The insect odorant receptor gene family evolved at the base of the class Insecta before the evolution of flight and perhaps as an adaptation to terrestriality, and was therefore an important evolutionary novelty for insects.

Apicomplexan-like parasites originated several times independently and many of them contain cryptic plastid organelles, which demonstrate that the parasites evolved from photosynthetic algae.

X-ray imaging reveals well-preserved internal characters in mineralized arthropods from the Paleogene, urging the reexamination of previously neglected fossil collections.

Parasitic lineages of Rozellomycota are shaped by repeated and independent gene losses.

The discovery of the earliest direct evidence of brood care in insects demonstrates a remarkably conserved egg-brooding reproductive strategy within scale insects in stasis for nearly 100 million years.

A phylogeny of all major groups of flatworms based on hundreds of genes sheds new light the early evolution of this important metazoan phylum, with particular significance for the original of vertebrate parasitism.

Teeth are maintained in two amphibian groups (caecilians and salamanders) but were lost in frogs over 20 times independently, a higher incidence of edentulism than any other major vertebrate group.

The morphology of the inner ear distinguishes major anthropoid clades and enables the proposal of various shared-derived features for apes as a whole, lesser apes, and great apes and humans.

A new taxon from the Late Jurassic of southern Germany represents the second volant bird known from that time period and documents the improvement of flapping flight in bird evolution.

Flying squirrels may have originated earlier than previously thought and remained unchanged for almost 12 million years.