Textbook Notes (362,755)
Canada (158,052)
Anthropology (530)
ANTB14H3 (34)
Chapter 4

ANTB14 CH4.odt

8 Pages
Unlock Document

University of Toronto Scarborough
Michael Schillaci

CHAPTER 4: PRIMATES Why are ANTHROpologists interested in nonhuman primates? Primates are of interest to anthropologists because they can help us to study human evolution through the principal of homology. Because we share a common ancestor human and nonhuman primates are similar morphologically, physiologically, and even behaviorally. Primates is a diverse order. This diversity includes diet: some primates eat primarily leaves, while others rely on fruit, or insects, or even sap. Diversity in social organization: some primate taxa live in multimale groups, while others live in single male groups Diversity in activity patterns: some are active during the day (diurnal), others are active at nigh (nocturnal). General description of primates in terms of their form or structure, sensory and neural systems and life history of patterns -grasping hands & feet to hold on to trees -clavicle bone which allows for shoulder motion (imp for arboreal environments) -radius and ulna in forearm allows for movement of hand and arm -forward facing eyes and stereoscopic vision: they use both eyes to see, producing overlapping fields of vision >combines to form depth perception The opposable big toe or thumb, combined with flat nails rather than claws, allows primates to have a high level of precision grip. -they have enlarged visual and reduced olfactory centers in the brain Primates differ from other mammals in certain aspects of life history such as growth and development -long lifespan comprised of longer gestation, juvenile period and long period of infancy, childhood, and adulthood >traits assoc'd w learning necessary skills to forage for food, socialize, and reproduce w conspecifics Prosimians (or lesser primates) have wet noses (strepsirhine), an open orbit, and a higher level of olfaction. Anthropoids (higher primates), have dry noses (haplorhine), and closed orbits. Among lemurs, females are dominant. Many prosimians are nocturnal NEW WORLD MONKEYS Atelidae and Cebidae have prehensile tails, Callitrichids do not. Callitrichids are interesting because some species usually give birth to twins and live in polyandrous groups. The only nocturnal monkey is a NWM (Cebidae): Owl Monkey (Aotus trivirgatus). OLD WORLD MONKEYS AND APES Two subfamilies of cercopithecids: 1) colobinae, which are leaf eaters with specialized stomachs, and cercopithinae which have cheek pouches -dental tooth comb allows for grooming (consists mainly of incisors) -rhinarium nose assoc'd with enhanced sense of smell -they also have unfused symphases of the mandible (jawbone) and frontal bone of the skull -tapetum lucidum, biological system improving their ability to see in low intensity light -postorbital bar which is a ring around the eye socket -strepsirrhines have one infraorder (lemuriformes) and two superfamilies (lemuroidea and lorisoidea) >lemurs located in south east coast of Africa in Madagascar and Comoro Lemurs -Madagascar and Comoro Islands -arboreal quadrupeds (they use all for legs to move around) while some are terrestrial -vertical clinging and leaping: clinging to vertical or inclined substrate in upright position and then leaping toward and grasping another vertical or inclined substrate -diet consists of fruits, leaves, flowers & insects -small bodied lemurs are noctural and as a result have large eyeballs relative to body size -most larger lemurs are diurnal -female dominance in ecological and social settings Loris (superfamily term: Lorisoidea) -contains one primate family Lorisidae, known as lorises and galagos -range through forests of Sub-Saharan Africa and South East Asia -lorises resemble toy teddy bears -arboreal quadrupeds, using slow deliberate hand over hand movements in the trees -diet consists mainly of plant materials and insects -nocturnal, solitary foragers -most have evolved derived features: characteristics that differ from those of their ancestors which differentiate them from strepshirhines -all have dry nose and thus rely more on visual senses >therefore, they have retinal fovea, which reduces night vision but improves visual acuity -they have fused mandibular and frontal symphases, EXCEPT tarsiers which retain the PRIMITIVE trait seen in strepshirrhines -all haplorhines EXCEPT for tarsiers have nails, instead of claws >tarsiers retain grooming claws on two of their toes -three infraorders: 1) tarsiiformes including tarsiers -they are found in many parts of South East Asia -smallest bodied primates >its eyeball is larger than its brain -fused lower leg bones to improve leg stability during leaping -faunivorous: small insects, snakes, and lizards 2)catarhines including humans and apes Catarhinni's consist of cercopethicoidea, hylobatidae, and hominidae Cercopithecoidea's are mainly distinguished from hylobatidae, and hominidae due to their narrow long noses and bilophodant molars Hominidae and hylobatidae have bunodont molars Bunodont vs bilophodont molars >bunodont molars are chatacteristic of animals that eat diff kinds of foods w different physical consistencies (fruits, flowers, grains, and meat) whereas bilophodont molars are assoc'd with the chewing of leafy plant materials (cercopithecoidea) -hominidae and hylobatidae LACK A TAIL, have LARGER brains and body size THAN CERCOPITHECOIDS 3)platyrhines including new world monkeys (ceboidea) >New World Monkeys >characterized mainly of having flat noses, which is why they are called platyrrhine which means flat nose & side facing nostrils >they are named New World Monkeys bc they are found only in Central & South America >although all platyrrhines have tails only a select number of them have prehensile tails (only the atelidae) >all live in social groups Cercopithecoidea -example of sexual selectoin which is mate choice -for them, females choose mates based on behavioural or physical characteristics >females good at doing this; will increase their fitness so w/ each subsequent generation, they will get pickier because of this particular nose Hominidae -all large bodied apes are highly sexually dimorphic in body size and dentition, w males being larger than females -orangutans, gorillas, and chimps are less suspensory than GIBBONS, meaning that these large bodied apes are not acrobatic swingers thru the forest , instead employ quadrumanous climbing, meaning they use three to four limbs to move carefully and methodically through the forest the forest On the ground, large bodied apes use quadrupedal walking and running however gorillas and chimps employ a unique hand position called knuckle-walking, instead of supporting their body weight on their palms, they support themselves in the dorsal surfaces of their curled up fingers Gorillas and chimps are terrestrial knuckle walkers, making it evident that ancestor was a knuckle walker as well Gorillas live in single male groups BODY SIZE If an animal doubles in size (i.e., double in length, breadth, and width), then the area would be four times larger and the volume would be eight times greater Small animals lose more energy, in the form of heat (energy) loss to the environment than a large animal >place one large and one small ice cube in a sink full of warm water. As you will see and may have already deduced, the small ice cube melts first. The reasons for this are more complex than they appear: specifically, the small ice cube has a greater proportion of its internal volume expos
More Less

Related notes for ANTB14H3

Log In


Don't have an account?

Join OneClass

Access over 10 million pages of study
documents for 1.3 million courses.

Sign up

Join to view


By registering, I agree to the Terms and Privacy Policies
Already have an account?
Just a few more details

So we can recommend you notes for your school.

Reset Password

Please enter below the email address you registered with and we will send you a link to reset your password.

Add your courses

Get notes from the top students in your class.