Hominoids and Primate behavior - WordPress.com and Primate behavior Part 1 from Monday 1. Today ......
Transcript of Hominoids and Primate behavior - WordPress.com and Primate behavior Part 1 from Monday 1. Today ......
Hominoids and Primate behaviorPart 1 from Monday
1
Today*Quizzes and grades update
*Midterm info
*Look at the apes
*Primate behavior
*Origins
2
3
Hominoids - the apes and humansCompared to the other haplorhines, hominoids:
Location: Asia and Africa-larger body size-lack a tail-shoulders adapted for suspensory behavior-more complex behavior-increased period of infant dependency
4
Gibbons and Siamangs
5
Location: Asia
Morphology: traits reflecting adaptation to brachiation
Behavior: territorial; social unit = adult male and female and their offspring
Orangutans
6
Location: Islands of Sumatra and Borneo
Morphology: sexual dimorphism between male/female body size
Diet: frugivorous
Behavior: mostly solitary
Gorillas
7
Location: West/east equatorial Africa
Morphology: largest living primates; also sexual dimorphism between male/female body size
Diet: vegetarian
Behavior: Groups with one or two adult silver back males, several females and offspring
Chimpanzees
8
Location: equatorial Africa
Morphology: smaller body size; less pronounced sexual dimorphism
Diet: varied diet (fruits, leaves, and hunting small animals)
Behavior: live in large communities; complex social interactions emphasizing male-male bonds
Bonobos
9
Location: Near Zaire River
Morphology: similar body size to chimpanzees
Diet: varied diet
Behavior: fluid communities; complex social interactions emphasizing male-female bonds; copulate throughout female estrous cycle
10
Humans
11
Location: Everywhere
Morphology: adaptations of the pelvis, leg, and foot enable habitual bipedalism
Diet: generally omnivorous
Behavior: Completely dependent on culture
Primate social unitBasic primate social unit: female and her infant(s)
Note: nonhuman primates learn their caregiving behavior-monkeys/apes in captivity without parental contact do not know how to care for newborn infants
12
How primatologists study behaviorBehavior: anything that involves acting in response to stimuli-not necessarily done consciously-may/may not be deliberate
Behavioral ecologyAll interconnected biological components* within an ecosystem evolved together
*components: animals, plants, microorganisms, etc.)
- the product of complex interactions between genetic and environmental factors
Social structure - important to us
13
How primatologists study behaviorSocial structure - the composition, size, and sex ratio of a group-the result of natural selection
-large impact on individual and social interactions
Influences on social structure:Body sizeBasal metabolic rateDietDistribution of resourcesPredationActivity patterns
14
How primatologists study behaviorSocial structure - the composition, size, and sex ratio of a group-the result of natural selection
-large impact on individual and social interactions
Influences on social structure:*Body size-body heat lost at surface -larger animals retain heat more efficiently
*Basal Metabolic RateMetabolism - at rest, the rate at which the body uses energy to maintain bodily functions -closely tied with body size
15
Influences on social structure*Diet - likely evolved with body size and BMR-diet relates to behavior in terms of benefits measured against calories expended obtaining those calories
*Distribution of resources-feeding behavior determined by distribution of food resources and ease of accessE.g., matrilines (one male multiple female) break up into smaller groups while feeding
16
Predation-behaviors in response to predatorsE.g., if high predation, smaller-bodied animals are likely to form larger communities
Life HistoriesLife history traits - characteristics or developmental stages a given species features/undergoes
E.g., shorter life histories are often more advantageous in marginal/unpredictable habitats (rapid reproduction)
...while longer-living animals are better suited to stable environmental conditions
17
Influences on social structure
1. Primate grouping patterns1. Single female and offspring - Basic social unit (e.g., orangutans)
2. Monogamous family group - rare in nonhuman primates
3. Polyandrous - single female: multiple male (e.g., marmosets)
4. Single male and multiple female - single male: multiple female (e.g., gorillas)
5. Multiple males and multiple females - no stable bonds (e.g., baboons)
6. Fission-fusion - size and composition change relative to activities and patterns (e.g., chimpanzees)
18
Reproductive strategiesBehavior favored by natural selection to increase an individual's reproductive success
K-selection - an adaptive strategy with fewer offspring and increased parental investment
E.g., birds, wolves, elephants
r-selection - more offspring coupled with less parental investment
E.g., mice
Primates are K-selected and the mother plays a larger role in raising offspring
19
Primate reproductive strategiesPrimates are K-selected and the mother plays a larger role in raising offspring
Females - strategy: maximize available resources given energetic demands of being female
Males - strategy: produce as many offspring as possible
20