BIO120H1 Lecture Notes - Lecture 3: Histology, Torpor, Habitat
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BIO120H1 Full Course Notes
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Lecture 3: physical challenges of environmental for animals, emphasis and trade-offs and. Fitness gains offset the costs of fitness costs. Phenotypes of all organisms are riddled with compromised dictated by tradeoffs. Natural selection- 2 reasons why deeply imperfect organisms are produced. Being good at x may necessarily imply being good at y. Constraints: selection builds on what is already there, tinkering only no completely fresh redesigns . Kangaroo rats deal with extreme water stresses, they have many tactics to combat and conserve water in these hot desert environments. Behaviour super-efficient kidneys metabolic water produced (where they break down fats to get h2o) nocturnal hides from the hot days and hunts during the cool nights cache seeds underground + recapture water vapor. Enter dormant stages (seeds, cysts, eggs, pupae, torpor) with minimal metabolism. Hibernate (get through a cold season) or estivate (describe animals to go through a hot season) as adult, store fat (drop metabolic rate to sleep through unfavourable seasons)
