Resources Flashcards
Food Quality
High quality food, such as fruit, is rare and spread out. Low quality foods, foliage, is everywhere are easily acquired.
Patch Variability
Fruits and flowers are highly seasonal, whereas foliage is constantly renewed.
Scramble Competition
No other individual is stopping one from entering or feeding in a food patch but is there more advantage to going elsewhere? On average everyone does as well as each other.
Contest Competition
High quality patches are being defended so does the risk of fighting worth the benefit of gaining access to the patch. If one is excluded from all patches they must risk predation to find food.
Harper 1982. Ideal Free Ducks
In area 1 there is more food but also more ducks. Area 2 there are less ducks but also less food. How should they be distributed?
Ideal Despotic Distribution Theory
This predicts that the quality of a habitat controlled by territorial animals should vary depending on their competitive ability and the availability of resources. It makes more sense to to travel to many low quality patches than to control a low quality patch since the high quality patches will be controlled by ruling males.
Benefits and Costs of Defence
Cost worthy to control a large area with not much food init as one would spend more calories patrolling then on what they gain from the food in the area. whereas if theres lots of food a balance of defence, patrolling and feeding that needs to work out to make it worth it.
Energy rich foods
Fruit, seeds, flowers and gum. CHO lipids means they have lots of energy as well as vitamins, minerals and water.
Protein rich foods
Leaves: energy from cellulose but young vs old, changes in fibre:protein ratio.
Kay’s Threshold (1984)
Larger primates eat leaves whereas smaller ones on average, eat insects. Although there are many expectations, such as mouse lemurs eat fruit.
Plant’s Perseptive
If an animal eats your leaves it hinders your ability to make food for yourself, therefore they have defences such as hairs on leaves, strings or bark. Tannins are indigestible and alkaloids are toxins. Therefore, plants want their fruit to be eaten as it benefits the by getting their seeds to disperse.
Primate response to plant defences
- Teeth, jaws, digestion and tool use.
- Dietary Switching
- Geophagy (soul eating)
- Selectivity
Fallback Foods
Foods to be eaten just to get by when all other food is gone.
Ranging behaviour : Day range
Distance traveled per day (measured in metres)
Ranging behaviour : Home range
Area encompassed by all day ranges (measured in hectares)
Social Foraging
Vast amounts of primates live in stable groups and eat together too. Repeated interactions, dominant- subordinate interactions.
Food Distribution: Low quality
Low quality, even distribution
- Little reward in any one item
- But food is everywhere
Food Distribution: High quality, Small patches
High quality, small patches
- Little reward in each patch
- Quickly depleted
- Food for 1
Food Distribution: High quality, Medium patches
- Sizeable reward in each patch
- More slowly depleted
- Food for some but not for all
Food Distribution: High quality, Large patches
- High reward
- Very slow depletion
- Food for all
Within group contest
- Food distribution defendable and worth defendable (medium-sized patches)
- Dominant individuals monopolise resources (eg. via aggression and avoidance)
- Subordinates excluded from a resource, or may have to go to less profitable areas.
Within group competition consequences
- More aggressive/dominant = higher feeding success
- Decrease in energy gain with lower dominance rank
Between group contest
- Large food patches defended against other groups
- Dominant groups displace subordinate groups
- Subordinate groups feed in less profitable areas/resources
Between Group Contest Consequence
- Exclusion of subordinate (usually smaller) groups high quality resources
- Increase in energy gain with group size
