Lecture 7: Animal Behavior

Discuss how genetics and environment interact in the development of the following behaviors: gulls pecking at parent’s bill for food; imprinting; and vocalizations in chickens, parrots, and swamp and song sparrows.

Gulls:
Genetic as they are born with the instinct. Environment as they improve with practice.
Imprinting:

Genetic as they are programmed to imprint. Environmental as they imprint on whatever moving object they see first.
Voccalization:
Chickens and sparrows are genetic, but the other have to learn and copy

Distinguish between classical and operant conditioning.

Classical: Associates an involuntary response and a stimulant

Bell —> food —> salivation

Operant: Associates a voluntary behavior and a consequence

Press lever —> get food

Be able to identify the US, CS, and UCR in a Pavlovian conditioning scenario.

US (Unconditioned Stimulus): Food

UCR (Unconditioned Response): Salivation

CS (Conditioned Stimulus): Bell paired with food

CR (Conditioned Response): Salivation to bell

Distinguish the response properties of the A1 and A2 auditory cells in moths.

A1 Cells: Respond to weak and moderate bat sounds, fire more when sound is more intense or close

A2 Cells: Respond only to very loud, close bat sounds, for imminent threats

Describe how the A1 and A2 cells help moths to (i) veer away from an approaching bat or (ii) initiate a power dive.

A1: Help the moth rotate/turn based on direction to escape early

A2: Triggers power dive

Explain how scout bees communicate distance and direction to a novel food resource (e.g., a patch of flowers) to hive mates.

Direction: The angle of the waggle = the angle of the food relative to the sun

Distance: Duration or number of waggles = how far the food is

Distinguish between the waggle dance performed outside versus inside the hive.

Outside: Angle of the dance = angle to sun in the outside world

Inside: Bees can’t see the sun. They use gravity instead. Straight up = toward the sun, angles = direction relative to the sun

Describe the life history of the Monarch butterfly, and explain why the fall population must migrate to Mexico or California each winter.

1. Egg

2. Caterpillar

3. Chrysalis

4. Adult

Winter in the U.S/Canada is too cold and there is no milkweed or nectar available

Justify the statement that Monarchs must rely on a genetically based navigation mechanism to locate the overwintering sites in Mexico.

The butterflies that migrate south are not the same ones that made the trip last year. They have no opportunity to learn the route from older butterflies.

Define sexual selection.

Natural selection related to obtaining mates. It favors traits that increase mating success, even if it doesn’t aid surivial.

Distinguish between mate choice and intrasexual competition.

Mate choice: One sex picks mates based on preferred traits

Females choosing males with bright feathers

Intrasexual competition: Members of the same sex compete directly

A male lion killing another male for access to the females

Explain why sexual selection is a “special case” of natural selection.

Sometimes sexual selection favors traits that don’t aid survival like bright feathers, but still get passed on because they increase mating