BIOL 111 Lecture Notes - Lecture 17: Seed Dispersal, Flowering Plant, Adaptive Radiation

• School: McGill University
• Department: Biology
• Course: BIOL 111
• Professor: Andrew Hendry

Document Summary

Advantages of pollen and seeds: no longer required water to reproduce, more varied dispersal of male gametes (via pollen, better dispersal of sexual offspring. Angiosperm radiation ----angiosperms dominate in diversity: adaptive radiation: when one lineage produces an unusually high numbers of descendant species adapted to many habitats, angiosperms one of great adaptive radiations in the history of life. 11000 ferns (2nd most diverse group of land plants) Female: ovules develop in the ovary: male: pollen develop in the anther. Seed dispersal (most seed-dispersal structures develop from ovary wall or tissue) Just as pollination predated flowers, animal seed dispersal may have predated fruits. Involved changes in water conductance(xylem) but gymnosperms had xylem too. Involved flowers but gymnosperms had pollinators too: associated with seed dispersal but gymnosperms had animal seed dispersers too, angiosperms dominate in diversity but not large parts of terrestrial world (taiga)