Competitive Displacement and Agonistic Character Displacement, or the Ghost of Interference Competition
Am Nat. 2024 Mar;203(3):335-346. doi: 10.1086/728671. Epub 2024 Jan 23.ABSTRACTAbstractInterference competition can drive species apart in habitat use through competitive displacement in ecological time and agonistic character displacement (ACD) over evolutionary time. As predicted by ACD theory, sympatric species of rubyspot damselflies (Hetaerina spp.) that respond more aggressively to each other in staged encounters differ more in microhabitat use. However, the same pattern could arise from competitive displacement if dominant species actively exclude subordinate species from preferred microhabitats. The degree to which...
Source: The American Naturalist - February 15, 2024 Category: Biology Authors: Shawn McEachin Jonathan P Drury Gregory F Grether Source Type: research

A Numerical Model Supports the Evolutionary Advantage of Recombination Plasticity in Shifting Environments
Am Nat. 2024 Mar;203(3):E78-E91. doi: 10.1086/728405. Epub 2024 Jan 18.ABSTRACTAbstractNumerous empirical studies have witnessed an increase in meiotic recombination rate in response to physiological stress imposed by unfavorable environmental conditions. Thus, inherited plasticity in recombination rate is hypothesized to be evolutionarily advantageous in changing environments. Previous theoretical models proceeded from the assumption that organisms increase their recombination rate when the environment becomes more stressful and demonstrated the evolutionary advantage of such a form of plasticity. Here, we numerically exp...
Source: The American Naturalist - February 15, 2024 Category: Biology Authors: Sviatoslav R Rybnikov Sariel H übner Abraham B Korol Source Type: research

Multigenerational Fitness Effects of Natural Immigration Indicate Strong Heterosis and Epistatic Breakdown in a Wild Bird Population
Am Nat. 2024 Mar;203(3):411-431. doi: 10.1086/728669. Epub 2024 Jan 24.ABSTRACTAbstractThe fitness of immigrants and their descendants produced within recipient populations fundamentally underpins the genetic and population dynamic consequences of immigration. Immigrants can in principle induce contrasting genetic effects on fitness across generations, reflecting multifaceted additive, dominance, and epistatic effects. Yet full multigenerational and sex-specific fitness effects of regular immigration have not been quantified within naturally structured systems, precluding inference on underlying genetic architectures and p...
Source: The American Naturalist - February 15, 2024 Category: Biology Authors: Lisa Dickel Peter Arcese Lukas F Keller Pirmin Nietlisbach Debora Goedert Henrik Jensen Jane M Reid Source Type: research

Variation in Avian Predation Pressure as a Driver for the Diversification of Periodical Cicada Broods
Am Nat. 2024 Mar;203(3):E92-E106. doi: 10.1086/728118. Epub 2024 Jan 17.ABSTRACTAbstractPeriodical cicadas live 13 or 17 years underground as nymphs, then emerge in synchrony as adults to reproduce. Developmentally synchronized populations called broods rarely coexist, with one dominant brood locally excluding those that emerge in off years. Twelve modern 17-year cicada broods are believed to have descended from only three ancestral broods following the last glaciation. The mechanisms by which these daughter broods overcame exclusion by the ancestral brood to synchronously emerge in a different year, however, are elusive. ...
Source: The American Naturalist - February 15, 2024 Category: Biology Authors: William L Huffmyer Fang Ji Julie C Blackwood Alan Hastings Walter D Koenig Andrew M Liebhold Jonathan Machta Karen C Abbott Source Type: research

Maintenance of Behavioral Variation under Predation Risk: Effects on Personality, Plasticity, and Predictability
Am Nat. 2024 Mar;203(3):347-361. doi: 10.1086/728421. Epub 2024 Jan 23.ABSTRACTAbstractClassic evolutionary theory predicts that predation will shift trait means and erode variance within prey species; however, several studies indicate higher behavioral trait variance and trait integration in high-predation populations. These results come predominately from field-sampled animals comparing low- and high-predation sites and thus cannot isolate the role of predation from other ecological factors, including density effects arising from higher predation. Here, we study the role of predation on behavioral trait (co)variation in ...
Source: The American Naturalist - February 15, 2024 Category: Biology Authors: David J Mitchell Christa Beckmann Peter A Biro Source Type: research

The Evolution of Local Co-occurrence in Birds in Relation to Latitude, Degree of Sympatry, and Range Symmetry
Am Nat. 2024 Mar;203(3):432-443. doi: 10.1086/728687. Epub 2024 Jan 19.ABSTRACTAbstractRecent speciation rates and the degree of range-wide sympatry are usually higher farther from the equator. Is there also a higher degree of secondary syntopy (coexistence in local assemblages in sympatry) at higher latitudes and, subsequently, an increase in local species richness? We studied the evolution of syntopy in passerine birds using worldwide species distribution data. We chose recently diverged species pairs from subclades not older than 5 or 7 million years, range-wide degree of sympatry not lower than 5% or 25%, and three def...
Source: The American Naturalist - February 15, 2024 Category: Biology Authors: Lenka Harm áčková Vladim ír Remeš Source Type: research

Density-Dependent Selection during Range Expansion Affects Expansion Load in Life History Traits
Am Nat. 2024 Mar;203(3):382-392. doi: 10.1086/728599. Epub 2024 Jan 18.ABSTRACTAbstractModels of range expansion have independently explored fitness consequences of life history trait evolution and increased rates of genetic drift-or "allele surfing"-during spatial spread, but no previous model has examined the interactions between these two processes. Here, using spatially explicit simulations, we explore an ecologically complex range expansion scenario that combines density-dependent selection with allele surfing to asses the genetic and fitness consequences of density-dependent selection on the evolution of life history...
Source: The American Naturalist - February 15, 2024 Category: Biology Authors: Mackenzie Urquhart-Cronish Amy L Angert Sarah P Otto Ailene MacPherson Source Type: research

Opening the Museum's Vault: Historical Field Records Preserve Reliable Ecological Data
Am Nat. 2024 Mar;203(3):305-322. doi: 10.1086/728422. Epub 2024 Jan 18.ABSTRACTAbstractMuseum specimens have long served as foundational data sources for ecological, evolutionary, and environmental research. Continued reimagining of museum collections is now also generating new types of data associated with but beyond physical specimens, a concept known as "extended specimens." Field notes penned by generations of naturalists contain firsthand ecological observations associated with museum collections and comprise a form of extended specimens with the potential to provide novel ecological data spanning broad geographic and...
Source: The American Naturalist - February 15, 2024 Category: Biology Authors: Viviana Astudillo-Clavijo Tobias Mankis Hern án López-Fernández Source Type: research

An Elevational Phylogeographic Diversity Gradient in Neotropical Birds Is Decoupled from Speciation Rates
Am Nat. 2024 Mar;203(3):362-381. doi: 10.1086/728598. Epub 2024 Jan 23.ABSTRACTAbstractA key question about macroevolutionary speciation rates is whether they are controlled by microevolutionary processes operating at the population level. For example, does spatial variation in population genetic differentiation underlie geographical gradients in speciation rates? Previous work suggests that speciation rates increase with elevation in Neotropical birds, but underlying population-level gradients remain unexplored. Here, we characterize elevational phylogeographic diversity between montane and lowland birds in the megadivers...
Source: The American Naturalist - February 15, 2024 Category: Biology Authors: Kristen S Wacker Benjamin M Winger Source Type: research

Inclusive Fitness May Explain Some but Not All Benefits Derived from Helping Behavior in a Cooperatively Breeding Bird
Am Nat. 2024 Mar;203(3):393-410. doi: 10.1086/728670. Epub 2024 Jan 24.ABSTRACTAbstractIn cooperative breeding systems, inclusive fitness theory predicts that nonbreeding helpers more closely related to the breeders should be more willing to provide costly alloparental care and thus have more impact on breeder fitness. In the red-cockaded woodpecker (Dryobates borealis), most helpers are the breeders' earlier offspring, but helpers do vary within groups in both relatedness to the breeders (some even being unrelated) and sex, and it can be difficult to parse their separate impacts on breeder fitness. Moreover, most support ...
Source: The American Naturalist - February 15, 2024 Category: Biology Authors: Natalie Z Kerr William F Morris Jeffrey R Walters Source Type: research

Competition Increases Risk of Species Extinction during Extreme Warming
Am Nat. 2024 Mar;203(3):323-334. doi: 10.1086/728672. Epub 2024 Jan 18.ABSTRACTAbstractTemperature and interspecific competition are fundamental drivers of community structure in natural systems and can interact to affect many measures of species performance. However, surprisingly little is known about the extent to which competition affects extinction temperatures during extreme warming. This information is important for evaluating future threats to species from extreme high-temperature events and heat waves, which are rising in frequency and severity around the world. Using experimental freshwater communities of rotifers...
Source: The American Naturalist - February 15, 2024 Category: Biology Authors: Paul Bendiks Walberg Source Type: research

Competitive Displacement and Agonistic Character Displacement, or the Ghost of Interference Competition
Am Nat. 2024 Mar;203(3):335-346. doi: 10.1086/728671. Epub 2024 Jan 23.ABSTRACTAbstractInterference competition can drive species apart in habitat use through competitive displacement in ecological time and agonistic character displacement (ACD) over evolutionary time. As predicted by ACD theory, sympatric species of rubyspot damselflies (Hetaerina spp.) that respond more aggressively to each other in staged encounters differ more in microhabitat use. However, the same pattern could arise from competitive displacement if dominant species actively exclude subordinate species from preferred microhabitats. The degree to which...
Source: The American Naturalist - February 15, 2024 Category: Biology Authors: Shawn McEachin Jonathan P Drury Gregory F Grether Source Type: research

A Numerical Model Supports the Evolutionary Advantage of Recombination Plasticity in Shifting Environments
Am Nat. 2024 Mar;203(3):E78-E91. doi: 10.1086/728405. Epub 2024 Jan 18.ABSTRACTAbstractNumerous empirical studies have witnessed an increase in meiotic recombination rate in response to physiological stress imposed by unfavorable environmental conditions. Thus, inherited plasticity in recombination rate is hypothesized to be evolutionarily advantageous in changing environments. Previous theoretical models proceeded from the assumption that organisms increase their recombination rate when the environment becomes more stressful and demonstrated the evolutionary advantage of such a form of plasticity. Here, we numerically exp...
Source: The American Naturalist - February 15, 2024 Category: Biology Authors: Sviatoslav R Rybnikov Sariel H übner Abraham B Korol Source Type: research

Multigenerational Fitness Effects of Natural Immigration Indicate Strong Heterosis and Epistatic Breakdown in a Wild Bird Population
Am Nat. 2024 Mar;203(3):411-431. doi: 10.1086/728669. Epub 2024 Jan 24.ABSTRACTAbstractThe fitness of immigrants and their descendants produced within recipient populations fundamentally underpins the genetic and population dynamic consequences of immigration. Immigrants can in principle induce contrasting genetic effects on fitness across generations, reflecting multifaceted additive, dominance, and epistatic effects. Yet full multigenerational and sex-specific fitness effects of regular immigration have not been quantified within naturally structured systems, precluding inference on underlying genetic architectures and p...
Source: The American Naturalist - February 15, 2024 Category: Biology Authors: Lisa Dickel Peter Arcese Lukas F Keller Pirmin Nietlisbach Debora Goedert Henrik Jensen Jane M Reid Source Type: research

Variation in Avian Predation Pressure as a Driver for the Diversification of Periodical Cicada Broods
Am Nat. 2024 Mar;203(3):E92-E106. doi: 10.1086/728118. Epub 2024 Jan 17.ABSTRACTAbstractPeriodical cicadas live 13 or 17 years underground as nymphs, then emerge in synchrony as adults to reproduce. Developmentally synchronized populations called broods rarely coexist, with one dominant brood locally excluding those that emerge in off years. Twelve modern 17-year cicada broods are believed to have descended from only three ancestral broods following the last glaciation. The mechanisms by which these daughter broods overcame exclusion by the ancestral brood to synchronously emerge in a different year, however, are elusive. ...
Source: The American Naturalist - February 15, 2024 Category: Biology Authors: William L Huffmyer Fang Ji Julie C Blackwood Alan Hastings Walter D Koenig Andrew M Liebhold Jonathan Machta Karen C Abbott Source Type: research