour of their local substrate. By manipulating grasshopper colour, we confirm that grasshoppers increase the usage of those urban substrates that resemble their own colours. This selective movement actively improves crypsis. Colour divergence between grasshoppers on different substrates is not or hardly owing to present-day natural selection, because observed mortality rates are too low to counteract random substrate use. Additional experiments also show negligible contributions from plasticity in colour. Our results confirm that matching habitat choice can be an important driver of adaptation to urban environments. In general, studies should more fully incorporate that individuals are not only selective targets (i.e. selected on by the environment), but also selective agents (i.e. selecting their own environments).

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Comparing the consequences of natural selection, adaptive phenotypic plasticity, and matching habitat choice for phenotype-environment matching, population genetic structure, and reproductive isolation in meta-populations

Ecology and Evolution ◽

10.1002/ece3.3816 ◽

2018 ◽

Vol 8 (8) ◽

pp. 3815-3827 ◽

Cited By ~ 19

Author(s):

Marion Nicolaus ◽

Pim Edelaar

Keyword(s):

Natural Selection ◽

Phenotypic Plasticity ◽

Genetic Structure ◽

Reproductive Isolation ◽

Population Genetic Structure ◽

Population Genetic ◽

Habitat Choice ◽

Adaptive Phenotypic Plasticity ◽

Matching Habitat Choice

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Sympatric speciation revealed by genome-wide divergence in the blind mole rat Spalax

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1514896112 ◽

2015 ◽

Vol 112 (38) ◽

pp. 11905-11910 ◽

Cited By ~ 24

Author(s):

Kexin Li ◽

Wei Hong ◽

Hengwu Jiao ◽

Guo-Dong Wang ◽

Karl A. Rodriguez ◽

...

Keyword(s):

Gene Flow ◽

Natural Selection ◽

Enrichment Analysis ◽

Habitat Choice ◽

Breeding Population ◽

Sympatric Speciation ◽

Population Divergence ◽

Genome Wide ◽

Population Structure Analysis ◽

Genome Analyses

Sympatric speciation (SS), i.e., speciation within a freely breeding population or in contiguous populations, was first proposed by Darwin [Darwin C (1859) On the Origins of Species by Means of Natural Selection] and is still controversial despite theoretical support [Gavrilets S (2004) Fitness Landscapes and the Origin of Species (MPB-41)] and mounting empirical evidence. Speciation of subterranean mammals generally, including the genus Spalax, was considered hitherto allopatric, whereby new species arise primarily through geographic isolation. Here we show in Spalax a case of genome-wide divergence analysis in mammals, demonstrating that SS in continuous populations, with gene flow, encompasses multiple widespread genomic adaptive complexes, associated with the sharply divergent ecologies. The two abutting soil populations of S. galili in northern Israel habituate the ancestral Senonian chalk population and abutting derivative Plio-Pleistocene basalt population. Population divergence originated ∼0.2–0.4 Mya based on both nuclear and mitochondrial genome analyses. Population structure analysis displayed two distinctly divergent clusters of chalk and basalt populations. Natural selection has acted on 300+ genes across the genome, diverging Spalax chalk and basalt soil populations. Gene ontology enrichment analysis highlights strong but differential soil population adaptive complexes: in basalt, sensory perception, musculature, metabolism, and energetics, and in chalk, nutrition and neurogenetics are outstanding. Population differentiation of chemoreceptor genes suggests intersoil population's mate and habitat choice substantiating SS. Importantly, distinctions in protein degradation may also contribute to SS. Natural selection and natural genetic engineering [Shapiro JA (2011) Evolution: A View From the 21st Century] overrule gene flow, evolving divergent ecological adaptive complexes. Sharp ecological divergences abound in nature; therefore, SS appears to be an important mode of speciation as first envisaged by Darwin [Darwin C (1859) On the Origins of Species by Means of Natural Selection].

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