EARTH 7 Lecture Notes - Lecture 4: Species Complex, Most Shocking, Heritability
Document Summary
Darwin: species- group of viably interbreeding organisms, lineage- a species through time, divergence- when a lineage splits (aka speciation) Evolution: change of species overtime, not da(cid:396)(cid:449)i(cid:374)"s idea, la(cid:373)a(cid:396)ck"s ideas o(cid:374) e(cid:448)olutio(cid:374) (cid:449)e(cid:396)e al(cid:396)eady (cid:449)ell k(cid:374)o(cid:449)(cid:374) i(cid:374) da(cid:396)(cid:449)i(cid:374)"s ti(cid:373)e. E(cid:448)olutio(cid:374) does(cid:374)"t e(cid:395)ual natu(cid:396)al electio(cid:374): evolution is a process, natural selection, one mechanism explaining that process, not the mechanism, types of mechanisms: sexual selection, genetic drift, etc. Variation in a species: can be due to sexual reproduction/genetic variation, another source: change in sna (mutation, duplication, etc. ) Heritability of variation: variation genetically controlled, offspring resemble parents. Age of earth and life must be immense. Transitional forms: by late 1800s, fossils had already helped settle the debate about common descent with modification. New ideas to interpret new evidence: history of humans is not the same as the history of life, the great chain of being still incorrectly influences how we think. Nested hierarchy: animals led to vertebrat3es which led to mammals.
