co32 - CHAPTER 32 HUMAN EVOLUTION Chapter Outline 32.1...

Info icon This preview shows pages 1–2. Sign up to view the full content.

View Full Document Right Arrow Icon
C HAPTER 32 H UMAN E VOLUTION Chapter Outline 32.1 Evolution of Primates A. Primate Characteristics 1. Primates differ from other mammals by being adapted for arboreal life (life in trees). 2. Mobile Forelimbs and Hindlimbs a. In primates, the limbs are mobile and the hands and feet have five digits each. b. In most primates, flat nails replace claws and sensitive pads develop on the underside of fingers and toes. c. Many primate hands have to some extent an opposable thumb; some also have an opposable big toe. d. These features allow the free grasping of tree limbs and easy harvesting of fruit. 3. Binocular Vision a. Primates have a reduced snout and the face is relatively flat. b. The sense of smell is generally reduced. c. The eyes are moved to the front of the face for overlapping views that provide stereoscopic vision. d. Cone cells provide greater visual acuity and color vision but require bright light. 4. Large Complex Brain a. Better senses requires both sense organs and a more complex brain to process the input. b. More of the brain becomes devoted to processing information received from the hands and thumb, less to smell. 5. Reduced Reproductive Rate a. Primates have more single births, which reduces the need for care for several offspring. b. The period of parental care is extended with an emphasis on learned behavior and complex social interactions. B. Phylogenetic Tree 1. All primates at one time shared one common ancestor; prosimians were an early group to diverge and African apes were the last group to diverge from our lineage. 2. Prosimians diverged first and are most closely related to the original primate. 3. Anthropoids a. Surviving anthropoids are classified into three superfamilies: New World monkeys, Old World monkeys and hominoids. b. New World monkeys reside in South America and Old World monkeys evolved in Africa. c. New World monkeys (e.g., spider monkey and capuchin) have long prehensile tails and flat noses. d. Old World Monkeys (e.g., baboon and rhesus monkey) lack prehensile tails and have protruding noses. e. It is hypothesized that a common ancestor must have arisen earlier than the Oligocene when a narrower Atlantic would have made dispersal possible. 4. Ape Evolution a. During the Miocene epoch, dozens of hominoid species arose. b. Proconsul was one of several ape species prevalent in Africa during the Miocene and is believed ancestral to apes and humans.
Image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Image of page 2
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

What students are saying

  • Left Quote Icon

    As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

    Student Picture

    Kiran Temple University Fox School of Business ‘17, Course Hero Intern

  • Left Quote Icon

    I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

    Student Picture

    Dana University of Pennsylvania ‘17, Course Hero Intern

  • Left Quote Icon

    The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

    Student Picture

    Jill Tulane University ‘16, Course Hero Intern