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Variability in Fecundity–Body Size Relationships for Atlantic Salmon Associated With Body Condition and Life HistoryNARA Subscribed
While body size is the primary driver of fecundity, other factors may contribute to variation in these relationships. Anadromous populations of Atlantic salmon ( Salmo salar ) have diverse life histories, and fisheries management relies on accurate fecundity estimates. We used Bayesian hierarchical models to determine the relationship between fecundity and fork length, and other life‐history characteristics, for 25 spawning po...
Pleistocene glaciations have shaped much of the population divergence events in the coniferous forests of North America. However, unlike in western North America, the evidence for forest fragmentation and population divergence associated with glacial cycles is less clear in the boreal forests of eastern North America. Here, we present the first genomic analysis of an avian hybrid zone in the eastern North American boreal fores...
Several legal acts mandate that management agencies regularly assess biological populations. For species with distinct markings, these assessments can be conducted noninvasively via capture‐recapture and photographic identification (photo‐ID), which involves processing considerable quantities of photographic data. To ease this burden, agencies increasingly rely on automated identification (ID) algorithms. Identification algori...
Genomic Analysis Suggests That Mitonuclear Coevolution Proceeds Over Rapid Timescales in the Amazonian Pipra Manakin ComplexNARA Subscribed
Mitonuclear coevolution is defined as reciprocal selection between the nuclear and mitochondrial genomes and is necessary to maintain compatibility between nuclear‐ and mitochondrially‐encoded products that interact during mitochondrial processes including mitochondrial genome replication, transcription and translation and oxidative phosphorylation. Theory predicts that mitonuclear coevolution may play a crucial role in the ea...
Aim The Amazon rainforest is one of the most biodiverse regions on earth, but our understanding of the processes that have shaped its patterns of diversity remains incomplete. One hypothesis for Amazonian speciation is the river‐refuge hypothesis, which suggests that retraction of forests away from the periphery of Amazonia, where rivers are narrow, facilitated divergence of populations separated by wide rivers. Later re‐expan...
Knowledge of genetic diversity and structure is essential for developing conservation strategies for endangered species. Blue whales were hunted to near extinction in the mid-twentieth century. Not-withstanding almost 380,000 animals killed globally, much remains unknown about their population structure and migration patterns. Herein, we use whole genome sequencing to elucidate the poorly understood population genetics of Nort...
Gene flow, genomic homogenization and the timeline to speciation in Amazonian manakinsNARA Subscribed
Phylogeographical studies of the most species‐rich region of the planet—the Amazon basin—have repeatedly uncovered genetically distinctive, allopatric lineages within currently named species, but understanding whether such lineages are reproductively isolated species is challenging. Here we harness the power of genome‐wide data sets together with detailed phylogeographical sampling to both characterize the number of unique lin...
Distinguishing genomic homogenization from parapatric speciation in an elevationally replacing pair of Ramphocelus tanagersNARA Subscribed
Geographically connected species pairs with weakly differentiated genomes could either represent cases of genomic homogenization in progress or of incipient parapatric speciation. Discriminating between these processes is difficult because intermediate stages of either may produce weakly differentiated genomes that diverge at few locations. We used coalescent modelling applied to a genome‐wide sample of SNPs to discriminate be...
Geographic contact drives increased reproductive isolation in two cryptic Empidonax flycatchersNARA Subscribed
Geographic contact between sister lineages often occurs near the final stages of speciation, but its role in speciation's completion remains debated. Reproductive isolation may be essentially complete prior to secondary contact. Alternatively, costly interactions between partially reproductively isolated species – such as maladaptive hybridization or competition for resources – may select for divergence, increasing reproductiv...
The long and narrow path for novel cell‐based seafood to reduce fishing pressure for marine ecosystem recoveryNARA Subscribed
Cell‐based seafood is an emerging novel food, with many start‐up companies aspiring for ocean conservation benefits through expanded market share that displaces wild‐caught seafood. However, the ability for cell‐based seafood to achieve this conservation outcome is often oversimplified and will rely on an extensive, and we find somewhat tenuous, chain of events. Here, we outline the technological, behavioural, market and ecolo...
Collisions with buildings cause up to 1 billion bird fatalities annually in the United States and Canada. However, efforts to reduce collisions would benefit from studies conducted at large spatial scales across multiple study sites with standardized methods and consideration of species‐ and life‐history‐related variation and correlates of collisions. We addressed these research needs through coordinated collection of data on...
Is Niagara Falls a barrier to gene flow in riverine fishes? A test using genome‐wide SNP data from seven native speciesNARA Subscribed
Since the early Holocene, fish population genetics in the Laurentian Great Lakes have been shaped by the dual influences of habitat structure and post‐glacial dispersal. Riverscape genetics theory predicts that longitudinal habitat corridors and unidirectional downstream water‐flow drive the downstream accumulation of genetic diversity, whereas post‐glacial dispersal theory predicts that fish genetic diversity should decrease...
Elevational differentiation accelerates trait evolution but not speciation rates in Amazonian birdsNARA Subscribed
The importance of ecologically mediated divergent selection in accelerating trait evolution has been poorly studied in the most species‐rich biome of the planet, the continental Neotropics. We performed macroevolutionary analyses of trait divergence and diversification rates across closely related pairs of Andean and Amazonian passerine birds, to assess whether the difference in elevational range separating species pairs – a p...
The role of sexual selection as a driver of speciation remains unresolved, not least because we lack a clear empirical understanding of its influence on different phases of the speciation process. Here, using data from 1306 recent avian speciation events, we show that plumage dichromatism (a proxy for sexual selection) does not predict diversification rates, but instead explains the rate at which young lineages achieve geograp...
Latitudinal gradients in climatic‐niche evolution accelerate trait evolution at high latitudesNARA Subscribed
Despite the importance of divergent selection to the speed of evolution, it remains poorly understood if divergent selection is more prevalent in the tropics (where species richness is highest), or at high latitudes (where paleoclimate change has been most intense). We tested whether the rate of climatic‐niche evolution – one proxy for divergent selection – varies with latitude for 111 pairs of bird species. Using Brownian mot...
Into and out of the tropics: the generation of the latitudinal gradient among New World passerine birdsNARA Subscribed
Aim One prominent explanation for the latitudinal gradient in biodiversity proposes that its prime cause is the greater age and/or higher origination rates of tropical clades, and the infrequent or delayed dispersal of their component species into temperate regions. An alternative is that species’ carrying capacities vary regionally, which influences rates of time‐averaged diversification via ecological opportunity. We contras...
Environmental harshness, latitude and incipient speciationNARA Subscribed
Are rates of evolution and speciation fastest where diversity is greatest – the tropics? A commonly accepted theory links the latitudinal diversity gradient to a speciation pump model whereby the tropics produce species at a faster rate than extra‐tropical regions. In this issue of Molecular Ecology, Botero et al . ( ) test the speciation pump model using subspecies richness patterns for more than 9000 species of birds and mam...
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