Chapter 3 The Living Primates

Chapter Preview What Is the Place of Humanity among the Other Animals? What Are the Characteristics of the Primates Inhabiting the World Today? Why Is Primate Conservation of Vital Importance to Anthropologists Today?

Primatology Biologists classify humans as belonging to the primate order, a mammalian group that also includes lemurs, lorises, tarsiers, monkeys, and apes. Primatology is the study of the biology, behavior, and evolutionary history of our closest living relatives, the non-human primates.

The Methods and Ethics of Primatology Primatologists study the biology and behavior of living non-human primates both in their natural habitats and in captivity at zoos, primate research colonies, or learning laboratories.

The Methods and Ethics of Primatology: For Class Discussion What are the advantages and disadvantages to studying primates in their natural habitats? What are the advantages and disadvantages to studying primates in captivity?

The Methods and Ethics of Primatology To cope with the problems of studying primates in the wild, primatologists have developed many noninvasive methods For example, they gather hair, feces, or other body secretions left by the primates in the environment for later analysis in the laboratory

The Methods and Ethics of Primatology Work with captive animals provides more than knowledge about the basic biology of primates. It has also allowed primatologists to document the “humanity” of our closest living relatives in terms of understanding their skill with language.

Our Place in Nature This is the full name of our species!!! Domain: Eukaryota Kingdom: Animalia Phylum: Chordata Subphylum: Vertebrata Class: Mammalia Order: Primates Superfamily: Hominoidea Family: Hominidae Subfamily: Homininae Genus: Homo Species: sapiens Subspecies: sapiens This is the full name of our species!!!

Our Place in Nature: Primates as Mammals Like reptiles and birds, mammals have lungs. Mammals are warm-blooded like the birds (and maybe the dinosaurs). Mammals have fur or hair. Female mammals produce milk. Mammals have large brain sizes compared to their bodies. There are only about 5,000 species of mammals, compared to 22,000 species of fish, but they live everywhere.

Visual Counterpoint: Class Discussion When there is competition from the anthropoid primates, Prosimian species such as this slender loris (right) retain the arboreal nocturnal patters of the earliest fossil primates. While ring-tailed lemurs (left) have remained diurnal.

Visual Counterpoint: Class Discussion What physical traits do lemurs and lorises share because of their shared ancestry (either as prosimians or as strepsirhini)? What physical traits appear to be related to their contrasting diurnal and nocturnal adaptations?

Primate Taxonomy: 2 Schemes Based on genetic relationships, primates are divided into: Strepsirhini (from the Greek for “turned nose”) – lemurs and lorises; and Haplorhini (Greek for “simple nose”) -- tarsiers, monkeys, apes, and humans. In the older taxonomic scheme,, primates are divided into prosimians (lemurs, lorises, and tarsiers), anthropoids (monkeys, apes, and humans) The anthropoid suborder is further divided into the Platyrrhini, or New World monkeys; and the Catarrhini, consisting of Old World monkeys, apes, and humans.

Primate Taxonomy The two taxonomies compared.

Primate Characteristics Generalized set of teeth (heterodonty), suited to insect eating but also fruits and leaves (omnivory). Depth perception Binocular stereoscopic vision with three-dimensional vision Intensified sense of touch (due to tactile pads on the digits) Opposable thumbs

Primate Characteristics Brain is large and heavy in proportion to body weight, and very complex. Skeleton has adaptations for upright posture and flexibility of limb movement. Few offspring born to each female and a longer period of infant dependency. Most primates are diurnal although some prosimians may retain the original nocturnal adaptation of early primates.

Primate Characteristics Compared to some animals with identical teeth; primates are heterdonts – they have different teeth with specific dental formulae (arrangement of different kinds of teeth).

Primate Characteristics Prosimians and Platyrrhines have a 2-1-3-3 dental formula. Catarrhines (including humans) have a 2-1-2-3 dental formula.

Primate Characteristics Anthropoid primates possess binocular stereoscopic vision. Binocular vision refers to overlapping visual fields associated with forward facing eyes. This leads to three-dimensional vision.

Primate Characteristics The primate braincase, or cranium, tends to be high and vaulted In humans, the vertebral column joins the skull toward the center of its base, less so for other primates. In anthropoid primates, the snout or muzzle portion of the skull is reduced In each primate arm or leg, the upper portion of the limb has a single long bone, the lower portion two long bones, and then hands or feet have five radiating digits (pentadactyly).

Distribution of Living and Fossil Primates

The Living Primates lemurs and lorises tarsiers New World monkeys Old World monkeys apes

Lemurs and Lorises Highly developed sense of smell for a primate (have a rhinarium) Claw-like fingernails Tend to be quadrupedal and arboreal Have tails

Tarsiers Smallest of the primates Claw-like fingernails Tend to be arboreal Have tails

The Monkeys Other than humans, the most widespread type of primate Larger than prosimians; they also have a tail Quadrupedal and can be either arboreal or terrestrial Two varieties – New World monkeys and Old World monkeys (along with apes and humans)

New World Monkeys Found only in tropical rainforests but have adapted to all levels of the canopy Tend to form large multi-family social groups Platyrrhines Some have prehensile tails

Old World Monkeys Found in a variety of environments – savanna, forest, snowy mountains Tend to form large multi-family social groups Catarrhines (like apes and humans)

The Living Primates Some Old World monkey species, like the proboscis monkey have specialized adaptations.

The Hominoids: Apes Largest of the primates in overall body size and brain size No visible tail Quadrupedal, Knuckle-walking, and Brachiation Have the most restricted habitats – tropical Central Africa and Southeast Asia Two varieties – Great Apes and Lesser Apes

The Great Apes Largest of the apes Tend to form large and complex groups Includes Chimpanzees, Bonobos, Gorillas, and Orangutans Primarily terrestrial but some are arboreal

The Lesser Apes Smallest of the apes Tend to form large and complex groups Includes Gibbons and Siamangs Primarily arboreal Restricted to Southeast Asia

Humans as Primates Opposable thumbs and prehensile hands SIMILARITIES Opposable thumbs and prehensile hands Diurnal (active during the day) Stereoscopic and Color Vision Like Old World monkeys and other Hominoids, we are catarrhines Like apes, we lack visible tails and have large bodies/brains DIFFERENCES Fully terrestrial (only arboreal for certain activities) Bipedal Unlimited range

Threats to Primate Survival All great apes are listed as endangered species Economic development (farming, lumbering, cattle ranching, rubber tapping), as well as by hunters and trappers who pursue them for food, trophies, research, or as exotic pets. Another threat to great apes comes from disease. There are over nineteen viruses and eighteen parasites that are known to infect both great apes and humans.

Primate Conservation Wars, logging, and mining in gorilla habitats not only destroy their forests, but roads make it easier for poachers to access the gorillas.

Primate Conservation Traditional conservation efforts emphasized habitat preservation above all else. Primatologists have been calling for new efforts that educate local communities, to curtail hunting primates for food and medicine to complement existing habitat preservation efforts.

Primate Conservation In direct conservation efforts, primatologists work to maintain some populations in the wild, either by establishing preserves where animals are already living or by moving populations to places where suitable habitat exists.