These animals were living in an environment with a warm climate that results in changing sea levels. These conditions create a lot of shallow inland seas allowing these animals to thrive. The Cretaceous period is the last period of the Mesozoic area where new groups of mammals, birds, and flowering plants appeared on Earth.
The genes involved in pattern formation and organization of body parts are called homeobox genes, which are a large family of similar genes.
The h<span>omeobox genes direct the formation of many body structures during early development of the embryo. </span>
Photothenysis disorder plants leafs dying
