Ancient duplication events and a high rate of retention of extant pairs of duplicate genes
have contributed to an abundance of duplicate genes in plant genomes. These duplicates …

The emergence of animals from their unicellular ancestors is a major evolutionary event.
Thanks to the study of diverse close unicellular relatives of animals, we now have a better …

The central insight of Darwin's Origin of Species is that evolution is an ecological
phenomenon, arising from the activities of organisms in the'struggle for life'. By contrast, the …

Evolutionary novelties have been important in the history of life, but their origins are usually
difficult to examine in detail. We previously described the evolution of a novel trait, aerobic …

The cytokine transforming growth factor–β (TGF-β) converts naïve T cells into regulatory T
(Treg) cells that prevent autoimmunity. However, in the presence of interleukin-6 (IL-6), TGF …

One of the most prominent features of the human brain is the fabulous size of the cerebral
cortex and its intricate folding. Cortical folding takes place during embryonic development …

Itch is one of the most primal sensations, being both ubiquitous and important for the well-
being of animals. For more than a century, a desire to understand how itch is encoded by the …

Cerebral cortex size differs dramatically between reptiles, birds, and mammals, owing to
developmental differences in neuron production. In mammals, signaling pathways …

Life on earth is characterized by three striking phenomena that demand explanation:
adaptation—the marvelous fit between organism and environment; diversity—the great …

Evolution of the mammalian brain encompassed a remarkable increase in size of the
cerebral cortex, which includes tangential and radial expansion. However, the mechanisms …