AP Biology
Behavioral Ecology
Part 1
Important concepts from previous
units:
• DNA is responsible for being the “blueprint
information” for making proteins and
enzymes.
• Enzymes and proteins are the workhorses
within cells.
• Energy is necessary to carry out all cellular
processes except osmosis or diffusion (passive
transport).
• I. Organismal Behavior (What an organism
does and how it does it basically.)
•
A. Behaviors evolve over time based on
awareness and survival benefit.
•
B. Organisms are 50% genetics and 50%
experiences. (This is the nature vs. nurture
argument.)
•
C. Behavior can be influenced by an
organism’s interactions with other organisms.
•
D. Outward behaviors (are observable) vs.
inward behaviors (are the results of learning
mainly).
• II. Innate Behavior – These are behaviors that
an organism is born with. (Behavior is coded in
the genes- DNA.)
•
A. It is said to be developmentally fixed.
This is because development is governed by
the genes inherited.
•
B. The behavior is the same among all
members of the same species. (Babies crying
when hungry or Dogs barking.)
Babies Crying
Barking
Does this
experiment
suggest that nest
building is an
innate behavior or
a learned
behavior?
Is there a genetic basis for food preference?
Background: In California, there
are two populations of garter
snakes.
Coastal snakes eat slugs
Inland snakes eat aquatic
organisms such as fish and frogs.
Inland snakes refuse to eat slugs in a lab, hybrids of will have an
intermediate acceptance of slugs.
Further experiments showed that inland snakes are not sensitive to
a slug’s smell.
Does this support an innate or a learned cause for the behavior?
How can you determine whether a behavior is
something that is innate or something that has been
learned?
In humans, twin studies showed that even in twins that
were raised separately, there were startling similarities.
Some human instincts….
Serial Killer, Ted Bundy
Is a serial killer born that way?
III. Ethology (A.K.A. Behavioral Science)
The science concerned with how an organism behaves
in its natural environment.
B. Fixed Action Pattern (FAP’s for short)
1. This is a behavior, that once it is initiated, it
must be carried through to some fixed conclusion.
2. It is initiated by a trigger “sign” stimulus.
For example: Cardinal attacking red crate paper
near it’s nest. (trickery)
Moth hit by bat radar plays dead to avoid
capture.
Baby hand grasping an object put in it’s palm.
Cardinals
Baby Hand Grasping
Fixed Action Pattern
3. Survival? (Organisms that survive get to
reproduce and pass on those DNA traits to the
gene pool.)
Jane Goodall & Ethology
https://www.youtube.com/watch?
v=-Rht64izLQg
• Diane Fossey studied gorillas in the natural
habitat.
• Used mirroring technique-copied the gorillas’
behavior to get close to them
IV. Behavioral Ecology
A. The study of behavior as it relates to evolving
within an environment.
1. Natural selection plays a huge role in these
behaviors evolving.
a. Different rates of reproductive success due to
behavior. (Good behavior vs. Harmful Behavior)
b. Strong traits survive and reproduce more to
make more offspring with those good traits.
c. Weak individuals die off weeding out the
genes that were “weak” or not beneficial.
B. Foraging (Organisms Finding food)
1. Optimal foraging theory (This is
basically a cost analysis of energy input vs.
energy yield.)
2. Crow and Whelk experiment:
Basically Crows that learn to drop the whelk
from 5 m get the most energy out of their
food vs. energy input (Flight). Those that go
below 5m will have to expend more energy by
more flights to crack the welk. Those that fly
higher are also wasting more energy than
need be.
Foraging Theory
125
60
Average number of drops
50
100
40
Average number of drops
30
75
Total flight height
20
Drop height
preferred
by crows = 5.23 m
10
50
25
0
2
3
5
7
Height of drop (m)
15
3. Reproductive fitness and Energy? (Those
organisms that save energy on foraging will
mostly use that saved energy in reproducing.
So most fit genes get passed on the most.)
a. “Positive” learning is rewarded and
promoted by natural selection.
• Slides 8-12 taken from animal behavior
powerpoint on biologycorner.com