Evolutionary Biology

eLife assessment

This valuable study presents a novel and theoretically interesting model to account for viral diversity within hosts in evolutionary and genomic analyses of pathogens. The simulation results presented are solid, although there are some aspects of the methodology that require further investigation in order to establish their validity. The application to SARS-CoV-2 shows promise, but would benefit from further evaluation.

eLife assessment

This important study functionally characterizes hemoglobin from Steller's sea cow, a cold-water adapted sirenian that went extinct ~250 years ago. Using ancestral sequence reconstruction, site-directed mutagenesis and biochemical assays to compare Steller's hemoglobin to those from (sub)tropical extant sea cows (all of which are proficient divers despite lacking massive muscle oxygen storage), the authors build a solid case for the molecular basis of cold adaptation, centered around an increased solubility and higher oxygen carrying capacity. Remarkably, a single amino acid replacement would explain most of the distinctive functional features of this hemoglobin, which include a hitherto unknown resistance to DPG. Overall, this work will be of interest to evolutionary biologists, physiologists, and biochemists, as well as an enjoyable and informative read for the general public.

eLife assessment

This valuable paper sheds new light on the growth trajectory of bonobos (Pan paniscus), with explicit contributions to discussions of the exclusivity of certain aspects of growth in modern humans, most specifically with respect to components of the adolescent growth spurt, which may be less human-specific among primates than presumed to this point. The results are solid, based on the largest sample ever considered in the study of bonobo growth and include both morphometric and endocrinological data. This work will be of interest to human evolutionary biologists, primatologists, and researchers studying the ontogeny and evolution of growth and development in general.

eLife assessment

This study has important implications for the impact of sexual conflict on population viability under different temperatures. The authors propose that male harm to females in sexual conflict can be reduced as a function of temperature within the optimal reproductive range of a species. The evidence for this proposal is currently incomplete because there is methodological detail that needs to be further clarified. The results could have implications for the likelihood of the evolutionary rescue of species facing the climate crisis.

eLife assessment

This important study greatly expands our knowledge of the fossil record of Mermithid nematodes, modern members of which are ecologically important parasitoids of arthropods, annelids and mollusks today. The most important finding, convincingly presented, is that mermithids parasitized a number of insect clades in the Cretaceous that they are not known to infect today or in Cenozoic amber. The evidence for a shift in exploited hosts from heterometabolous insects in the Cretaceous to holometabolous ones in the Miocene is solid but could be made exceptional by adding a small quantitative analysis with confidence intervals and bar plots from the data already compiled in the supplementary material; potential collection bias should be addressed as well.

eLife assessment

This study presents convincing evidence that metabolite levels in Escherichia coli bacteria from a long-term evolution experiment have changed in consistent ways, which in turn can be explained by recurrent mutations in regulatory genes that affect enzyme expression levels. The use of high-resolution mass spectrometry measuring bulk metabolite levels, in combination with existing gene expression and DNA sequencing datasets provides valuable information linking changes in an organism's genome, transcriptome, and metabolome.

eLife Assessment:

This study is fundamental to understanding the intrinsic driving forces of gene losses during mammalian genome evolution, linking the propensity for gene losses to the local genomic features such as mutation rate and spatially restricted expression. In general, the study is methodologically convincing because independent gene losses in at least two mammalian lineages were identified as "elusive human genes". However, additional (comparative genomics and statistical) analyses would make the current study more rigorous. This manuscript will appeal to readers interested in the evolutionary fates of genes across the phylogenetic tree.

eLife assessment

This fundamental study by Rose and colleagues addresses key challenges in demographic inference in non-model systems with an innovative approach to model parameter calibration based on known historical events. Using this approach, they convincingly show that human specialization in Ae. aegypti mosquitoes likely evolved due to a past climate event around 5,000 years ago, and that recent rapid urbanization has continued to fuel its spread in West Africa in the past 20-40 years. This work will be of broad interest to population geneticists working on demographic inference, and to mosquito biologists working on the monitoring and control of this important vector species.

eLife assessment

This manuscript reports important findings regarding the evolution of snake venom proteins. The conclusions are convincing and are based on appropriate and validated methodology in line with the current state-of-the-art. The findings will be of interest to biologists and biochemists interested in the evolution of venoms as well as those generally interested in the evolution of molecular novelties.

eLife assessment

This study combines different approaches to unravel the genetic basis of a pigmentation polymorphism in natural populations of a fascinating study system with well-studied ecology. The paper has the potential to be of general interest to biologists curious about the genetic basis of adaptive variation, which is especially relevant to evolutionary biologists and ecologists. The study reports substantial data and makes a strong case for the contribution of a duplication-derived gene acquiring a morph-specific function. Further information is required to implicate valkea in pigmentation morph formation and for diagnosing the duplicated segment as a supergene (associated with low recombination).