A comparative study of modern proteins identifies 40 fragments that may represent the observable remnants of a primordial RNA-peptide world.

Minimal changes allow an ancestral, unfolded peptide to adopt a known fold by repetition, illuminating a possible path for the emergence of folded proteins at the origin of life.

Ostrich eggshell from the Liushu Formation in northwestern China push ancient protein preservation into the Miocene.

Starfish feed by everting their stomach out of their mouth over prey and, interestingly, this unusual feeding mechanism is inhibited by substances similar to hormones that regulate feeding in humans.

Evolutionary reconstruction of the ecdysis pathway shows that its major elements are present in the majority of metazoans, providing evidence that they originated much earlier than currently assumed.

Analysis of the endogenous function of deeply conserved neuropeptides in sea anemones sheds light on a primitive role of nervous systems in modulating developmental timing.

Sloth1 and Sloth2 are two mitochondrial peptides that are translated from one transcript and are important for neuronal function in Drosophila.

A chemically unstable ostrich eggshell peptide survives for at least 3.8 million years at the equator, stabilized by strong mineral interactions.

A remarkable case of the common evolutionary origin of a prominent spider venom component.

Subterranean fossil bone hosts a living microbiome different from the surrounding sediment without evidence of original protein preservation.