Ch51 Behavior Ecology

• Behavioral ecology is the study of the ecological and evolutionary basis for animal behavior

• A fixed action pattern a sequence of unlearned, innate behaviors that is unchangeable

• Once initiated, it is usually carried to completion

• triggered by an external cue, a sign stimulus

https://www.youtube.com/watch?v=ZfcGZCGdGVE&list=PL4C2DAEF2C65122DE

http://www.youtube.com/watch?v=vUNZv-ByPkU

• Fixed Action Pattern in Geese:– If an egg is taken from them they will not stop

until it is returned, ‘head bobbing motion’ to roll egg back to nest.

What role does the environment play in signaling?

• Phototropism – growth of a plant towards (+) or away (-) from light

http://plantsinmotion.bio.indiana.edu/plantmotion/movements/tropism/phototropism/corn/cornworship.html

Sunflowers track the sun Why?

Circadian Rhythms

• Process that follows a routine 24 hour cycle

• What is the signal?

https://www.youtube.com/watch?v=mUwbbLZANVE

Photoperiodism• A physiological response to the relative

lengths of day and night

Brain makes melatonin

• When there is less light, the SCN tells the brain to make more melatonin so you get drowsy.

Melatonin controls sleep

Jet lag

• What is the signal?

Monarch Migration

• The navigation of the fall migration of the Monarchs to their overwintering grounds in central Mexico uses a "sun compass" that depends upon a circadian clock in their antennae.

https://www.youtube.com/watch?v=x0m_rK_WpjQ

Animal Signals and Communication

• signal is a behavior that causes a change in another animal’s behavior

• Communication is the transmission and reception of signals

Fruit fly courtship

• http://www.hhmi.org/biointeractive/fruit-fly-courtship

Figure 39.16

(a) Worker bees (b) Round dance (food near)

(c) Waggle dance (food distant)

Location A Location B Location C

Beehive

A

BC

30

30

Waggle Dance• A bee returning from

the field performs a dance to communicate information about the distance and direction of a food source

http://video.nationalgeographic.com/video/weirdest-bees-dance

Nature vs. Nuture

• what behaviors are genetically based and what is learned (Nature vs. Nurture)

Serial Killer, Ted Bundy

Is a serial killer born that way?

Cross-fostering Exp• CA mice: aggressive, lots parental care• White-footed mice: less aggressive, little parental

care

Table 39.2

What can you conclude? Nature vs Nuture?

Dogs Decoded: At 31 Minutes: http://www.youtube.com/watch?v=yN96Gid6Kjo

Prey Selection

• Coastal populations feed mostly on banana slugs, while inland populations rarely eat banana slugs

• Studies have shown >60% Coastal snakes ate the banana slugs, <20% of inland snakes did

Figure 39.25

What can you conclude? Nature vs Nuture?

Cross-fostering Exp

Genetics or Environment?

• Twin Studies-Compare identical twins raised apart vs twins raised together

Learning

• the modification of behavior based on specific experiences

• Imprinting – the establishment of a

long-lasting behavioral response to a particular individual during a specific time in development, the sensitive period

Figure 39.17a

(a) Konrad Lorenz and geese

Conservation efforts

• Young whooping cranes can imprint on humans in “crane suits” who then lead crane migrations using ultralight aircraft

Figure 39.17b

(b) Pilot and cranes

Spatial learning

• digger wasps use landmarks to find nest entrances

Figure 39.18 Experiment

Pinecone

Results

Nest

NestNo nest

http://www.flyfishingdevon.co.uk/salmon/year1/psy128ethology_experiments/wasp_learning_activity.htm

Associative LearningFigure 39.19

Blue Jay learns that Monarchs will cause them to vomit

Classical Conditioning (Pavlov's Dogs) 

OPERANT CONDITIONINGInvolves "training" a behavior using a reward or punishment system.  

Skinner Box

Mating Systems and Parental Care

• Monogamous vs Polygamous?

• Is paternal care crucial for survival of offspring?

• Certainty of paternity?

Altruism

• Natural selection favors behavior that maximizes an individual’s survival and reproduction – selfish

• some animals behave in ways that reduce their individual fitness but increase the fitness of others - altruism

Inclusive fitness & Kin selection• natural selection that

favors this kind of altruistic behavior by enhancing reproductive success of relatives

• Ex:• Belding ground squirrels

– alarm call when predators nearby

• Naked mole rats – in colonies of 75+, only one queen and 3 kings do all the reproduction

Hamilton’s rule

• Natural selection favors altruism when rB C

• This inequality is called Hamilton’s rule• Would you risk your life to save your

brother/sister?

Yes!• Assume the average individual has

two children. As a result of the sister’s action

– The brother can now father two children, so B 2

– The sister has a 25% chance of dying and not being able to have two children, so C 0.25 2 0.5

– The brother and sister share half their genes on average, so r 0.5

• If the sister saves her brother, rB ( 1) C ( 0.5)

Figure 39.27

Parent A Parent B

Sibling 1 Sibling 2

½ (0.5)probability

OR

½ (0.5)probability