Scaffolding we built on:
- Life as a problem solved through evolution
- Dependence of organisms on ecology
- Multiple modes of evolution
- Natural selection
- Neutral drift
- Gene exchange
- Environmental/ecological roles in evolution
- Evolutionary innovation
- Symbiotic processes – mitochondria and chloroplasts
- Ecological systems
- Eating each other – cell lysing as in game last week
Feedbacks – a different way to think about interactions
- Evaluation of competition vs cooperation depends on “motivation”
- Do black and white daisies act cooperatively or competitively to stabilize temperatures in Daisyworld?
- Feedbacks produce ecological succession: example of fire ecology on wikipedia
- When positive feedbacks lead to too low a population, extinction occurs.
- Negative feedback lead to stability
Summary of Main Points:
- Ecological-environmental interactions shape natural selection
- Perspective of the scientist affects models for why something happened
- What actually happened is independent of scientists’ models, e.g. what we think doesn’t change what happened
- Getting all the same suit – parts of enzymes working better together
- Example: the Complex III protein and how it fits with the Cytochrome C molecule
- Lateral gene transfer:
- Transformation involves uptake of short fragments of naked DNA in the environment.
- Transduction involves transfer of DNA from one bacterium into another via (viruses).
- Conjugation involves transfer of DNA via sexual pilus and requires cell –to-cell contact.