Primate Ecology

Question 1

What is ecology?

Answer 1

Interactions between organisms and their environment
physical environment = habitat
biological environment = interaction with other organisms

Question 2

What are the two main concerns for primates trying to make a living?

Answer 2

1. How and what to eat
2. How to avoid being eaten
   These two concerns influence sociality

Question 3

What does total energy required depend on?

Answer 3

1. Basal Metabolism
2. Active Metabolism
3. Growth and growth rate
4. Reproductive effort

Question 4

What is basal metabolism?

Answer 4

rate at which an animal expends energy at rest for basic body maintenance
- Larger animals have higher absolute BMR, but relatively lower BMR per unit body weight

Question 5

What is active metabolic rate?

Answer 5

The energy require for daily activities above the baseline (for locomotion, digestion). Depends on size of animal and how far/fast it travels

Question 6

What is growth rate?

Answer 6

Building new tissues requires energy beyond BMR and AMR
- infants/juveniles have higher energy requirements than predicted for their size
- More energy cost for primates because of the size of our brains

Question 7

What is reproductive effort?

Answer 7

For females, there is an additional cost for reproduction. You need more calories (energy) during pregnancy and lactation

Question 8

What are nutritional requirements for primates?

Answer 8

Diet must satisfy energy requirements and nutrients they cannot synthesize themselves.
- Protein/amino acids for growth, reproduction, and normal bodily functions
- Fats, oils, and carbs provide energy
- Vitamins and minerals important for specific physiological functions

Question 9

What should nutritional requirements prevent?

Answer 9

Minimize dangerous toxins

Question 10

What are secondary compounds?

Answer 10

Plant defenses that prevent primates from eating them.
Alkaloids: disrupt normal cell processes
Tannins: reduce digestability of plants

Question 11

Where is secondary compound concentration highest?

Answer 11

Highest in mature leaves and seeds. Lower in fruits, flowers, and new leaves

Question 12

What are frugivores?

Answer 12

Fruit eaters

Question 13

What are folivores?

Answer 13

Leaf eaters. They eat more young leaves (easily digestable). Also have a higher concentration of protein and sugars.

Question 14

What are insectivores?

Answer 14

Insect eaters

Question 15

What else do primates eat?

Answer 15

Grasses, tubers, corms, gum, vertebrates, bark, fungus, soil

Question 16

What is the first primate generalization?

Answer 16

Most primates rely on one food type that is high in protein and one high in carbs

Question 17

What do most strepsirrhines use for carbs and protein?

Answer 17

Insects for protein and gum/fruit for carbs

Question 18

What do most haplorrhines use for carbs and protein?

Answer 18

Insects/young leaves for protein and fruit for carbs

Question 19

Why do some primates not directly drink water?

Answer 19

Usually, frugivores or other primates who eat food with a large quantity of water don’t have to directly drink water

Question 20

What is the second primate generalization?

Answer 20

Primates rely more heavily on some types of foods than on others (based on preferance.
- This gives us the food terms

Question 21

Where are primate diets reflected?

Answer 21

Tooth and gut morphology
- insectivores have sharp teeth
- folivores have sheery crests
- we have flat molars

Question 22

Based on food preference, which primates are bigger?

Answer 22

Folivores > frugivores > folivores
- BMR scales with body size
- Smaller animals require small but high quality food
- Larger animals are not constrained by quality of food, they bulk feed (folivores)

Question 23

Does food availability vary?

Answer 23

It varies based on space and time. Food is highly seasonal.

Question 24

What happens when there is a scarcity of food?

Answer 24

Primates may switch to lower quality diets (unripe fruit, mature leaves), reducing their energy expenditures, or on food they usually don’t prefer.

Question 25

What is a primate range?

Answer 25

The geographical area in which a group (not a species) can be found
Home range: total area used by the group
Daily range: area used by an individual on a daily basis

Question 26

What influences territoriality?

Answer 26

Varies among species and sometimes ranges overlap. Food distribution influences territoriality

Question 27

What happens when food resources are evenly distrubuted vs clumpy?

Answer 27

hard to protect evenly distributed resource. Clumpy resoureces are easier to defend

Question 28

What are the costs and benefits to territoriality?

Answer 28

Costs: constant vigilance, advertising presence, engage defense (getting hurt while fighting)
Benefits: prevent outsiders are exploiting limited resources

Question 29

When do territoriality benefits outweigh costs?

Answer 29

Depends on the kinds of resources and their impact on fitness. Females need for access to food and males need access to females.

Question 30

What two functions does territoriality serve?

Answer 30

Resource defense (food, nesting sites) and mate defense

Question 31

What are factors that increase predation risk?

Answer 31

Being terrestrial or a smaller group size

Question 32

How do primates avoid predators?

Answer 32

Alarm calls, swarm and attack the predator, associate with other primate species, lice and forage in groups

Question 33

Why does sociality prevent predation?

Answer 33

Detection: more eyes on the lookout
Deterrence: swarming/mobbing predators
Dilution: lower chance of being eaten in a group
- You don’t have to be faster than the predator, just faster than your friend

Question 34

What are the costs and benefits of sociality?

Answer 34

Benefits: resource control (intergroup competition), predator avoidance, more access to mates
Costs: feeding/mate competition, intragroup competition, disease risk, incest/infanticide, cuckholdery

Question 35

What are polyspecific associations?

Answer 35

Different species travel and forage together for extended periods of time
- greater predator protection without increases competition for food/mates
- foraging benefits: mutual defense, finding food resources, taking leftovers from others (scrounging)

Question 36

What is fission?

Answer 36

It is temporary to reduce intraspecific competition. Big groups split into two groups