Lecture 12: Behavioral Ecology

Question 1

Animals need 3 critical needs

Answer 1

1. Obtaining Food
2. Finding mates
3. Avoiding predators

Question 2

Behavior

Answer 2

Behaviors can be genetic or learned
Behaviors often a product of both genes and environment

Question 3

Behavioral decisions often

Answer 3

balance costs and benefits in the 3 critical needs/ interests for animals

Question 4

Proximate Cause

Answer 4

Explanation of a behavior for a particular individual due to events occurring over their lifetime

Question 5

Ultimate Cause

Answer 5

Evolutionary and historical reasons for a particular behavior

Question 6

Example of how Behavior can be genetic with Cockroach

Answer 6

Cockroach traps set with glucose
Over time, the population exposed to these traps evolved behavior of avoiding glucose (even when not in a trap_
In comparison, wild type cockroaches still love it

Question 7

How can behavior be learned?

Answer 7

Learned and passed through families
Ex. Dolphins use sponge to help protect nose when searching food

Question 8

Behavioral ecology

Answer 8

study of the ecological and evolutionary basis of behavior

Question 9

Foraging behavior

Answer 9

weighing costs and benefits in obtaining food

Question 10

Optimal foraging theory

Answer 10

model that predicts how animals search for food by maximizing energy gain while minimizing costs

P= E/t
P=profitability
E= net energy value of food
t= time invested in obtaining and processing the food

Question 11

What do species have to think about when favoring prey?

Answer 11

Elements that influence profitability: Net energy and Time invested

Question 12

Elements that influence profitability via net energy and time invested are

Answer 12

Net energy:
+ energy obtained
- energy spent finding the food
- energy spent handling the food

Time invested:
+ time invested in finding
+ handling the food

Question 13

Each patch has worms. More time spend in a patch the harder it is to find the next worm. How long should be a bird spend in a patch before giving up and going to a fresh patch?

Answer 13

Profitability of a patch may diminish over time

Stay too short: low profitability
Stay too long: low profitability
Find maximize the slope E/t for maximize profitability for optimal giving up time, time to look for next patch

Question 14

Make a testable hypothesis for Optimal Foraging model/theory: Looking at if travel time increases, how does that change the ideal amount of time spent in a patch

Answer 14

Vary spacing between patches
Offer starlings worms on tables located at different distances from their nests
Increase in travel time, Increase in optimal giving up time

Question 15

Trading off food for survival can

Answer 15

optimizing fitness
Ex. Elk have to balance eating how much grass in also surviving from predation from wolves
Elks more likely to be around in grassland when wolves are not around and are less likely to be around grassland and go to conifer forest when wolves arrive

Question 16

Anti predator behaviors

Answer 16

Direct selective pressure for anti predator behavior to increase fitness and survival
Ex. Eyespots on a moth appear to be bigger than they are
Sealions sleep with one eye open; half of brain alert to keep eye out for predators
Springbok stotting behavior; tries to intimidate a lion

Question 17

How effective are eyespots for predator deterrence?

Answer 17

Many different types of animals that have coloring that might be considered to be eyespots
Taking an animal (ex. cattle) that does not have eyespots and adding artificial eyespots to see if it will reduce predation
Look at cattle with 3 different treatments: eyes, X’s, and nothing
Outcome: Artificial eyespots decrease predation on cattle from ambush predators
Supports hypothesis that eyespots are effective
Evidence also supports alternative explanations that novel or rarely encountered conspicuous features may be intimating to predators

Question 18

How good was control for experiment testing effectiveness for eyespots for predator deterrence?

Answer 18

Could have been better control with equal amounts of white and black paint used

Question 19

Collective behavior

Answer 19

Choosing to live in groups

Question 20

Pros of Collective behavior

Answer 20

Easy to find Mates
Reduced risk of predation: dilution effect, easier predator detection- many eyes to look for predator
Improved foraging success

Question 21

Cons of Collective Behavior

Answer 21

Faster food depletion
Greater competition for food
Conspicuousness may increase predation
Greater disease risk

Question 22

Optimal group size

Answer 22

Intermediate optimal value where maximized expected individual fitness
NOT STABLE!

Too small, low fitness
Too large, low fitness

Question 23

Stable group size

Answer 23

Point in which it is slightly better for an individual to join group than be on its own
Usually larger than optimal group size