BIO120H1 Lecture Notes - Lecture 14: Adaptive Radiation, Geochelone, Beagle Channel
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BIO120H1 Full Course Notes
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Lecture 14: what darwin saw a geographical perspective on biodiversity and adaptation. Charles darwin"s voyage on h. m. s beagle (1831-1836) Observations of fossils, geographical distribution of plant and animals, and flora and fauna of oceanic islands. Oak woodland in england characterized by low species diversity. Started off at british isle, first stop was brazil. Very high species diversity of plant and animal groups compared with temperate zone. Many more biotic interactions, especially coevolved mutualisms between plants and animals. Year-round warmth results in rapid growth of insect and microbial populations. Pest and disease pressures on plants are intense. Plants have evolved new strategies to deal with the pressure. Darwin observes high species diversity in trees (often up to 300 species), individuals of the same species are widely separated. Presented a conundrum of questions for darwin. Vastly different from temperate forests (which use wind as a method of dispersal for pollen)
