BIO120H1 Lecture Notes - Lecture 16: Habitat, Histology, Stoma
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BIO120H1 Full Course Notes
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Lecture 16: tradeoffs and compromises: conclude and summarize physiological ecology of. Two reasons why natural selection produces deeply imperfect organisms. Tradeoffs: being good at x may necessarily imply being bad at y, constraints, selection builds on what is already there, especially existing on developmental programs. Tinkering, yes; fundamentally fresh design, no: weasels are long and skinny, not ideal for conserving heat in a cold environment, but prey lives underground in burrows. Dealing with extreme water stress: kangaroo rat (dipodomys), sonoran desert. In many situations, water balance is critical: don"t need water if they have an adequate diet of seeds, water comes from seed diet. Instead of four legs and stomach near ground, only two legs. Less conductive heat: efficient kidneys, extremely concentrated urine, nine times more concentrated don"t lose as much water, metabolic work requires a lot of energy. If they have built up their own fat, they can metabolize it.
