BIOA01H3 Lecture 4: Lec04_A01_Evidence2_Sept9_2014_partA.pdf

• School: UTSC
• Department: Biological Sciences
• Course: BIOA01H3
• Professor: Maydianne Andrade

Document Summary

2. 2 lineages should change over time and sometimes diverge (speciate) 2. 3 natural selection occurs & leads to adaptation. If life on earth evolved from a single ancestor we should see: some traits held in common by all life, evidence of changes in the organisms present on earth over time, transitional forms, vestigial characters. Fossils or organisms that show intermediate states between an ancestral form and that of its descendants: expected to be modified versions of ancestral forms, are not necessarily part of the direct line of descent. See an overview of numerous transitional forms at: https://www. youtube. com/watch?v=kftbrhg8kgq. Life evolved from a common ancestor fish amphibia amniotes. 2. 1 c. transitional forms: whale evolution, terrestrial to aquatic, position of nostrils, loss of hindlimbs. 2. 1 c. transitional forms: whale evolution www. evolution. berkeley. edu. 2. 1 c. transitional forms: horse evolution e. g. , miohippus and parhippus are transitional forms between. Hyracotherium & equus, showing progressive loss of digits www. evolution. berkeley. edu. ~ 5 million years older than earliest birds http://www. bbc. co. uk/nature/life/sinornithosaurus.