Unprecedented Biting Performance in Herbivorous Fish: How the Complex Biting System of Pomacentridae Circumvents Performance Trade-Offs
Am Nat. 2021 May;197(5):E156-E172. doi: 10.1086/713498. Epub 2021 Mar 19.ABSTRACTAbstractIt is well accepted that the complexity of functional systems may mitigate performance trade-offs. However, data supporting this theory are hard to find because they need to be based on a functional system with different complexity levels in closely related species. The Pomacentridae (damselfishes) provide an excellent opportunity to test this hypothesis because most of the species have two mouth-closing systems: the first using the adductor mandibulae, as in all teleost fishes, and the second relying on the ceratomandibular (cmd) liga...
Source: The American Naturalist - April 28, 2021 Category: Biology Authors: Damien Olivier Sam Van Wassenbergh Eric Parmentier Bruno Fr édérich Source Type: research

Accelerated Brain Shape Evolution Is Associated with Rapid Diversification in an Avian Radiation
Am Nat. 2021 May;197(5):576-591. doi: 10.1086/713664. Epub 2021 Mar 22.ABSTRACTAbstractNiche expansion is a critical step in the speciation process. Large brains linked to improved cognitive ability may enable species to expand their niches and forage in new ways, thereby promoting speciation. Despite considerable work on ecological divergence in brain size and its importance in speciation, relatively little is known about how brain shape relates to behavioral, ecological, and taxonomic diversity at macroevolutionary scales. This is due in part to inherent challenges with quantifying brain shape across many species. Here w...
Source: The American Naturalist - April 28, 2021 Category: Biology Authors: Chad M Eliason Jenna M McCullough Michael J Andersen Shannon J Hackett Source Type: research

On Deleterious Mutations in Perennials: Inbreeding Depression, Mutation Load, and Life-History Evolution
In this study, we investigate this hypothesis. We combine a physiological growth model and multilocus population genetics approaches to describe a full genotype-to-phenotype-to-fitness map. We study the behavior of mutations affecting growth or survival and explore their consequences in terms of inbreeding depression and mutation load. Although our results agree with empirical data only within a narrow range of conditions, we argue that they may point us toward the type of traits capable of generating high inbreeding depression in long-lived species-that is, traits under sufficiently strong selection, on which selection de...
Source: The American Naturalist - April 28, 2021 Category: Biology Authors: Thomas Lesaffre Sylvain Billiard Source Type: research

The Allometry of Sound Frequency Bandwidth in Songbirds
Am Nat. 2021 May;197(5):607-614. doi: 10.1086/713708. Epub 2021 Mar 11.ABSTRACTAbstractTheory predicts that allometric constraints on sound production should be stronger for the lower frequencies of vocalizations than for the higher frequencies, which could originate from an allometry for sound frequency bandwidth. Using song recordings of approximately 1,000 passerine species (from>75% passerine genera), we show a significantly steeper allometry for the lower song frequencies than for the higher song frequencies, resulting in a positive allometry of frequency bandwidth: larger species can use wider bandwidths than smal...
Source: The American Naturalist - April 28, 2021 Category: Biology Authors: Jakob Isager Friis Joana Sabino Pedro Santos Torben Dabelsteen Gon çalo C Cardoso Source Type: research

Rethinking Gloger's Rule: Climate, Light Environments, and Color in a Large Family of Tropical Birds (Furnariidae)
Am Nat. 2021 May;197(5):592-606. doi: 10.1086/713386. Epub 2021 Mar 23.ABSTRACTAbstractEcogeographic rules provide a framework within which to test evolutionary hypotheses of adaptation. Gloger's rule predicts that endothermic animals should have darker colors in warm/rainy climates. This rule also predicts that animals should be more rufous in warm/dry climates, the so-called complex Gloger's rule. Empirical studies frequently demonstrate that animals are darker in cool/wet climates rather than in warm/wet climates. Furthermore, sensory ecology predicts that, to enhance crypsis, animals should be darker in darker light en...
Source: The American Naturalist - April 28, 2021 Category: Biology Authors: Rafael S Marcondes Jonathan A Nations Glenn F Seeholzer Robb T Brumfield Source Type: research

The Evolution of Social Dominance through Reinforcement Learning
Am Nat. 2021 May;197(5):560-575. doi: 10.1086/713758. Epub 2021 Mar 30.ABSTRACTAbstractGroups of social animals are often organized into dominance hierarchies that are formed through pairwise interactions. There is much experimental data on hierarchies, examining such things as winner, loser, and bystander effects, as well as the linearity and replicability of hierarchies, but there is a lack evolutionary analyses of these basic observations. Here I present a game theory model of hierarchy formation in which individuals adjust their aggressive behavior toward other group members through reinforcement learning. Individual t...
Source: The American Naturalist - April 28, 2021 Category: Biology Authors: Olof Leimar Source Type: research

Dispersal Alters the Nature and Scope of Sexually Antagonistic Variation
Am Nat. 2021 May;197(5):543-559. doi: 10.1086/713739. Epub 2021 Apr 7.ABSTRACTAbstractIntralocus sexual conflict, or sexual antagonism, occurs when alleles have opposing fitness effects in the two sexes. Previous theory suggests that sexual antagonism is a driver of genetic variation by generating balancing selection. However, most of these studies assume that populations are well mixed, neglecting the effects of spatial subdivision. Here, we use mathematical modeling to show that limited dispersal changes evolution at sexually antagonistic autosomal and X-linked loci as a result of inbreeding and sex-specific kin competit...
Source: The American Naturalist - April 28, 2021 Category: Biology Authors: Ewan O Flintham Vincent Savolainen Charles Mullon Source Type: research

Density-Dependent and Species-Specific Effects on Self-Organization Modulate the Resistance of Mussel Bed Ecosystems to Hydrodynamic Stress
Am Nat. 2021 May;197(5):615-623. doi: 10.1086/713738. Epub 2021 Mar 24.ABSTRACTAbstractSelf-organized, regular spatial patterns emerging from local interactions among individuals enhance the ability of ecosystems to respond to environmental disturbances. Mussels self-organize to form large, regularly patterned biogenic structures that modify the biotic and abiotic environment and provide numerous ecosystem functions and services. We used two mussel species that form monospecific and mixed beds to investigate how species-specific behavior affects self-organization and resistance to wave stress. Perna perna has strong attach...
Source: The American Naturalist - April 28, 2021 Category: Biology Authors: Gerardo I Zardi Katy R Nicastro Christopher D McQuaid Monique de Jager Johan van de Koppel Laurent Seuront Source Type: research

The Genetic Architecture of Fitness Drives Population Viability during Rapid Environmental Change
Am Nat. 2021 May;197(5):511-525. doi: 10.1086/713469. Epub 2021 Mar 22.ABSTRACTAbstractThe rapid global loss of biodiversity calls for improved predictions of how populations will evolve and respond demographically to ongoing environmental change. The heritability (h2) of selected traits has long been known to affect evolutionary and demographic responses to environmental change. However, effects of the genetic architecture underlying the h2 of a selected trait on population responses to selection are less well understood. We use deterministic models and stochastic simulations to show that the genetic architecture underlyi...
Source: The American Naturalist - April 28, 2021 Category: Biology Authors: Marty Kardos Gordon Luikart Source Type: research

The Effect of the Recombination Rate between Adaptive Loci on the Capacity of a Population to Expand Its Range
Am Nat. 2021 May;197(5):526-542. doi: 10.1086/713669. Epub 2021 Apr 8.ABSTRACTAbstractPrevious theoretical work on range expansions over heterogeneous environments showed that there is a critical environmental gradient where range expansion stops. For populations with freely recombining loci underlying the trait under selection (hereafter, "adaptive loci"), the critical gradient in one-dimensional habitats depends on the fitness cost of dispersal and the strength of selection relative to genetic drift. Here, we extend the previous work in two directions and ask, What is the role of the recombination rate between ...
Source: The American Naturalist - April 28, 2021 Category: Biology Authors: Martin Eriksson Marina Rafajlovi ć Source Type: research

Correction
Am Nat. 2021 May;197(5):624. doi: 10.1086/713711. Epub 2021 Mar 18.NO ABSTRACTPMID:33908833 | DOI:10.1086/713711 (Source: The American Naturalist)
Source: The American Naturalist - April 28, 2021 Category: Biology Authors: Benjamin G Freeman Micah N Scholer Mannfred M A Boehm Julian Heavyside Dolph Schluter Source Type: research

Unprecedented Biting Performance in Herbivorous Fish: How the Complex Biting System of Pomacentridae Circumvents Performance Trade-Offs
Am Nat. 2021 May;197(5):E156-E172. doi: 10.1086/713498. Epub 2021 Mar 19.ABSTRACTAbstractIt is well accepted that the complexity of functional systems may mitigate performance trade-offs. However, data supporting this theory are hard to find because they need to be based on a functional system with different complexity levels in closely related species. The Pomacentridae (damselfishes) provide an excellent opportunity to test this hypothesis because most of the species have two mouth-closing systems: the first using the adductor mandibulae, as in all teleost fishes, and the second relying on the ceratomandibular (cmd) liga...
Source: The American Naturalist - April 28, 2021 Category: Biology Authors: Damien Olivier Sam Van Wassenbergh Eric Parmentier Bruno Fr édérich Source Type: research

Accelerated Brain Shape Evolution Is Associated with Rapid Diversification in an Avian Radiation
Am Nat. 2021 May;197(5):576-591. doi: 10.1086/713664. Epub 2021 Mar 22.ABSTRACTAbstractNiche expansion is a critical step in the speciation process. Large brains linked to improved cognitive ability may enable species to expand their niches and forage in new ways, thereby promoting speciation. Despite considerable work on ecological divergence in brain size and its importance in speciation, relatively little is known about how brain shape relates to behavioral, ecological, and taxonomic diversity at macroevolutionary scales. This is due in part to inherent challenges with quantifying brain shape across many species. Here w...
Source: The American Naturalist - April 28, 2021 Category: Biology Authors: Chad M Eliason Jenna M McCullough Michael J Andersen Shannon J Hackett Source Type: research

On Deleterious Mutations in Perennials: Inbreeding Depression, Mutation Load, and Life-History Evolution
In this study, we investigate this hypothesis. We combine a physiological growth model and multilocus population genetics approaches to describe a full genotype-to-phenotype-to-fitness map. We study the behavior of mutations affecting growth or survival and explore their consequences in terms of inbreeding depression and mutation load. Although our results agree with empirical data only within a narrow range of conditions, we argue that they may point us toward the type of traits capable of generating high inbreeding depression in long-lived species-that is, traits under sufficiently strong selection, on which selection de...
Source: The American Naturalist - April 28, 2021 Category: Biology Authors: Thomas Lesaffre Sylvain Billiard Source Type: research

The Allometry of Sound Frequency Bandwidth in Songbirds
Am Nat. 2021 May;197(5):607-614. doi: 10.1086/713708. Epub 2021 Mar 11.ABSTRACTAbstractTheory predicts that allometric constraints on sound production should be stronger for the lower frequencies of vocalizations than for the higher frequencies, which could originate from an allometry for sound frequency bandwidth. Using song recordings of approximately 1,000 passerine species (from>75% passerine genera), we show a significantly steeper allometry for the lower song frequencies than for the higher song frequencies, resulting in a positive allometry of frequency bandwidth: larger species can use wider bandwidths than smal...
Source: The American Naturalist - April 28, 2021 Category: Biology Authors: Jakob Isager Friis Joana Sabino Pedro Santos Torben Dabelsteen Gon çalo C Cardoso Source Type: research

Rethinking Gloger's Rule: Climate, Light Environments, and Color in a Large Family of Tropical Birds (Furnariidae)
Am Nat. 2021 May;197(5):592-606. doi: 10.1086/713386. Epub 2021 Mar 23.ABSTRACTAbstractEcogeographic rules provide a framework within which to test evolutionary hypotheses of adaptation. Gloger's rule predicts that endothermic animals should have darker colors in warm/rainy climates. This rule also predicts that animals should be more rufous in warm/dry climates, the so-called complex Gloger's rule. Empirical studies frequently demonstrate that animals are darker in cool/wet climates rather than in warm/wet climates. Furthermore, sensory ecology predicts that, to enhance crypsis, animals should be darker in darker light en...
Source: The American Naturalist - April 28, 2021 Category: Biology Authors: Rafael S Marcondes Jonathan A Nations Glenn F Seeholzer Robb T Brumfield Source Type: research

The Evolution of Social Dominance through Reinforcement Learning
Am Nat. 2021 May;197(5):560-575. doi: 10.1086/713758. Epub 2021 Mar 30.ABSTRACTAbstractGroups of social animals are often organized into dominance hierarchies that are formed through pairwise interactions. There is much experimental data on hierarchies, examining such things as winner, loser, and bystander effects, as well as the linearity and replicability of hierarchies, but there is a lack evolutionary analyses of these basic observations. Here I present a game theory model of hierarchy formation in which individuals adjust their aggressive behavior toward other group members through reinforcement learning. Individual t...
Source: The American Naturalist - April 28, 2021 Category: Biology Authors: Olof Leimar Source Type: research

Dispersal Alters the Nature and Scope of Sexually Antagonistic Variation
Am Nat. 2021 May;197(5):543-559. doi: 10.1086/713739. Epub 2021 Apr 7.ABSTRACTAbstractIntralocus sexual conflict, or sexual antagonism, occurs when alleles have opposing fitness effects in the two sexes. Previous theory suggests that sexual antagonism is a driver of genetic variation by generating balancing selection. However, most of these studies assume that populations are well mixed, neglecting the effects of spatial subdivision. Here, we use mathematical modeling to show that limited dispersal changes evolution at sexually antagonistic autosomal and X-linked loci as a result of inbreeding and sex-specific kin competit...
Source: The American Naturalist - April 28, 2021 Category: Biology Authors: Ewan O Flintham Vincent Savolainen Charles Mullon Source Type: research

Density-Dependent and Species-Specific Effects on Self-Organization Modulate the Resistance of Mussel Bed Ecosystems to Hydrodynamic Stress
Am Nat. 2021 May;197(5):615-623. doi: 10.1086/713738. Epub 2021 Mar 24.ABSTRACTAbstractSelf-organized, regular spatial patterns emerging from local interactions among individuals enhance the ability of ecosystems to respond to environmental disturbances. Mussels self-organize to form large, regularly patterned biogenic structures that modify the biotic and abiotic environment and provide numerous ecosystem functions and services. We used two mussel species that form monospecific and mixed beds to investigate how species-specific behavior affects self-organization and resistance to wave stress. Perna perna has strong attach...
Source: The American Naturalist - April 28, 2021 Category: Biology Authors: Gerardo I Zardi Katy R Nicastro Christopher D McQuaid Monique de Jager Johan van de Koppel Laurent Seuront Source Type: research

The Genetic Architecture of Fitness Drives Population Viability during Rapid Environmental Change
Am Nat. 2021 May;197(5):511-525. doi: 10.1086/713469. Epub 2021 Mar 22.ABSTRACTAbstractThe rapid global loss of biodiversity calls for improved predictions of how populations will evolve and respond demographically to ongoing environmental change. The heritability (h2) of selected traits has long been known to affect evolutionary and demographic responses to environmental change. However, effects of the genetic architecture underlying the h2 of a selected trait on population responses to selection are less well understood. We use deterministic models and stochastic simulations to show that the genetic architecture underlyi...
Source: The American Naturalist - April 28, 2021 Category: Biology Authors: Marty Kardos Gordon Luikart Source Type: research

The Effect of the Recombination Rate between Adaptive Loci on the Capacity of a Population to Expand Its Range
Am Nat. 2021 May;197(5):526-542. doi: 10.1086/713669. Epub 2021 Apr 8.ABSTRACTAbstractPrevious theoretical work on range expansions over heterogeneous environments showed that there is a critical environmental gradient where range expansion stops. For populations with freely recombining loci underlying the trait under selection (hereafter, "adaptive loci"), the critical gradient in one-dimensional habitats depends on the fitness cost of dispersal and the strength of selection relative to genetic drift. Here, we extend the previous work in two directions and ask, What is the role of the recombination rate between ...
Source: The American Naturalist - April 28, 2021 Category: Biology Authors: Martin Eriksson Marina Rafajlovi ć Source Type: research

Correction
Am Nat. 2021 May;197(5):624. doi: 10.1086/713711. Epub 2021 Mar 18.NO ABSTRACTPMID:33908833 | DOI:10.1086/713711 (Source: The American Naturalist)
Source: The American Naturalist - April 28, 2021 Category: Biology Authors: Benjamin G Freeman Micah N Scholer Mannfred M A Boehm Julian Heavyside Dolph Schluter Source Type: research

Unprecedented Biting Performance in Herbivorous Fish: How the Complex Biting System of Pomacentridae Circumvents Performance Trade-Offs
Am Nat. 2021 May;197(5):E156-E172. doi: 10.1086/713498. Epub 2021 Mar 19.ABSTRACTAbstractIt is well accepted that the complexity of functional systems may mitigate performance trade-offs. However, data supporting this theory are hard to find because they need to be based on a functional system with different complexity levels in closely related species. The Pomacentridae (damselfishes) provide an excellent opportunity to test this hypothesis because most of the species have two mouth-closing systems: the first using the adductor mandibulae, as in all teleost fishes, and the second relying on the ceratomandibular (cmd) liga...
Source: The American Naturalist - April 28, 2021 Category: Biology Authors: Damien Olivier Sam Van Wassenbergh Eric Parmentier Bruno Fr édérich Source Type: research

Accelerated Brain Shape Evolution Is Associated with Rapid Diversification in an Avian Radiation
Am Nat. 2021 May;197(5):576-591. doi: 10.1086/713664. Epub 2021 Mar 22.ABSTRACTAbstractNiche expansion is a critical step in the speciation process. Large brains linked to improved cognitive ability may enable species to expand their niches and forage in new ways, thereby promoting speciation. Despite considerable work on ecological divergence in brain size and its importance in speciation, relatively little is known about how brain shape relates to behavioral, ecological, and taxonomic diversity at macroevolutionary scales. This is due in part to inherent challenges with quantifying brain shape across many species. Here w...
Source: The American Naturalist - April 28, 2021 Category: Biology Authors: Chad M Eliason Jenna M McCullough Michael J Andersen Shannon J Hackett Source Type: research

On Deleterious Mutations in Perennials: Inbreeding Depression, Mutation Load, and Life-History Evolution
In this study, we investigate this hypothesis. We combine a physiological growth model and multilocus population genetics approaches to describe a full genotype-to-phenotype-to-fitness map. We study the behavior of mutations affecting growth or survival and explore their consequences in terms of inbreeding depression and mutation load. Although our results agree with empirical data only within a narrow range of conditions, we argue that they may point us toward the type of traits capable of generating high inbreeding depression in long-lived species-that is, traits under sufficiently strong selection, on which selection de...
Source: The American Naturalist - April 28, 2021 Category: Biology Authors: Thomas Lesaffre Sylvain Billiard Source Type: research

The Allometry of Sound Frequency Bandwidth in Songbirds
Am Nat. 2021 May;197(5):607-614. doi: 10.1086/713708. Epub 2021 Mar 11.ABSTRACTAbstractTheory predicts that allometric constraints on sound production should be stronger for the lower frequencies of vocalizations than for the higher frequencies, which could originate from an allometry for sound frequency bandwidth. Using song recordings of approximately 1,000 passerine species (from>75% passerine genera), we show a significantly steeper allometry for the lower song frequencies than for the higher song frequencies, resulting in a positive allometry of frequency bandwidth: larger species can use wider bandwidths than smal...
Source: The American Naturalist - April 28, 2021 Category: Biology Authors: Jakob Isager Friis Joana Sabino Pedro Santos Torben Dabelsteen Gon çalo C Cardoso Source Type: research

Rethinking Gloger's Rule: Climate, Light Environments, and Color in a Large Family of Tropical Birds (Furnariidae)
Am Nat. 2021 May;197(5):592-606. doi: 10.1086/713386. Epub 2021 Mar 23.ABSTRACTAbstractEcogeographic rules provide a framework within which to test evolutionary hypotheses of adaptation. Gloger's rule predicts that endothermic animals should have darker colors in warm/rainy climates. This rule also predicts that animals should be more rufous in warm/dry climates, the so-called complex Gloger's rule. Empirical studies frequently demonstrate that animals are darker in cool/wet climates rather than in warm/wet climates. Furthermore, sensory ecology predicts that, to enhance crypsis, animals should be darker in darker light en...
Source: The American Naturalist - April 28, 2021 Category: Biology Authors: Rafael S Marcondes Jonathan A Nations Glenn F Seeholzer Robb T Brumfield Source Type: research

The Evolution of Social Dominance through Reinforcement Learning
Am Nat. 2021 May;197(5):560-575. doi: 10.1086/713758. Epub 2021 Mar 30.ABSTRACTAbstractGroups of social animals are often organized into dominance hierarchies that are formed through pairwise interactions. There is much experimental data on hierarchies, examining such things as winner, loser, and bystander effects, as well as the linearity and replicability of hierarchies, but there is a lack evolutionary analyses of these basic observations. Here I present a game theory model of hierarchy formation in which individuals adjust their aggressive behavior toward other group members through reinforcement learning. Individual t...
Source: The American Naturalist - April 28, 2021 Category: Biology Authors: Olof Leimar Source Type: research

Dispersal Alters the Nature and Scope of Sexually Antagonistic Variation
Am Nat. 2021 May;197(5):543-559. doi: 10.1086/713739. Epub 2021 Apr 7.ABSTRACTAbstractIntralocus sexual conflict, or sexual antagonism, occurs when alleles have opposing fitness effects in the two sexes. Previous theory suggests that sexual antagonism is a driver of genetic variation by generating balancing selection. However, most of these studies assume that populations are well mixed, neglecting the effects of spatial subdivision. Here, we use mathematical modeling to show that limited dispersal changes evolution at sexually antagonistic autosomal and X-linked loci as a result of inbreeding and sex-specific kin competit...
Source: The American Naturalist - April 28, 2021 Category: Biology Authors: Ewan O Flintham Vincent Savolainen Charles Mullon Source Type: research

Density-Dependent and Species-Specific Effects on Self-Organization Modulate the Resistance of Mussel Bed Ecosystems to Hydrodynamic Stress
Am Nat. 2021 May;197(5):615-623. doi: 10.1086/713738. Epub 2021 Mar 24.ABSTRACTAbstractSelf-organized, regular spatial patterns emerging from local interactions among individuals enhance the ability of ecosystems to respond to environmental disturbances. Mussels self-organize to form large, regularly patterned biogenic structures that modify the biotic and abiotic environment and provide numerous ecosystem functions and services. We used two mussel species that form monospecific and mixed beds to investigate how species-specific behavior affects self-organization and resistance to wave stress. Perna perna has strong attach...
Source: The American Naturalist - April 28, 2021 Category: Biology Authors: Gerardo I Zardi Katy R Nicastro Christopher D McQuaid Monique de Jager Johan van de Koppel Laurent Seuront Source Type: research

The Genetic Architecture of Fitness Drives Population Viability during Rapid Environmental Change
Am Nat. 2021 May;197(5):511-525. doi: 10.1086/713469. Epub 2021 Mar 22.ABSTRACTAbstractThe rapid global loss of biodiversity calls for improved predictions of how populations will evolve and respond demographically to ongoing environmental change. The heritability (h2) of selected traits has long been known to affect evolutionary and demographic responses to environmental change. However, effects of the genetic architecture underlying the h2 of a selected trait on population responses to selection are less well understood. We use deterministic models and stochastic simulations to show that the genetic architecture underlyi...
Source: The American Naturalist - April 28, 2021 Category: Biology Authors: Marty Kardos Gordon Luikart Source Type: research

The Effect of the Recombination Rate between Adaptive Loci on the Capacity of a Population to Expand Its Range
Am Nat. 2021 May;197(5):526-542. doi: 10.1086/713669. Epub 2021 Apr 8.ABSTRACTAbstractPrevious theoretical work on range expansions over heterogeneous environments showed that there is a critical environmental gradient where range expansion stops. For populations with freely recombining loci underlying the trait under selection (hereafter, "adaptive loci"), the critical gradient in one-dimensional habitats depends on the fitness cost of dispersal and the strength of selection relative to genetic drift. Here, we extend the previous work in two directions and ask, What is the role of the recombination rate between ...
Source: The American Naturalist - April 28, 2021 Category: Biology Authors: Martin Eriksson Marina Rafajlovi ć Source Type: research

Correction
Am Nat. 2021 May;197(5):624. doi: 10.1086/713711. Epub 2021 Mar 18.NO ABSTRACTPMID:33908833 | DOI:10.1086/713711 (Source: The American Naturalist)
Source: The American Naturalist - April 28, 2021 Category: Biology Authors: Benjamin G Freeman Micah N Scholer Mannfred M A Boehm Julian Heavyside Dolph Schluter Source Type: research

Unprecedented Biting Performance in Herbivorous Fish: How the Complex Biting System of Pomacentridae Circumvents Performance Trade-Offs
Am Nat. 2021 May;197(5):E156-E172. doi: 10.1086/713498. Epub 2021 Mar 19.ABSTRACTAbstractIt is well accepted that the complexity of functional systems may mitigate performance trade-offs. However, data supporting this theory are hard to find because they need to be based on a functional system with different complexity levels in closely related species. The Pomacentridae (damselfishes) provide an excellent opportunity to test this hypothesis because most of the species have two mouth-closing systems: the first using the adductor mandibulae, as in all teleost fishes, and the second relying on the ceratomandibular (cmd) liga...
Source: The American Naturalist - April 28, 2021 Category: Biology Authors: Damien Olivier Sam Van Wassenbergh Eric Parmentier Bruno Fr édérich Source Type: research

Accelerated Brain Shape Evolution Is Associated with Rapid Diversification in an Avian Radiation
Am Nat. 2021 May;197(5):576-591. doi: 10.1086/713664. Epub 2021 Mar 22.ABSTRACTAbstractNiche expansion is a critical step in the speciation process. Large brains linked to improved cognitive ability may enable species to expand their niches and forage in new ways, thereby promoting speciation. Despite considerable work on ecological divergence in brain size and its importance in speciation, relatively little is known about how brain shape relates to behavioral, ecological, and taxonomic diversity at macroevolutionary scales. This is due in part to inherent challenges with quantifying brain shape across many species. Here w...
Source: The American Naturalist - April 28, 2021 Category: Biology Authors: Chad M Eliason Jenna M McCullough Michael J Andersen Shannon J Hackett Source Type: research

On Deleterious Mutations in Perennials: Inbreeding Depression, Mutation Load, and Life-History Evolution
In this study, we investigate this hypothesis. We combine a physiological growth model and multilocus population genetics approaches to describe a full genotype-to-phenotype-to-fitness map. We study the behavior of mutations affecting growth or survival and explore their consequences in terms of inbreeding depression and mutation load. Although our results agree with empirical data only within a narrow range of conditions, we argue that they may point us toward the type of traits capable of generating high inbreeding depression in long-lived species-that is, traits under sufficiently strong selection, on which selection de...
Source: The American Naturalist - April 28, 2021 Category: Biology Authors: Thomas Lesaffre Sylvain Billiard Source Type: research

The Allometry of Sound Frequency Bandwidth in Songbirds
Am Nat. 2021 May;197(5):607-614. doi: 10.1086/713708. Epub 2021 Mar 11.ABSTRACTAbstractTheory predicts that allometric constraints on sound production should be stronger for the lower frequencies of vocalizations than for the higher frequencies, which could originate from an allometry for sound frequency bandwidth. Using song recordings of approximately 1,000 passerine species (from>75% passerine genera), we show a significantly steeper allometry for the lower song frequencies than for the higher song frequencies, resulting in a positive allometry of frequency bandwidth: larger species can use wider bandwidths than smal...
Source: The American Naturalist - April 28, 2021 Category: Biology Authors: Jakob Isager Friis Joana Sabino Pedro Santos Torben Dabelsteen Gon çalo C Cardoso Source Type: research

Rethinking Gloger's Rule: Climate, Light Environments, and Color in a Large Family of Tropical Birds (Furnariidae)
Am Nat. 2021 May;197(5):592-606. doi: 10.1086/713386. Epub 2021 Mar 23.ABSTRACTAbstractEcogeographic rules provide a framework within which to test evolutionary hypotheses of adaptation. Gloger's rule predicts that endothermic animals should have darker colors in warm/rainy climates. This rule also predicts that animals should be more rufous in warm/dry climates, the so-called complex Gloger's rule. Empirical studies frequently demonstrate that animals are darker in cool/wet climates rather than in warm/wet climates. Furthermore, sensory ecology predicts that, to enhance crypsis, animals should be darker in darker light en...
Source: The American Naturalist - April 28, 2021 Category: Biology Authors: Rafael S Marcondes Jonathan A Nations Glenn F Seeholzer Robb T Brumfield Source Type: research

The Evolution of Social Dominance through Reinforcement Learning
Am Nat. 2021 May;197(5):560-575. doi: 10.1086/713758. Epub 2021 Mar 30.ABSTRACTAbstractGroups of social animals are often organized into dominance hierarchies that are formed through pairwise interactions. There is much experimental data on hierarchies, examining such things as winner, loser, and bystander effects, as well as the linearity and replicability of hierarchies, but there is a lack evolutionary analyses of these basic observations. Here I present a game theory model of hierarchy formation in which individuals adjust their aggressive behavior toward other group members through reinforcement learning. Individual t...
Source: The American Naturalist - April 28, 2021 Category: Biology Authors: Olof Leimar Source Type: research

Dispersal Alters the Nature and Scope of Sexually Antagonistic Variation
Am Nat. 2021 May;197(5):543-559. doi: 10.1086/713739. Epub 2021 Apr 7.ABSTRACTAbstractIntralocus sexual conflict, or sexual antagonism, occurs when alleles have opposing fitness effects in the two sexes. Previous theory suggests that sexual antagonism is a driver of genetic variation by generating balancing selection. However, most of these studies assume that populations are well mixed, neglecting the effects of spatial subdivision. Here, we use mathematical modeling to show that limited dispersal changes evolution at sexually antagonistic autosomal and X-linked loci as a result of inbreeding and sex-specific kin competit...
Source: The American Naturalist - April 28, 2021 Category: Biology Authors: Ewan O Flintham Vincent Savolainen Charles Mullon Source Type: research

Density-Dependent and Species-Specific Effects on Self-Organization Modulate the Resistance of Mussel Bed Ecosystems to Hydrodynamic Stress
Am Nat. 2021 May;197(5):615-623. doi: 10.1086/713738. Epub 2021 Mar 24.ABSTRACTAbstractSelf-organized, regular spatial patterns emerging from local interactions among individuals enhance the ability of ecosystems to respond to environmental disturbances. Mussels self-organize to form large, regularly patterned biogenic structures that modify the biotic and abiotic environment and provide numerous ecosystem functions and services. We used two mussel species that form monospecific and mixed beds to investigate how species-specific behavior affects self-organization and resistance to wave stress. Perna perna has strong attach...
Source: The American Naturalist - April 28, 2021 Category: Biology Authors: Gerardo I Zardi Katy R Nicastro Christopher D McQuaid Monique de Jager Johan van de Koppel Laurent Seuront Source Type: research

The Genetic Architecture of Fitness Drives Population Viability during Rapid Environmental Change
Am Nat. 2021 May;197(5):511-525. doi: 10.1086/713469. Epub 2021 Mar 22.ABSTRACTAbstractThe rapid global loss of biodiversity calls for improved predictions of how populations will evolve and respond demographically to ongoing environmental change. The heritability (h2) of selected traits has long been known to affect evolutionary and demographic responses to environmental change. However, effects of the genetic architecture underlying the h2 of a selected trait on population responses to selection are less well understood. We use deterministic models and stochastic simulations to show that the genetic architecture underlyi...
Source: The American Naturalist - April 28, 2021 Category: Biology Authors: Marty Kardos Gordon Luikart Source Type: research

The Effect of the Recombination Rate between Adaptive Loci on the Capacity of a Population to Expand Its Range
Am Nat. 2021 May;197(5):526-542. doi: 10.1086/713669. Epub 2021 Apr 8.ABSTRACTAbstractPrevious theoretical work on range expansions over heterogeneous environments showed that there is a critical environmental gradient where range expansion stops. For populations with freely recombining loci underlying the trait under selection (hereafter, "adaptive loci"), the critical gradient in one-dimensional habitats depends on the fitness cost of dispersal and the strength of selection relative to genetic drift. Here, we extend the previous work in two directions and ask, What is the role of the recombination rate between ...
Source: The American Naturalist - April 28, 2021 Category: Biology Authors: Martin Eriksson Marina Rafajlovi ć Source Type: research

Correction
Am Nat. 2021 May;197(5):624. doi: 10.1086/713711. Epub 2021 Mar 18.NO ABSTRACTPMID:33908833 | DOI:10.1086/713711 (Source: The American Naturalist)
Source: The American Naturalist - April 28, 2021 Category: Biology Authors: Benjamin G Freeman Micah N Scholer Mannfred M A Boehm Julian Heavyside Dolph Schluter Source Type: research

Unprecedented Biting Performance in Herbivorous Fish: How the Complex Biting System of Pomacentridae Circumvents Performance Trade-Offs
Am Nat. 2021 May;197(5):E156-E172. doi: 10.1086/713498. Epub 2021 Mar 19.ABSTRACTAbstractIt is well accepted that the complexity of functional systems may mitigate performance trade-offs. However, data supporting this theory are hard to find because they need to be based on a functional system with different complexity levels in closely related species. The Pomacentridae (damselfishes) provide an excellent opportunity to test this hypothesis because most of the species have two mouth-closing systems: the first using the adductor mandibulae, as in all teleost fishes, and the second relying on the ceratomandibular (cmd) liga...
Source: The American Naturalist - April 28, 2021 Category: Biology Authors: Damien Olivier Sam Van Wassenbergh Eric Parmentier Bruno Fr édérich Source Type: research

Accelerated Brain Shape Evolution Is Associated with Rapid Diversification in an Avian Radiation
Am Nat. 2021 May;197(5):576-591. doi: 10.1086/713664. Epub 2021 Mar 22.ABSTRACTAbstractNiche expansion is a critical step in the speciation process. Large brains linked to improved cognitive ability may enable species to expand their niches and forage in new ways, thereby promoting speciation. Despite considerable work on ecological divergence in brain size and its importance in speciation, relatively little is known about how brain shape relates to behavioral, ecological, and taxonomic diversity at macroevolutionary scales. This is due in part to inherent challenges with quantifying brain shape across many species. Here w...
Source: The American Naturalist - April 28, 2021 Category: Biology Authors: Chad M Eliason Jenna M McCullough Michael J Andersen Shannon J Hackett Source Type: research

On Deleterious Mutations in Perennials: Inbreeding Depression, Mutation Load, and Life-History Evolution
In this study, we investigate this hypothesis. We combine a physiological growth model and multilocus population genetics approaches to describe a full genotype-to-phenotype-to-fitness map. We study the behavior of mutations affecting growth or survival and explore their consequences in terms of inbreeding depression and mutation load. Although our results agree with empirical data only within a narrow range of conditions, we argue that they may point us toward the type of traits capable of generating high inbreeding depression in long-lived species-that is, traits under sufficiently strong selection, on which selection de...
Source: The American Naturalist - April 28, 2021 Category: Biology Authors: Thomas Lesaffre Sylvain Billiard Source Type: research

The Allometry of Sound Frequency Bandwidth in Songbirds
Am Nat. 2021 May;197(5):607-614. doi: 10.1086/713708. Epub 2021 Mar 11.ABSTRACTAbstractTheory predicts that allometric constraints on sound production should be stronger for the lower frequencies of vocalizations than for the higher frequencies, which could originate from an allometry for sound frequency bandwidth. Using song recordings of approximately 1,000 passerine species (from>75% passerine genera), we show a significantly steeper allometry for the lower song frequencies than for the higher song frequencies, resulting in a positive allometry of frequency bandwidth: larger species can use wider bandwidths than smal...
Source: The American Naturalist - April 28, 2021 Category: Biology Authors: Jakob Isager Friis Joana Sabino Pedro Santos Torben Dabelsteen Gon çalo C Cardoso Source Type: research

Rethinking Gloger's Rule: Climate, Light Environments, and Color in a Large Family of Tropical Birds (Furnariidae)
Am Nat. 2021 May;197(5):592-606. doi: 10.1086/713386. Epub 2021 Mar 23.ABSTRACTAbstractEcogeographic rules provide a framework within which to test evolutionary hypotheses of adaptation. Gloger's rule predicts that endothermic animals should have darker colors in warm/rainy climates. This rule also predicts that animals should be more rufous in warm/dry climates, the so-called complex Gloger's rule. Empirical studies frequently demonstrate that animals are darker in cool/wet climates rather than in warm/wet climates. Furthermore, sensory ecology predicts that, to enhance crypsis, animals should be darker in darker light en...
Source: The American Naturalist - April 28, 2021 Category: Biology Authors: Rafael S Marcondes Jonathan A Nations Glenn F Seeholzer Robb T Brumfield Source Type: research

The Evolution of Social Dominance through Reinforcement Learning
Am Nat. 2021 May;197(5):560-575. doi: 10.1086/713758. Epub 2021 Mar 30.ABSTRACTAbstractGroups of social animals are often organized into dominance hierarchies that are formed through pairwise interactions. There is much experimental data on hierarchies, examining such things as winner, loser, and bystander effects, as well as the linearity and replicability of hierarchies, but there is a lack evolutionary analyses of these basic observations. Here I present a game theory model of hierarchy formation in which individuals adjust their aggressive behavior toward other group members through reinforcement learning. Individual t...
Source: The American Naturalist - April 28, 2021 Category: Biology Authors: Olof Leimar Source Type: research