BIO120H1 Lecture Notes - Lecture 16: Histology, Habitat, Heart Rate
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BIO120H1 Full Course Notes
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Biology lecture 16: physiological ecology of animals, synthesis: tradeoffs and compromises. Two reasons why natural selection produces deeply imperfect organisms: tradeoffs (in terms of strategies used to deal with the stress of the environment) Being good at x may necessarily imply being bad at y. A physiology that bene ts solving one problem make it dif cult to solve another issue. Tness, it spreads: adjusting rather than going back to the drawing board. Selection builds on what is already there, especially existing developmental programs. Dealing with extreme water stress: kangaroo rat (dipodomys), sonoran desert. In the desert; the main areas of stress stem from heat and lack of water (temperature and access to water) K-rat tactics for conserving water in hot, dry environments. Erect posture (stands up rather than crawling around and having body and belly in contact with the ground) , bipedal; less heat gain from ground.
