chordate animals
51circulation — circulable /serr kyeuh leuh beuhl/, adj. /serr kyeuh lay sheuhn/, n. 1. an act or instance of circulating, moving in a circle or circuit, or flowing. 2. the continuous movement of blood through the heart and blood vessels, which is maintained… …
52photoreception — photoreceptive, adj. /foh toh ri sep sheuhn/, n. the physiological perception of light. [1905 10; PHOTO + RECEPTION] * * * Biological responses to stimulation by light, most often referring to the mechanism of vision. In one celled organisms such …
53community ecology — Introduction study of the organization and functioning of communities (community), which are assemblages of interacting populations of the species living within a particular area or habitat. As populations of species interact with one …
54Evolution of mammals — Restoration of Thrinaxodon, a member of the cynodont group, which includes the ancestors of mammals Further information: Evolutionary history of life The evolution of mammals within the synapsid lineage (sometimes called mammal like reptiles )… …
55Brain — This article is about the brains of all types of animals, including humans. For information specific to the human brain, see Human brain. For other uses, see Brain (disambiguation). A chimpanzee brain The brain is …
56Maotianshan shales — In the Maotianshan shales is a lower Cambrian Konservat Lagerstätte named for Maotianshan Hill (zh stp|t=linktext|帽|天|山|s=linktext|帽|天|山|p=Màotiānshān) in Chengjiang County, Yunnan Province, China. More commonly, the extremely diverse assemblage… …
57Ascidiacea — Taxobox fossil range=fossil range|0|0|earliest=Silurian|text=Recent (but see text) name = Ascidiacea image width = 250px image caption = Halocynthia sp. regnum = Animalia phylum = Chordata subphylum = Urochordata classis = Ascidiacea classis… …
58Maotianshan Shales — Maotianshania cylindrica, a fossil nematomorph worm, Early Cambrian, Chengjiang Maotianshan Shales Part of a series on The Cambrian explosion …
59Invertebrate — The common fruit fly, Drosophila melanogaster, has been the subject of much research An invertebrate is an animal without a backbone. The group includes 97% of all animal species[1] – all animals except those in the …
60nature, philosophy of — Introduction the discipline that investigates substantive issues regarding the actual features of nature as a reality. The discussion here is divided into two parts: the philosophy of physics and the philosophy of biology. In this… …
