The longer duration of seasonal influenza virus infection in young children may provide opportunities for within-host evolution as a result of maintenance of genetic diversity through mutation-selection balance.

A model of pathogen co-evolving with host population continuously acquiring immunity is used to identify evolutionary parameters allowing pathogen population to persist without going extinct or splitting into independent lineages.

A series of selective events, each improving fitness relative to an immediate predecessor, can result in organisms that are less fit compared to a distant ancestor.

Influenza evolution within infected hosts recapitulates many evolutionary dynamics observed at the global scale.

Mutations in the TRIM5α retrovirus-binding interface frequently improve but rarely disrupt retroviral restriction.

An in silico reconstruction of a chloroplast that existed hundreds of millions of years ago casts new insights in the evolutionary processes, endosymbioses and chimerism events that shape the origin of plastids.

The most recent common ancestor of humans, chimpanzees, and bonobos possessed a foot adapted to terrestrial quadrupedalism and climbing.

The synthesis capability of some amino acids is lost during the insect evolution, and hymenopteran parasitoids can make up for these deficiencies by altering free amino acid concentrations in host.

A population of pathogenic bacteria is found to respond to the loss of cooperation by privatising an essential function.

Mathematical modelling suggests that the evolution of communication between bacterial viruses requires repeated outbreak events, and the model then predicts typical communication strategies.