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18: Birds & Mammals

  • Page ID
    218628
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    • 18.1: Bird Structure and Diversity
      The most obvious characteristic that sets birds apart from other modern vertebrates is the presence of feathers, which are modified scales. While vertebrates like bats fly without feathers, birds rely on feathers and wings, along with other modifications of body structure and physiology, for flight.
    • 18.2: Mammal Structure and Diversity
      Mammals are vertebrates that possess hair and mammary glands. Several other characteristics are distinctive to mammals, including certain features of the jaw, skeleton, integument, and internal anatomy. Modern mammals belong to three clades: monotremes, marsupials, and eutherians (or placental mammals).
    • 18.3: The Evolution of Primates
      Order Primates of class Mammalia includes lemurs, tarsiers, monkeys, apes, and humans. Non-human primates live primarily in the tropical or subtropical regions of South America, Africa, and Asia. They range in size from the mouse lemur at 30 grams (1 ounce) to the mountain gorilla at 200 kilograms (441 pounds). The characteristics and evolution of primates is of particular interest to us as it allows us to understand the evolution of our own species.


    This page titled 18: Birds & Mammals was last modified on Fri, 28 Aug 2026 23:54:45 GMT and is shared under a not declared license and was authored, remixed, and/or curated by OpenStax.

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