1. Primate Behavioral Ecology

2. Primate Behavioral Ecology
The study of primate behavior from both an ecological and evolutionary perspective.

3. Key terms when discussing Primate Behavioral Ecology:
Home Range: The size of the geographic area that is occupied and used by a social group. A group’s territory.

4. Key terms when studying primate social behavior
Affiliative: strong friendly social bonds
Agonistic: unfriendly behaviors, often aggressive.
Sociobiology: another name for Primate Behavioral Ecology.

5. Key terms when discussing Primate Behavioral Ecology:
Ethology: studying creatures in the wild under natural conditions.
Primatology and Primatologist: the study of Primates/someone who studies primates

6. Key Players: Primatologists
Jane Goodall: much of what we know about chimpanzee behavior comes from almost 50 years at Gombe Stream National Park in Tanzania, led by Goodall. Some of the most famous chimpanzees ever studied were at Gombe (David Greybeard, Pip, Flint, etc)

7. Key Players: Primatologists
Dian Fossey: Was a zoologist who studied mountain gorillas in Rwanda for 18 years. Active in the conservation of gorillas and the protection of their habitat. She was murdered in 1985, the case remains open.

8. Key Players: Primatologists
Birute Galdikas: Studies orangutans in the Indonian island of Borneo. Very active in habitat conservation. Today she and her staff at her research station in Borneo take in orphaned orangutans and raise them until they can be rereleased into the wild.

9. Key Players: Primatologists
Richard Wranghum: Studies chimpanzees as well as evolution. As a graduate student he studied under Jane Goodall (he also helped Birute Galdikas set up her research station in Borneo). Currently, he teaches physical anthropology at Harvard.

10. Key Players: Primatologists
Frans de Waal: Dutch primatologist and ethnologist. Largest captive chimpanzee colony (at the Arnhem Zoo). Famous for studying the “make love not war” Bonobos. Studies primate bonding and competition.

11. Social Group Types 1 male /1 female 1 male/multi-female (very common)
Multi-male/ 1 female
Multi-male/multi-female (very common)
(Dispersal: when an individual leaves its birth group to live in another group or alone.)

12. Reproduction Strategies
Life History Theory: How the characteristic’s of an organism’s life cycle affects reproduction. Looks at trade offs between energy expended for numbers and fitness of offspring.
Reproduction strategy: primates have slow life histories and invest a lot of time and energy into the care of offspring.

13. Reproduction Strategies
Estrus: In non-human primates, the time of female fertility, or the signals indicating fertility. “In heat.”

14. Reproduction Strategies
Primates have a strong, long lasting bond with their mothers that goes beyond just the need for food and protection

15. Reproduction Strategies
In many monogamous primate species there is a high level of adult males helping in the care of infants.
Having offspring means an increase in genetic fitness. Therefore in polygamous species, the males have less interaction with infants.

16. Reproduction Strategies
Alloparenting: individuals who take care of an infant but is not that infant’s biological parent.

17. Reproduction Strategies
Infanticide: The killing of an infant (by an adult male).
Most famously observed (by Sarah Hrdy) in langurs.
Paternity Certainty: may not have absolute paternity certainty but primate species who are more monogamous often act as if they do.

18. Key terms when studying primate social behavior
Grooming: For primates grooming is a form of reassurance and also acts as a means of communication.

19. Key terms when studying primate social behavior
Sexual dimorphism: the difference in body size between males and females of the same species.
Example: Male orangutans have big fleshy cheek pads, throat sacs, large canine teeth, and lots of bulk! (Can have cases of arrested development).

20. Key terms when studying primate social behavior
Altruistic: Behaviors benefiting others without regard for one’s own needs or safety.
Kin selection: altruistic behaviors selected when they are in favor of biological relatives.
Inclusive fitness: biological fitness is measured by the success of one’s genes whether possessed by the individual or by the relatives.

21. Key terms when studying primate social behavior
Dominance hierarchy: the ranking system within a group which specifies which individuals are dominant in social behaviors.

22. The Importance of Food and Foraging
Foraging: looking for, handling and eating food.
Foraging can occupy more than 50% of a primate’s waking hours.
Seasonal differences in food can dictate seasonal behavior in a primate’s foraging patterns.

23. The Importance of Food and Foraging
Nearly all aspects of primate social organization are affected by the distribution of their food in time and space.
Food is especially important to female primates because of the metabolic costs associated with gestation and especially lactation.

24. Primate communication
Tactile (grooming, playing, fighting)
Visual (facial expressions)
Olfactory (smells)
Vocal

25. Case Studies: Howler Monkeys
11 species, in the genus Aloutta.
Mexico, Central and South America
New World monkey
Larger than average hyoid bone

26. Case Studies: Howler Monkeys
Sexual dimorphism: Males are larger than females. Adult Howlers weigh between 13 and 18lbs.
Social organization: groups of 10 to 15 individuals.

27. Case Studies: Howler Monkeys
Howler monkeys have a home range that is more of a territory (where they are at that time, so less of an area with set boundaries).
Howl: for defending territory, for defending food, might also be a substitute for active fighting.

28. Case Studies: Gorillas
Largest living primate
Mostly terrestrial (due to their size)
Habitat: equatorial African forests
Two species of gorilla
Diet: leaves and fruit, most of the day is spent eating, due to their large body size.

29. Case Studies: Gorillas
Sexual dimorphism: Males are larger than females (weighing about 350lbs). Adult males also have larger canine teeth and a crest of bone on the top of their skulls. Mature males have silvery gray hair on their back, giving them the name silverbacks.

30. Case Studies: Gorillas
Knuckle walking: all four limbs on the ground weight of the arms and upper body resting on the knuckles of the hands. This form of movement is also used by chimps and bonobos.

31. Case Studies: Gorillas
Social organization: Gorillas live in small groups of about 8 to 10 individuals. This includes one silverback male, adult females and their immature offspring.
Communication: vocals and facial expressions, and even sign language (in captivity).

32. Case Studies: Baboons There are 5 distinguishable species of baboons.
They live in the African woodlands, desert, and savanna.
Groups range anywhere from 20 to 200 individuals.
Hamadryas Baboon/ Olive Baboon

33. Case Studies: Baboons
Sexual dimorphism: Males are typically twice the size of females and have very large canines.
The male who is the most aggressive, largest, and smartest becomes the dominant male of the group.

34. Case Studies: Baboons In general males are dominant over females.
The social structure of the Olive Baboons of equatorial Africa is based on a network of social alliances, including friendships.

35. Case Studies: Baboons
They have a complex social organization and their savanna habitat makes them of particular interest to anthropologists, because it was an important habitat for our early human ancestors.

36. Case Studies: Chimpanzees
Dominance hierarchy: males typically dominant over females. Males compete to achieve the highest position. BUT there is no dictatorship, chimp society marked by cooperation and mutual concern.

37. Case Studies: Chimpanzees
Social interactions:
one the most important is grooming. Acts as social cohesion and also as a form of submission.
Facial expressions and vocalizations are very important social interactions in chimps as well, and much can be learned from these.

38. Full open grin: often used by high ranking chimp when in close proximity with a subordinate

39. Pant-hoot: each individual’s pant hoot is a little different
Pant-hoot: each individual’s pant hoot is a little different. Can be solo or a group pant-hoot, used most often as a greeting, or when foraging

40. Case Studies: Chimpanzees
Mother infant bond is long-lived and very important, it has lasting effect on a chimp’s life. Poor maternal care results in a female chimp being a poor mother herself.
Alloparenting in chimps: siblings often help in “raising” infants. This creates strong family bonds, adult brothers will even help one another in their competition for dominance.

41. Case Studies: Chimpanzees
Group identity: groups are fluid, individuals will leave a group and others will enter it, but there is still strong group identity and sense of group territory.
Diet: wide range of food sources (fruit, leaves, meat). Hunting of small antelopes, pigs, and monkeys – even small baboons-has been observed. Meat is shared amongst the group.

42. Case Studies: Chimpanzees
Tools: at Gombe, Goodall observed chimps using a long reed as a tool to extract termites from their mound to eat. Other groups have been seen using hammerstones to crack open nuts.

43. Case Studies: Bonobos The “peaceful” ape
Females may be dominant over males.
Share food easily
Never have been observed killing another of their own species (unlike chimps).
Use sexual behaviors as a means of group cohesion, and the signs of estrus are almost always present in bonobo females.

44. Case Studies: Bonobos
Closely related to chimps (separated about 930,000 years).
Habitat: lowland forests of DRC
Used to be known as “pigmy chimpanzees” though the are the same size, just leaner, with slightly smaller skulls.
Walk bipedally more often than chimps.

45. Case Studies: Bonobos
Diet: like chimps wide range of food, also like chimps, bonobos hunt but there is no evidence of cooperative hunting. Females also hunt, which is different from chimpanzees.

46. Case Studies: Bonobos
Tools: Bonobos use tools, but they have never been observed using them to acquire food.

47. Case Studies: Orangutans
In Indonesian “orang” means “person” and “utan” is a derivative of “hutan” meaning “forest.” Therefore, Orangutan literally means “person of the forest”
Habitat: Only found in S.E. Asia: Borneo and Sumatra

48. Case Studies: Orangutans
Sexual dimorphism: Males are much larger than females (roughly 2Xs larger). Males weigh about 190lbs, females about 86lbs.
Social organization: males will have dominance over territory where several females live, but orangutans are pretty solitary.

49. Case Studies: Orangutans
It used to be thought that they were almost entirely arboreal, but new studies have shown they might be more terrestrial then once believed.
Orangutans have incredible strength.

50. Case Studies: Orangutans
Infant care: infants will hold tight to their mothers for the first 4-6 years of life.