Hox genes and their relatives are involved in several developmental processes in diverse animals, but when did they first arise? The genome sequence of the sponge Amphimedon queenslandica shows ...

Hox genes are clusters of regulatory genes that control development by turning other genes on and off. Biologists had attributed changes in the arthropod body plan to changes in Hox gene expression, ...

Later in an animal's development, epigenetic switches take over. These epigenetic mechanisms act to maintain the fate of cells by doing what the Hox genes and other transcription factors did ...

They targeted regions of the genome known to be involved in the development of an early embryo. This allowed them to control which genes were activated, and induce the creation of the main types ...