BIOL 102 Lecture 7: bio 102 7
Document Summary
Convergent evolution: organisms are not closely related evil similar adaptations, analogous structures: structures have very different genetic origins, however share similar functions, ex. sharks and dolphins have ns, ex. 2 birds, bats, and some insects have wings: parallel evolution: in parallel evolution related species are physically separated but still evolve similar features in their different locations. Origin of earth: 4. 5 billion years ago. Advent of photosynthesis: 2. 5 billion years ago. Origins of life: essential elements: to compose organic molecules, continual source of energy: continual source of light (the sun, temperature range permitting liquid water. Explaining early earth is like trying to explain whether a chicken came before an egg or vice versa. Geological evidence for early life: stromatolites - - microfossil signatures that are created by the successive fossilization of different microbes. Tuesday, february 14, 2017: microfossils, biosignatures - - chemical indicators of life, isotope relations, cyanobacterial hopanoids, miss.
