Primates

## Primate Communication

- Communication: Process by which the behavior of one animal affects the behavior of another

- Olfactory, non-vocal, vocal

- Maintenance of social cohesion; better ability to effectively cope with environmental stresses

- Is the metal capacity to learn a language a unique human trait?

- Language:

- Vocabulary

- Grammar

- Gardner's: Taught ASL (American Sign Language) to Washoe in 1966 (Wild female captured at the age of 11 months)

- Created the environment where language learning is possible

- Created situations constantly where language was useful; emulated stimuli

- 7 months: Gardner's concluded she was using sentences with correct grammar

- If used word 3 times, went on a list of possible words; if then used correctly 15 days in a row, considered to be learned

- 36 months: 85 signs; 51 months: 132 signs

- Rumbaugh's Yerkes Primate Center

- Created computer based language

- Less flexible -> Limited ability to innovate

- Terrance and Nim Chimsky (Chimp)

- Concluded what was originally language was seen as subtle cueing

- 40% of the time Nim repeated what the observer signed

- Both felt that they did not construct true sentences

- Criticisms

- Rapid turnover of 60 different trainers

- Raised in a socially sterile environment

- 2 three hour training sessions 5 days per week; otherwise left alonee

- Positive Results (Washoe)

- 1. Examples where no subtle cueing

- Double blind tests

- Sign to herself after learning new sign

- Sign to herself while looking at magazines

- Sign to herself before she acted

- 2. Good understanding of word order

- 3. New words

- a) Swan = water bird

- b) Alka Seltzer = listen drink

- c) Brazil Nut = rock berry

- d) Cucumber = green banana

- 4. Loulis: Taught some signs; learned others on his own; 80 signs

- 5. Chimps at CWU regularly use sign language with humans and with each other

- 6. Sherman and Austin

- 7. Kanzi

- Left planum temporale: Larger in humans but not in chimps

- FOXP2 Gene Mutation

- Regulator gene

- 3 codon difference between humans and chimps due to a mutation 200,000 - 120,000 years ago

- Conclusions

- Chimps may have the ability to learn the rudimentary basics of language (maximum of a human 3 year old)

- Some capacity for language (minimally vocabulary) semes to part of primate heritage

### Savannah Baboons

- Dinural

- Troop under direction of alpha male;

- Lives in sleeping groves

- Moves between groves at an interval

- Sexual dimorphism in body and canine size

- Dominant males: Leadership, defense

- Alliances

- Very rare; only when a Baboon gets to the top, they may form alliances to maintain their high rank

- Males challenge each other on their way to become the alpha

- Female dominance hierarchy tends to be more stable: Males must join new troop at adulthood

- Strict dominance hierarchy; dominant more likely to mate with ovulating females

- Diet: Omnivorous but primarily consume vegetables; also eat fruits, insects, small game

- Disease Avoidance Behaviors

- Passes down information from generation to generation

- New beneficial behaviors learned in the past are passed down

- Observed in Amboseli National Park, Kenya

- Troops that follow certain behaviors prosper; others who don't will die out and thus the behavior will propagate

- Disease vectors:

- Intentional parasites and helminths (worms) which are passed from individual to individual by contact with feces

- Never defecate near water sources

- Defecate in sleeping groves but larvae do not hatch for 2-4 days and live only for about 9 days

- Each troop uses 15-20 sleeping groves

- Average f 2 days

- Average of 9 days before they return to the same sleeping grove

- Ticks and fleas

- More ticks and fleas -> Higher frequency of grooming

- Less dominant generally initiate grooming but the more dominant must reciprocate

- Higher grooming time -> Higher fitness

### Gorilla

- Subspecies

- Western lowland gorilla; = 100,000

- Eastern lowland gorilla; = 12,00

- Mountain gorilla = 250-300

- Shy; habituation

- Social groups of 2-30 animals: 1 silverback, adult females, younger adult males; young stable groups

- Minimal territoriality

- Strict dominance hierarchy

- Vegetarians; up to 70 pounds/day

- Takes a long time to eat and digest all the food

- Pronounced sexual dimorphism; males 300-400 pounds

- No tool use

- Grooming, vocal communication, and play are infrequent (relative to other hominoids)

- Morphology of brachiation but generally knucklewalk

- Humans are their own predator

### Orangutan

- Located in Indonesia

- Less than 20,00 but estimated 315,000 in 1900

- Relatively little tool use in the wild; tool use in captivity

### Bonobo

- Bonobo = Pan paniscus = Pygmy chimp

- Estimated 30,000-50,000 in Congo River Basin; Kano; extinct within 10 years at present rate of decrease

- Bonobo/chimp split about 2.0mya

- Males about 95lbs and females 75lbs

- Forage primarily in trees (spends most of their time there)

- Rarely hunt animals for meat

- Females leave birth troop and are troop leaders

- Seen by us to be much less violent than champs

- They spend most of their time in trees and thus they were hard to observe

- New studies show bonobos are 3 times as many aggressive interactions as chimps

- But

- Chimp males were very aggressive towards females while bonobos are not

- Chimp male aggression can result in death and that has never ben observed in bonobos

- Bonobo troops in neighboring territories interact peacefully; not so with chimps

### Pan Troglodytes/Chimpanzee

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