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24.3: Selection Pressures and Drivers

  • Page ID
    29616
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    1. Competition with gymnosperms. Gymnosperms were large, successful organisms adapted to a variety of severe conditions. To compete with this group, angiosperms would need to work smarter, not harder.
    2. Birds and mammals. The diversity of animals present on Earth when angiosperms evolved would have resulted in increased seed predation. Fruits allowed for the dual purpose of protecting seeds and co-opting animals as dispersal agents, whether by ingestion or attachment. Some fruits evolved production of sugary tissues and bright colors to attract animals, while others evolved hairs or spines to latch onto their bodies.

    Contributors and Attributions


    This page titled 24.3: Selection Pressures and Drivers is shared under a CC BY-NC license and was authored, remixed, and/or curated by Maria Morrow (ASCCC Open Educational Resources Initiative) .

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