ANT203H5 Lecture Notes - Lecture 4: Toe, Prognathism, Stereopsis
Document Summary
Scientists use systematics to create phylogenies use a set of rules to understand how organisms evolve and are related. Phylogenetics: taxonomy + evolutionary relationships: linnaean system of taxonomy. Homoplasy: no shared ancestry: due to convergent evolution (same traits because adapted to similar environments: phylogenetic tree groupings. Polyphyletic: shared traits (homoplasies: characters of an organism. Shared derived synapomorphic most useful for grouping organisms into clades; identified using an outgroup. Unique derived autapomorphic: different approaches to classification. Phonetics overall similarity, equally weighing all traits. Cladistics (best approach) based solely on synapomorphies. E. g. what traits are shared derived, ancestral, unique. Primates are extremely diverse in biology and behaviour. Mostly confined to the tropical latitudes forested habitats. Vertebral column; bilateral symmetry; presence of a cranium. Homeothermy; hair or fur; inner ear ossicles (bones); females have mammary glands; heterodontic (different types of teeth); four-chambered heart; relatively large forebrain and cerebrum; increased parental care.
