Responses to the environment AP Biology

Learned behavior

behavior that an animal is not born with, but one that develops through experience. Animals can be trained using positive and negative reinforcement to avoid or reinforce behaviors.

Innate Behavior

This behavior is something an animal is born with, they are sometimes referred to as instincts or intrinsic behavior. Biologists make an assumption that the code for innate behaviors must be found within the DNA of the organism and passed from one generation to the next

Types of learning

associative learning, habituation, imprinting

Associative learning

the ability to associate one environmental feature (like color) with another (like foul taste)

Habituation

a loss of responsiveness to stimuli that convey little or no new information; allows an animals nervous system to avoid wasting energy on stimuli that are irrelevant to the animals survivial and reproduction

Imprinting

includes both learned and innate components; the formation of a long-lasting behavioral response to a particular individual or object (formed at a specific stage of life); the critical period is the limited developmental phase when these certain behaviors can be formed

Ethology

the study of animal behavior and is most often concerned with innate behaviors.

Two points of view that biologists study animal behavior from

proximate questions and ultimate questions

proximate questions

address the mechanisms that produce a behavior. the environmental stimuli that trigger a behavior and physiological mechanisms that make it possible. Ex: how does a animal carry out a behavior?

Ultimate questions

address the evolutionary significance of a behavior. how a behavior increases the evolutionary fitness of the animal demonstrating it, helping it to survive and reproduce in its environment. Ex: why does the animal show this behavior?

Fixed action pattern

a sequence of unlearned acts that is essentially unchangeable and, once initiated, is usually carried out to completion

External que for fixed action pattern

sign stimulus

Example of fixed action pattern

Male sticklebacks wil lattack any other males that invade their nesting territories due to the red color of their underside. The fish also act aggresively when a red truck passes, showing the red coloration is a sign stimulus for the fixed action pattern.

homeostatic mechanisms

Mechanisms that keep a stable internal environment of organisms

Feedback mechanisms

used by organisms to regulate growth and reproduction and to maintain dynamic homeostasis. Respond to changes in their internal and external environments through behavior and physiological mechanisms like sweating, migration, shivering.

Negative feedback

Organisms use this to maintain the internal environment by returning the changing condition back to its set point. Ex: temperature regulation in animals, responses to drought in plants

Negative taxis

animals avoid stimulus

Positive taxis

animal moves toward stimulus

Kinesis

random movement of an animal in relation to a stimulus, like cockroaches scattering when the light is turned on

Photoperiodism

the physiological reaction of organisms to the length of night or a dark period