BIO152H5 Lecture Notes - Lecture 9: Radiometric Dating, Biogeography
Document Summary
Lecture 9 evolution: central unifying concept in biology. Pattern of evolution: darwin described evolution as descent with modification: change over time produced modern species from ancestral species, the theory of evolution by natural selection makes two claims about the nature of species: Fossils: traces of organisms that lived in the past, evidence of change through time. Descent with modification: darwin interpreted fossils as evidence that extinct forms and living forms are related, that they represent ancestors and descendants. Transitional forms: traits that are intermediate between older and younger species. Evidence for human evolution: earl(cid:455) fossils su(cid:272)h as (cid:862)lu(cid:272)(cid:455)(cid:863) provide evide(cid:374)(cid:272)e that the earliest hu(cid:373)a(cid:374) a(cid:374)(cid:272)estors arose in africa, using radiometric dating, scientists have estimate the age of fossil human ancestors. Hierarchical: large groups share general characteristics, and small groups share many specific characteristics. Classification of humans: humans are classified with apes because they share many biological characteristics.
