BIO 4113 Lecture Notes - Lecture 5: Dorsal Nerve Cord, Carl Linnaeus, Hominidae
Document Summary
Aristotle - scala natura - animals with blood and without. People were looking for any filing system to keep track of animals. Groupings of 3 or 5 based on mystical ideas concerning nature. None were practical, used folk or local naming - not latin. Hierarchical grouping of species based on shared key characters. Darwin claims the fact that it works shows shared ancestry. Character - any trait used in taxonomy (morphological, behavioral, and molecular) Continuous - length of tibia, height, iq - can be put into decimal. Meristic - number of teeth or scales. Four incisors and two pectoral nipples - primata. Bipedal, intelligence and tool use - homosapien. Chemoheterotrophs - have to eat to get energy. Systematics - common ancestry, the only known source of propinquity. Taxis = order, nomos = law or scheme. Approach to systematics - assumes shared characteristics and reflects homology. Clades include species with an exclusive common ancestor. Clade is tetrapods (group of related species)
