Though seemingly bizarre, the dramatic post-embryonic transformation that occurs during metamorphosis is one of the most widespread and successful developmental strategies on the planet. The adaptive decoupling hypothesis (ADH) proposes that metamorphosis is an adaptation for optimizing expression of traits across life stages that experience opposing selection pressures. Similarly, sex-biased expression of traits is thought to evolve in response to sexually antagonistic selection. Both hypotheses...
Mon Aug 31, 2020 03:00
Spatial and temporal environmental variation can favor the evolution of adaptive phenotypic plasticity, such that genotypes alter their phenotypes in response to local conditions to maintain fitness across heterogeneous landscapes. When individuals show greater fitness in one habitat than another, asymmetric migration can restrict adaptive responses to selection in the lower quality environment. In these cases, selection is predicted to favor traits that enhance fitness in the higher-quality source...
Mon Aug 31, 2020 03:00
Nuclear and plastid (chloroplast) genomes experience different mutation rates, levels of selection, and transmission modes, yet key cellular functions depend on coordinated interactions between proteins encoded in both genomes. Functionally related proteins often show correlated changes in rates of sequence evolution across a phylogeny (evolutionary rate covariation or ERC), offering a means to detect previously unidentified suites of coevolving and cofunctional genes. We performed phylogenomic analyses...
Mon Aug 31, 2020 03:00
Despite its amazing biodiversity, the Eastern Mediterranean remains a highly understudied region especially when compared to the Western Mediterranean. Scarcity of such studies restrict our understanding of the processes shaping diversity across the entire Mediterranean. To this end we used a combination of molecular markers and presence/absence data from all species of the Eastern Mediterrranean genus Ricotia collected across its full geographic range to determine historical, ecological and evolutionary...
Mon Aug 31, 2020 03:00
Multiple infection (when a single cell can become super-infected with multiple copies of virus) can effect evolutionary processes in HIV infection, such as the generation and spread of different mutations. Synaptic transmission (where multiple copies of virus can be transferred during a single cell-to-cell interaction) leads to an increase in infection multiplicity. Here, we analyze the effect of multiple infection on the evolution of an HIV infection using a hybrid stochastic-deterministic algorithm....
Mon Aug 31, 2020 03:00
Gene paralogs are copies of a same gene that appear after gene or full genome duplication. Redundancy generated by gene duplication may release certain evolutionary pressures, allowing one of the copies to access novel gene functions. Here we focused on role of codon usage preferences (CUPrefs) during the evolution of the polypyrimidine tract binding protein PTBP splicing regulator paralogs. PTBP1-3 show high identity at the amino acid level (up to 80%), but display different nucleotide composition,...
Mon Aug 31, 2020 03:00
Although molecular data have proven indispensable in confidently resolving the phylogeny of many clades across the tree of life, these data may be inaccessible for certain taxa. The resolution of taxonomy in the ant subfamily Leptanillinae is made problematic by the absence of DNA sequence data for leptanilline taxa that are known only from male specimens, including the monotypic genus Phaulomyrma Wheeler & Wheeler. Focusing upon the considerable diversity of undescribed male leptanilline morphospecies,...
Mon Aug 31, 2020 03:00
Differentiated sex chromosomes are believed to be evolutionarily stable, and their emergence was suggested to lead to a remarkable increase in the diversification rate and in disparity in such groups as birds, mammals and snakes. On the other hand, poorly differentiated sex chromosomes are considered to be prone to turnovers. With around 1.700 currently known species forming c. 15% of reptile species diversity, skinks (family Scincidae) are a very diverse group of squamates known for their large...
Mon Aug 31, 2020 03:00
Gene mutations endowing herbicide resistance may have negative pleiotropic effects on plant fitness. Quantifying these effects is critical for predicting the evolution of herbicide resistance and developing management strategies for herbicide resistant weeds. This study reports the effects of the acetohydroxyacid synthase (AHAS) Trp574Leu mutation throughout the life cycle of the weed feral radish (Raphanus sativus L.). Resistant and susceptible biotypes responded differently to light and water treatments...
Mon Aug 31, 2020 03:00
Mutation is a biased stochastic process, with some types of mutations occurring more frequently than others. Previous work has used synthetic genotype-phenotype landscapes to study how such mutation bias affects adaptive evolution. Here, we consider 746 empirical genotype-phenotype landscapes, each of which describes the binding affinity of target DNA sequences to a transcription factor, to study the influence of mutation bias on adaptive evolution of increased binding affinity. By using empirical...
Mon Aug 31, 2020 03:00
Public goods games (PGGs) describe situations in which individuals contribute to a good at a private cost, but others can free-ride by receiving their share of the public benefit at no cost. PGGs can be nonlinear, as often observed in nature, whereby either benefit, cost, or both are nonlinear functions of the available public good (PG): at low levels of PG there can be synergy whereas at high levels, the added benefit of additional PG diminishes. PGGs can be local such that the benefits and costs...
Mon Aug 31, 2020 03:00
Climate change affects organisms worldwide with profound ecological and evolutionary consequences, often increasing population extinction risk. Climatic factors can increase the strength, variability or direction of natural selection on phenotypic traits, potentially driving adaptive evolution. Phenotypic plasticity in relation to temperature can allow organisms to maintain fitness in response to increasing temperatures, thereby buying time for subsequent genetic adaptation and promoting evolutionary...
Mon Aug 31, 2020 03:00
AO_SCPLOWBSTRACTC_SCPLOWO_ST_ABSPremiseC_ST_ABSUnderstanding the relationship between genetic structure and geography provides information about a species evolutionary history and can be useful to breeders interested in de novo domestication. The North American prairie is especially interesting because of its relatively recent origin and subsequent dramatic fragmentation and degradation. Silphium integrifolium is an iconic perennial American prairie wildflower targeted for domestication as an oilseed...
Mon Aug 31, 2020 03:00
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