Sexual antagonism, mating systems, and recombination suppression on sex chromosomes

Using population-genetic models, this study demonstrates that even weak sexual antagonism dramatically accelerates the evolution of recombination suppression on sex chromosomes compared to neutrality, with mating systems and the genomic origin of suppressors (heterogametic vs. homogametic) critically shaping the rate and direction of this evolutionary process in both XY and ZW systems.

Flintham, E., Mullon, C.2026-02-19📄 evolutionary biology

Direct and indirect benefits of cooperation in collective defense against predation

This study demonstrates that in the social pine sawfly *Neodiprion sertifer*, collective defense against predation provides both direct and indirect (kin-selected) survival benefits, with individuals strategically modulating their contributions based on group size, sex ratio, and kinship to balance cooperation against the risk of exploitation.

Ritter, R., Helanterä, H., Tynkkynen, R. + 2 more2026-02-19📄 evolutionary biology

Transcriptional Activation of Estrogen Receptor-alpha and Estrogen Receptor-beta from Elephant Shark (Callorhynchus milii)

This study reveals that the elephant shark (*Callorhynchus milii*) possesses three novel estrogen-responsive ER genes alongside an ER{beta} ortholog, demonstrating that despite the discovery of additional ER variants, the transcriptional activation of these receptors by estrogens remains substantially conserved with humans over 425 million years of evolution.

Ao, Y., Narita, H., Takagi, W. + 3 more2026-02-19📄 evolutionary biology

Multiple ecological and evolutionary mechanisms drive treatment-induced antibiotic resistance

By analyzing nearly 25,000 *Pseudomonas aeruginosa* isolates from bronchiectasis patients, this study reveals that treatment-induced antibiotic resistance arises through diverse ecological and evolutionary mechanisms, including the predominance of pre-existing resistance, selective sweeps of costly mutations, and oscillating dynamics driven by trade-offs between subpopulations.

Shepherd, M. J., Harrington, N. E., Kottara, A. + 8 more2026-02-19📄 evolutionary biology

A classification of structured coalescent processes with migration, conditional on the population pedigree

This paper extends coalescent theory to account for population subdivision and migration by conditioning on specific population pedigrees, revealing that traditional models fail to capture significant pedigree effects in most scenarios except for the well-known structured-coalescent model, with a notable exception involving intermittent gene flow.

Lessard, S., Easlick, T., Wakeley, J.2026-02-19📄 evolutionary biology

In silico identification and deorphanisation of an allatostatin C GPCR system in the cephalopod Octopus vulgaris reveals two receptors with distinct potency

This study identifies and characterizes a conserved allatostatin C neuropeptide system in the octopus *Octopus vulgaris*, revealing a single peptide that differentially activates two distinct receptors with broad tissue distribution, suggesting a critical role in sensory processing and nociception with significant implications for cephalopod welfare.

Pieroni, E. M., Dillon, J., O'Connor, V. + 4 more2026-02-19📄 evolutionary biology

Environmental perturbation increases gene expression variability and unmasks genetic regulation for transcriptional robustness

This study demonstrates that environmental stress, specifically a high-sugar diet, increases gene expression variability across the transcriptome while simultaneously revealing a distinct, evolutionarily constrained genetic architecture (veQTL) that regulates this variability, particularly in key developmental pathways.

Phipps-Tan, J., Alishayeva, S., Xu, H. + 2 more2026-02-19📄 evolutionary biology

Population specific bottlenecks inflated differentiation measures of Louisiana black bear and negate subspecific status

This study concludes that the Louisiana black bear's previously recognized subspecific status is unsupported because its high genetic differentiation stems primarily from historical population bottlenecks and drift rather than distinct adaptive evolution, suggesting conservation efforts should prioritize maintaining genetic diversity over subspecies recognition.

Puckett, E. E., Clendenin, H. R.2026-02-19📄 evolutionary biology

Constrained evolution of a core winter proteome across independently cold-adapted PACMAD grasses

This study demonstrates that independently cold-adapted PACMAD grasses exhibit a constrained, conserved protein-level response to freezing, particularly through the retention and structural optimization of LEA3 proteins, suggesting that functional freezing tolerance relies on ancestral protective mechanisms rather than lineage-specific innovations.

Oren, E., Zhai, J., Rooney, T. E. + 11 more2026-02-18📄 evolutionary biology

Dental calculus as a record of Pleistocene reindeer oral, digestive and dietary flora

This study utilizes ancient metagenomic analysis of dental calculus from Pleistocene and modern reindeer to reconstruct their oral and digestive microbiomes and diets, revealing both long-term continuity in rumen adaptations and spatio-temporal shifts in microbial and dietary profiles driven by ecological differences between ancient France and contemporary Scandinavia.

Kellner, F. L., Brealey, J. C., Vogel, N. + 8 more2026-02-18📄 evolutionary biology

Stable but turbulent: the two faces of the germline-restricted chromosome of passerine birds

This study presents high-quality assemblies of germline-restricted chromosomes (GRCs) in four passerine birds, revealing that while these essential chromosomes retain a few ancestral genes, they undergo rapid, species-specific expansion of repetitive sequences and extensive rearrangements driven by programmed DNA elimination, creating a paradox of stable function amidst extraordinary structural dynamism.

Schlebusch, S. A., Halenkova, Z., Moreno, H. + 8 more2026-02-18📄 evolutionary biology