#4 Flashcards
Are all NWM arboreal?
Yes
OWM distribution
Africa and Asia
what is social attraction?
individuals seeking out proximity to each other outside of environmental stimuli
(more than a response to predation, to localized food resources)
What are some examples of social mammals?
Social carnivores, social canids, Pachyderms
Social Mammal: Lions
- females have complex social relationships
- no dominance hierarchy
- strong between-group competition
- Cooperative hunting, raising of young and defense against male infanticide
Social mammals: Spotted Hyenas
- social life similar to cercopithecines
- extensive coalitions between females (allies that they can rely on when in conflict)
- Despotic (strict) hierarchy among females
- strong dominance hierarchy (top ranking has highest reproductive success)
- between-group conflict (explains extensive coalition between females)
Social Mammals: African Wild Dogs
- tightly bound social group led by dominant male and female
- communal pup raising and feeding (everyone plays a part in raising it)
- tight social bonds associated with spreading of diseases and decline of wild dog numbers
Social Mammal: African Elephants
- female philopatric (females stay together for life)
- males live alone or in loose association
- matrilineal
- oldest female (highest rank, lead group)
- age matriarch is directly correlated with reproductive success
what characteristics are unique to primates?
- differentiated within-group relationships (hierarchy)
- marked social boundaries
- kin-based social relationships (nepotism)
- use of allies and coalitions in some species
What are 2 Key costs of group living?
- Intra-group competition (within the group)
2. Increased vulnerability to infectious diseases
What are benefits to group living?
- Resource Defence Hypothesis
- being in a group improves access to resources
- Large VS small group advantage (larger the group size the more encounters you win) - Predation Defence Hypothesis
-better protection from predators
(A) Collective detection (more eyes and ears to detect)
(B) Dilution effects (each individual has a less of a chance of being caught)
(C) Deterrence - Mates are readily available
- More eyes looking for food
What is Resource Defence Hypothesis?
- Benefit to group living
- being in a group improves access to resources
- large VS small group advantage (larger the group size the more encounters you win)
What is Predation Defence Hypothesis?
- Benefit to group living
-better protection from predators
(A) Collective detection (more eyes and ears to detect)
(B) Dilution effects (each individual has a less of a chance of being caught)
(C) Deterrence
Resource Defence
large groups usually have better access to food patches
Predation Defence
terrestrial primates tend to live in larger groups than arboreal ones
-some primate species adjust group size to the risk of predation
What is male-biased Dispersal?
When the male leaves his natal group
What is Female-biased dispersal?
when the female leaves her natal group
Male-biased Dispersal
- males leave natal group
- females philopatric / remain in natal group
- SOCIAL STRUCTURE: matrilineal (female-bonded)
Female-biased dispersal
- female leaves natal group
- males philopatric / remain in natal group
- SOCIAL STRUCTURE: patrilineal, (non-female bonded)
Both sexes dispersal
- both sexes can leave the natal group
- neither sex is a resident in the natal group
- SOCIAL STRUCTURE: neither sex is bonded, (non-female bonded)
what types of interactions show predominant/important relationships between primats?
Affiliation (grooming; sitting in proximity)
Agnostic Support (you help an ally in conflict, they help you)
Minimal Aggression (tolerance of proximity when feeding)
What are Sociographs?
-used to show the direction and intensity of a social relationship
What is a social system?
-the individuals that mate within a social system
Social Organization
- Cohesive
- Fission-fusion
- Multi-level societies
at is fission-fusion?
fission –> animals separate to feed
fusion –> animals come back together to sleep
Social System (Unit)
- solitary
- pair-bonded –> living together
- uni-female, multi-male
- uni-male, multi-female OR multi-male multi-female
Social Structure
- patrilineal, non-female bonded
- matrilineal, female-bonded
- non-female bonded, neither sex bonded (unrelated)
Mating System (Unit)
Monogamous –> one male, one female
Polygamous –> multi-male, multi-female
Polyandrous –> uni-female, multi-male
Polygynous –> one-male, multi-female
Social System : Solitary
Social Structure: neither sex bonded; related females are overlapping ranges; adult male territory overlaps with one or more adult females
Mating System: Polygyny (Dispersed)
EXAMPLE: Orangutan
Social System: Pair-Bonded
Social Structure: neither sex bonded (both dispersed / do not live together)
Mating System: Monogamous (~25%); extra-group copulations (polygamous mating)
Social System: Uni-female, Multi-male
Social Structure: (2 Scenarios)
- neither sex bonded (both sexes disperse)
- female-bonded
Mating System: (2 Scenarios)
- POLYANDRY (one female, multiple males)
- COOPERATIVE POLYANDRY (closely related females, one reproduces and the others female help raise the offspring)
Why don’t subordinate females leave in cooperative polyandry?
- Dispersal costs are HIGH
- predation, lack of territory, unfamiliar food sources - Inclusive fitness:
- helpers are related to the dominant female (by helping they improve their RS)
Male Callitrichids
-high paternal investment and care
Social System: Uni-male, Multi-female
Social Structure: neither sex or female bonded
Mating Structure: Polygynous (males monopolize access to females and mate with many females); females mate with one male
-intense sexual dimorphism
Social system: Multi-Male, Multi-Female
Social Structure: female-bonded OR non-female bonded (neither sex bonded)
Mating System: Polygamous (both sexes mate with 2 or more partners)
EXAMPLE: Chimps, Savanna Baboons
Cohesive Groups:
- Stay together all the time
- maintain visual and vocal contact with each other
Fission-Fusion Groups
- Fluid structure
- Animals feed in parties of differing composition or alone
- Groups often fusions to sleep (they sleep together)
Multi-Level Societies
- most complex type of social organization
- 3 levels of organization
1. Basic Unit: Uni-male, Multi-female
2. The Band: 2-4 units that eat and sleep together
3. The Herd: Several bands make up a herd – a temporary aggregation at a sleeping site or large foraging areas (can # in the hundreds)
