Diversity
- Created by: Louis James
- Created on: 02-01-13 19:12
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Biological Diversity - Lecture 1
- our perception = anthropocentric
- microorganisms = key - life
- earth formed (+ rest of solar system) - 4.5 billion years ago = 4.5×10(9)
- age earth - uranium-lead dating
- most common fossils - replacement, organic material after burial - minerals dissolved - water - ground + recrystallisation
- burial - tar = fantastic detail
- amber (fossilised tree resin) - soft tissues preserved
- fossil record - increasing complexity
- key moments - evolution:
- origin of life
- oxygenation atmosphere
- origin - eukaryotic cells
- origin - multicellular organisms
- Cambrian explosion
- colonisation - land, complex organisms
- Stanley Miller's experiment = electricity - provide energy - mixture gases, closed system - amino acids formed
- problem = atmosphere - different - gases used
- simple organic compounds - amino acids+nucleotides - throughout solar systems - comets+meteorites
- long popular theory - primordial soup, sea collected - amino acids+nucleotides, joined - macromolecules (protein+DNA). problem = not concentrated enough
- hypothesis now widely accepted = hydrothermal vents = more concentrated solution - organic molecules. energy - heat. Black smokers - ecosystems independent - sun
- earliest cells - bags, enabled higher concentrations nutrients build up
- first…
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