AN101 Ch6

members of a suborder of primates, the Prosimii (pronounced “pro-sim-ee-eye”) Traditionally, the suborder includes lemurs, lorises and tarsiers.
Prosimians progressed or advanced to become Anthropoids
Evolved before Anthropoids.
Members of a suborder of Primates, the Anthropoidea (pronounced “ann-throw-poid-ee-uh”) Traditionally the suborder includes monkeys, apes and humans.
Share numerous characteristics with other placental mammals.
Body Hair
Relatively long gestational period followed by live birth
mammary glands (hence the term mammal)
different types of teeth
Endothermy- the ability to maintain a constant internal body temperature through physiological means.
increased brain size
considerable capacity for learning and behavioral flexibility.
Evolved for a particular function; usually refers to a specific trait (e.g. incisor teeth) but may also refer to an organisms entire way of life.
Example: horses and cattle have undergone a reduction in the number of digits from the ancestral pattern of five to one and two respectively. In addition, they have developed hard, protective coverings over their feet in the form of hooves.
scientists who study the evolution, anatomy, and behavior of nonhuman primates. Those who study behavior in free-ranging animals are usually trained as physical anthropologists.
Primate Characteristics
Page 115
This is a set of general tendencies that aren’t equally expressing in all primates but are meant to give an overall structural and behavioral picture of the animals we call Primates
A. Limbs and Locomotion
1. A tendency toward erect posture (especially the upper body).
2. A flexible, generalized limb structure allows most primates to practice a number of locomotor activities.
3. Hands and feet with a high degree of prehensility (grasping ability)
a.Retention of five digits on hands and feet
b.An opposable thumb and, in most species, a divergent and partially opposable big toe.
c. Nails instead of claws
d.Tactile pads enriched with sensory nerve fibers at the ends of digits.

B. Diet and teeth
1.Lack of dietary specialization.
2. A generalized dentition.

C.The senses and the brain
1.Color vision.
2. Depth perception. Stereoscopic vision or, the ability to perceive objects in three dimensions
a. Eyes positioned toward the front of the face, not the sides.
b.Visual information from each eye transmitted to visual centers in both hemispheres of the brain.
c. Visual information organized into three-dimensional images by specialized structures in the brain itself.
3. decreased reliance on the sense of smell. (olfaction)
4. Expansion and increased complexity of the brain.

D. Maturation, learning and behavior.
1. A more efficient means of fetal nourishment, longer periods of gestation, reduced numbers of offspring (with single births the norm), delayed maturation, and extension of the entire lifespan.
2. A greater dependence on flexible, learned behavior.
3.The tendency to live in social groups and the permanent association of adult males with the group.
4. The tendency to dinural activity patterns.

The form (shape, size) of anatomical structures; can also refer to the entire organism.
Grasping, as by the hands and feet of primates
Having a diet consiting of many kinds of foods, such as plant materials (seeds, fruit, leaves), meat and insects.
Active during the day.
Active during the night.
Stereoscopic Vision
The condition whereby visual images are, to varying degrees, superimposed on one another. This trait provides for depth perception, or the perception of the external environment in three dimensions.Stereoscopic vision is partly a function of structures in the brain.
Binocular Vision
Vision characterized by overlapping visual fields, provides for by forward facing eyes. Binocular vision is essential to depth perception.
environmental circumstances
climate, diet, habitat (woodland, grassland, forest, etc) and predation
Tree-living; adapted to live in trees.
“The suite of characteristics shared by primates has been explained as the result of adaptation to arboreal living.”
Adaptive niche
The entire way of life of an oganism: where it lives, what it eats, how it gets food, how it avoids predators, and so on.
“Primates found their adaptive niche in the trees”
Arboreal Hypothesis
the traditional view that primate characteristics can be explained as a consequence of primate diversification into arboreal habitats.

Also see Pg 117 for visual predation hypothesis.

sensory modalities
Different forms of sensation (e.g. touch, pain, pressure, heat, cold, vision, taste, hearing and smell).
The two halves of the cerebrum that are connected by a sense mass of fibers. (the cerebrum is the large, rounded, outer portion of the brain.)
Primates are found where?
With a couple exceptions, primates are found in tropical or semi-tropical areas of the New and Old Worlds.
New World: southern Mexico, Central America, and parts of South America.
Old World: Africa, India, Southeast Asia and Japan.
Primate habitats
Primarily arboreal – forest and woodland habitats
Old World monkeys (some) have adapted to life on the ground in places where trees are sparsely distributed.
dental formula
used by biologists to describe the number of each type fo tooth that typifies a species.
an anatomical term referring to a hypothetical line that divides the body into right and left halves.
the elevated portions (bumps) on the chewing surfaces of premolar and molar teeth.
carnivores typically have high pointed cusps adapted for eating meat.
herbivores typically have broad, flat surfaces suited to chewing tough grasses and other plant material
Using all four limbs to support the body during locomotion’ the basic mammalian (and primate) form of locomotion.
Most primates use more than one form of locomotion and are able to do this because of their generalized anatomy.
In arboreal quadrupeds, the forelimbs are somewhat shorter
Arm swinging. Another type of primate locomotion where the body is alternatively supported under wither forelimb.
A form of locomotion in which the body is suspended beneath the hands and support is alternated from one forelimb to the other; arm swinging.
Ex: Gibbons
Species that brachiate tend to have arms that are longer than legs, a short, stable lower back’ long curved fingers and reduced thumbs.
Some new world monkeys practice a combination of leaping with some arm swinging.
Prehensile tail
enhances arm swinging and suspensory behavior by acting as a grasping fifth “hand”
prehensile tails are restricted to new world monkeys and aren’t seen in any old world primate species.
primates – Class/Group/Subgroups
Mammalia/Primates/Prosimii & Anthropoidea
Comparative Genomics
Techniques of DNA sequencing used in the Human Genome Project make it possible to make direct between-species comparisons of DNA sequences.
The moist, hairless pad at the end of the nose, seen in most mammals. the rhinarium enhances an animals ability to smell.
Prosimians exhibit certain more ancestral characteristics, such as a more pronounced reliance on olfaction. Their greater olfactory capabilities (compared to other primates) are reflected in the presence of a rhinarium at the end of the nose and in a relatively long snout.
New World Monkeys
-Exhibit a wide range of size, diet and ecological adaptation.
-Are almost exclusively arboreal, and some never come to the ground.
-All except for one species (the owl monkey) are dinural
-Divided into two families: Callitichidae (marmosets and tamarins) and Cebidae (all others).
-roughly 70 species
Old World Monkeys
-Except for humans, they are the most widely distributed of all living primates
-Most are quadrupedal and primarily arboreal, but some (baboons) are also adapted to life on the ground.
-They spend a good deal of time sleeping, feeding and grooming.
-Have areas of hardened skin on the buttocks (ischial callosities) that serve as sitting pads.
-placed into one taxonimic family: Cercopithecidae which is divided into two subfamilies: cercopithecines and colobines.
Ischial Callosities
Patches of tough, hard skin on the buttocks of Old World Monkeys and chimpanzees
The family designation for all the Old Wold monkeys
The subfamily of Old World monkeys that includes babboons, macaques and guenons.
More generalized of the two groups
more omnivorous dietary adaptation
cheek pouches for storing food
eat almost anything – fruit, seeds, leaves, grasses, tubers, roots, nuts, insects, birds eggs, amphibians, small reptiles, and small mammals.
majority of the species are found in Africa.
The subfamily of Old World monkeys that includes the African colobus monkeys and Asian langurs.
narrower range of food preferences, mainly eating mature leaves, which is why they’re also called leaf-eating monkeys.
Found mainly in Asia
Tend to live in small groups with one or two adult males
Monogamous pairing isn’t common in Old World monkeys
Sexual Dimorphism
Differences in physical characteristics between males and females of the same species.
Example: Humans are slightly sexually dimorphic for body size, with males being taller, on average, than females of the same population.
(ess-truss) Period of sexual receptivity in female mammals (except humans), correlated with ovulation. When used as an adjective, the work is spelled estrous.
The formal designation for the superfamily of anthropoids that includes apes and humans.
The family designation of the gibbons and siamangs that live in parts of southeast Asia.
The traditional family designation of the great apes (orangutans, chimpanzees, bonobos, and gorillas)
Apes and Humans differ from Monkeys in 7 ways.
1. Generally larger body size, except for gibbons and siamangs
2. Absence of a tail.
3. Shortened trunk (lumbar area shorter and more stable)
4. Differences in position and musculature of the shoulder joint (adapted for suspensory locomotion)
5. More complex behavior
6. More complex brain and enhances cognitive abilities.
7. Increased period of infant development and dependency.
Having a diet composed of primarily fruit
Knuckle Walking
A form of locomotion used by chimpanzees, bonobos, and gorillas wherein, the weight of the upper body is supported on the knuckles rather than on the palms of the hands.
Natal Group
The group in which animals are born and raised.