Prosimians progressed or advanced to become Anthropoids
Evolved before Anthropoids.
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.
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.
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
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 suite of characteristics shared by primates has been explained as the result of adaptation to arboreal living.”
“Primates found their adaptive niche in the trees”
Also see Pg 117 for visual predation hypothesis.
New World: southern Mexico, Central America, and parts of South America.
Old World: Africa, India, Southeast Asia and Japan.
Old World monkeys (some) have adapted to life on the ground in places where trees are sparsely distributed.
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
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
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.
Species that brachiate tend to have arms that are longer than legs, a short, stable lower back’ long curved fingers and reduced thumbs.
prehensile tails are restricted to new world monkeys and aren’t seen in any old world primate species.
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.
-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
-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.
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
Example: Humans are slightly sexually dimorphic for body size, with males being taller, on average, than females of the same population.
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)
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