Discrete sensory inputs can stimulate both simple and complex behaviorsCHAPTER 51, SECTION 1 8/28/2015

Overview

The Dutch scientist Niko Tinbergen suggested that understanding any behavior requires answering four questions:

1. What stimulus elicits the behavior, and what physiological mechanisms mediate the response?

2. How does the animal’s experience during growth and development influence the response?

3. How doe the behavior aid survival and reproduction?

4. What is the behavior’s evolutionary history?

Behavioral ecology: the study of the ecological and evolutionary basis for animal behavior.

Fixed Action Patterns

Definition: a sequence of unlearned acts directly linked to a simple stimulus. The trigger for the behavior is an

external cue called a sign stimulus.

Example: Three-spined sticklebacks

Example: Greylag Goose

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

Migration

Definition: a regular, long-distance change in location.

In the course of migration, many animals pass through environments they have not previously encountered. How do they find their way? Solar or celestial cues

Earth’s magnetic field

Behavioral Rhythms

Circadian RhythmDefinition: a physiological cycle of about 24 hours that persists even in the absence of external cues.

Example: release of hormones

Circannual RhythmDefinition: behavioral rhythms linked to the yearly cycle of the seasons.

Examples: migration, hibernation

CircalunarDefinitions: behavioral rhythm linked to the cycles of the moon rather than the amount of light.

Example: reproductive system of marine organisms

Forms of Animal Communication

A stimulus transmitted from one animal to another is called a signal.

Signal transmission and reception constitute animal communication, an essential element of interaction between individuals.

Four common modes of animal communication: visual, chemical, tactile, and auditory.

Example: Male fruit flies exhibit all four types of communication when attempting to attract a female.

https://www.youtube.com/watch?v=B-iK2D1mC10

https://www.youtube.com/watch?v=1lhVBNQ-Ik8

Pheromones

Definition: a small molecules released into the environment that functions in communication between members of the same species.

Pheromones are not limited to short distance signaling silkworm moths

Pheromones may serve as an alarm signal. 2 hypotheses

Fathead minnow

Honeybees produce pheromones to maintain order.

https://www.youtube.com/watch?v=IC4yuC0Ld8k