The Primates

Baby chimp

The Primates

Linnaean Taxonomy The idea that species shared similarities so

struck Swedish botanist Carolus Linnaeus that he devised a taxonomic system to name and thus categorize all living creatures.

Cladistics A Linnaean taxonomy can be translated

into an evolutionary tree. Cladistics works the opposite way by

starting with the evolutionary tree and placing organisms in taxonomic categories based on their order of branching regardless of how their present-day

appearances and adaptations might assort them into groups.

The Primates

A survey of the Living Primates Prosimians

The “pre-apes” represent the most primitive primates, that is, those that most closely resemble the earliest primates. There are 40 or so living species of prosimians.

Lemurs, Loris, Tarsiers

The Primates

Anthropoids The anthropoid (“humanlike”) primates include monkeys, apes, and humans.

All the New World platyrrhine primates are monkeys.

The Old World catarrhine primates comprise monkeys, apes, and humans.

Ringtailed lemur

Red fronted lemur

Black lemur

orangatan

capuchin

Uakari monkey

gorillas

The Primates

What is a Primate? Primates range from the very small,

such as the mouse lemur of Madagascar, which weighs less than 3 ounces, to

the gigantic- Gigantopithecus, an extinct ape from China, Vietnam, and India that may have stood 12 feet tall and weighed over half a ton.

The Primates:Characteristics The Senses

Vision is the primates’ predominant sense. Most primates see in color, and all primates see in three dimensions.

Movement Unlike most mammals, primates

have extremely flexible limbs, and their hands have the ability to grasp objects.

Reproduction Mostly because of their large, complex

brains and because of the importance of learning, young primates are dependent on adults and take a long time to mature.

Intelligence Of all land mammals, the primates

have the largest relative brain sizes. Omnivores Dirual Most of the primates live during the

day

Stereoscopic Vision Three-dimensional vision: depth perception.

Prehensile Having the ability to grasp.

Brachiation Locomotion by swinging arm-over-arm.

Opposability The ability to touch the thumb to the tips of

the other fingers on the same hand.

Postnatal Dependency The period after birth during which offspring require

the care of adults to survive.

Intelligence The relative ability of the brain to acquire, store,

retrieve, and process information.

Grooming Here, cleaning the fur of another animal, which

promotes social cohesion.

Dominance Hierarchy Individual differences among group members in

terms of power, influence, and access to resources and mating.

The Primates

The Senses Our senses are essentially the same as

those of the anthropoid monkeys and the apes.

Movement Bipedalism is the characteristic that in

broad evolutionary perspective defines the hominids.

We are the only primate that is habitually bipedal, and we have been for over 4 million years.

The Primates

Summary Taxonomy provides us with a way of

naming and categorizing species so as to indicate their biological relationships.

The primates are one of nineteen order of mammals.

They may be characterized as being adapted to arboreal environments through manual dexterity, visual acuity, and intelligence.

Tool making.

definitions

Inclusive Fitness The idea that fitness is measured by the success of

one’s genes, whether possessed by the individual or by that individual’s relatives.

Altruistic Benefiting others without regard for one’s own needs

or safety.

Reproductive Strategies Behaviors that evolve to maximize an individual’s

reproductive success.

Ethology The study of the natural behavior of animals under

natural conditions.

Primate behavior and Human Evolution

Baboons There are five distinguishable types of

baboon that live in the African woodland, desert, and savanna, all grouped within genus Papio.

Baboon groups range in size from 20 to 200 individuals. One of the most striking aspects of baboon behavior is the aggressive competition for dominance among males.

Primate Behavior and Human Evolution Chimpanzees

The bond between mother and infant is strong in chimps, as it is in most mammals. These apes, though, have large, complex brains, and infants have a lot to learn about their world before they can become functioning adults. Thus, the mother-infant bond is particularly long-lived and important.

Primate Behavior and Human Evolution Bonobos

Bonobos are more peaceful and gregarious than chimps. There is a dominance hierarchy among males, but unlike the case with chimpanzees, the hierarchy is easily established with brief aggressive chases. Female hierarchies appear to be based on seniority.

Primate Behavior and Human Evolution Summary

The importance of a well-defined social organization is seen among one savanna primate, the baboon, and is a good hint that an analogous behavior was a key to the survival of early savanna hominins.

The basic pattern for the behavior of chimps, bonobos, and humans are homologous. They are the same because we inherited them from a common ancestor.