animal behavior
Overview
Animal Behavior: Behavior is a nervous system’s response to a stimulus carried out by either the muscular or hormonal system.
Importance of Behavior: Essential for animals to:
Obtain food
Find partners for sexual reproduction
Maintain homeostasis
Ethology
Ethology: The scientific study of animal behavior, particularly in natural environments.
Niko Tinbergen’s Four Questions About Behavior:
What stimulus elicits the behavior, and what physiological mechanisms mediate the response?
How does the animal’s experience during growth and development influence the response mechanisms?
How does the behavior aid survival and reproduction? (Survival value)
What is the behavior’s evolutionary history?
Proximate vs. Ultimate Questions: Highlights the different perspectives on behavior – proximate mechanisms relate to immediate causes, while ultimate questions consider evolutionary significance.
Behavioral Ecology: The field studying the ecological and evolutionary basis for animal behavior.
Fixed Action Patterns (FAP)
Fixed Action Patterns: Sequences of unlearned, innate behaviors that are unchangeable.
Completion: Once initiated, they are carried to completion.
Sign Stimulus: An external cue that triggers a FAP.
Example: Male stickleback fish attack behavior is triggered by the red underside of an intruder.
Movement Responses
Taxis
Taxis: An automatic, oriented movement toward or away from a stimulus.
Example: Stream fish exhibit a positive taxis by swimming upstream to avoid being swept away and to face the direction from which food will come.
Kinesis
Kinesis: A non-directional change in activity or turning rate in response to a stimulus.
Example: Sow bugs become more active in dry areas and less active in humid areas, without moving toward or away from specific moisture levels.
Migration
Migration: A regular, long-distance movement.
Orientation Strategies:
The position of the sun along with an internal circadian clock.
The position of the North Star.
The Earth’s magnetic field.
Behavioral Rhythms
Circadian Rhythm: A daily cycle of rest and activity.
Circannual Rhythm: Behaviors linked to changing seasons, such as migration and reproduction.
Lunar Cycles: Some animal behaviors, like courtship in fiddler crabs, are linked to lunar phases (new and full moon).
Animal Signals and Communication
Signals: Behaviors that alter another animal’s behavior.
Communication: The process of transmitting and receiving signals.
Types of Signals: Animals communicate using visual, chemical, tactile, and auditory signals, closely related to their lifestyle and environment.
Example: Honeybees perform dances to communicate the direction and distance of food sources, notably using the waggle dance.
Pheromones
Pheromones: Chemical substances that convey messages through odors, effective at low concentrations.
Example: Alarm substances in injured fish that induce fright responses in other fish nearby.
Learning and Behavior Modification
Innate Behavior: Fixed and genetically influenced behaviors that an organism is born with.
Learning: The modification of behavior based on experience.
Habituation
Habituation: A simple learning form where an organism stops responding to unimportant stimuli.
Example: Birds ignoring alarm calls that are not followed by an attack.
Imprinting
Imprinting: A behavior involving a critical learning period that is generally irreversible and consists of learned and innate components.
Sensitive Period: The specific developmental timeframe when particular behaviors can be learned.
Example: Young geese following the first moving object they see, such as their mother or a human.
Spatial Learning
Spatial Learning: A complex modification of behavior based on the spatial structure of the environment.
Cognitive Map: An internal representation of spatial relationships within an animal’s environment.
Example: Digger wasps using landmarks to find their nests.
Associative Learning
Associative Learning: Animals connect one aspect of their environment with another.
Examples:
Mice avoid certain caterpillar colors after negative experiences with bad-tasting ones.
Classical Conditioning: A learning process where a stimulus begins to elicit a response due to its association with another stimulus.
Example: Dogs salivating at a bell after it is repeatedly paired with feeding.
Operant Conditioning: Associating behavior with rewards or punishments, often used in training pets.
Example: A rat learns to push a lever to receive food.
It is also referred to as trial-and-error learning.
Problem Solving
Problem Solving: Devising strategies to overcome obstacles.
Example: Chimpanzees stack boxes to reach suspended food.
Some animals learn problem-solving by observing others, such as young chimpanzees learning to crack palm nuts by imitating older chimpanzees.
Mating Behavior and Mate Choice
Mating Behavior: Involves the processes of seeking, attracting, choosing, and competing for mates.
It is influenced by sexual selection, a specific type of natural selection.
Types of Mating Systems:
Promiscuous: Mating with no strong pair bonds.
Monogamous: One male mates with one female; often shows similar external morphologies between sexes.
Polygamous: One individual of one sex mates with multiple individuals of the other sex; usually, species are sexually dimorphic.
Polygyny: One male mates with several females; males tend to be larger and more showy.
Polyandry: One female mates with multiple males; generally rare and the females are often showier than males.
Influence of Young’s Needs on Mating Systems:
Monogamy may evolve when continuous care of offspring is necessary.
In contrast, polygyny might arise when offspring can soon care for themselves.
Paternal Certainty and Parental Care
Paternal Certainty: Influences mating behavior and parental care; generally higher in species with external fertilization.
Often, paternal investment is lower in species with internal fertilization due to the separation of mating and birthing.
In species with external fertilization, males are often likely to provide care as females are.
Mate Choice and Competition
Female Choice: A form of intersexual competition where females select mates based on specific traits.
Example: Female stalk-eyed flies prefer males with longer eyestalks, which may indicate vitality.
Male Competition: Intrasexual selection sourced from males competing for mates, which may result in behavioral contests called agonistic behavior.
Altruism and Inclusive Fitness
Altruism: Behavior that reduces individual fitness but enhances the fitness of others.
Example: Belding’s ground squirrels may alarm call to warn others of a predator, risking their safety.
Inclusive Fitness: The overall effect of an individual's actions on its own gene propagation, including its offspring and assistance to relatives.
Evolution and Human Culture
Sociobiology: Understanding human behavior through evolutionary interactions between genes and environment, acknowledging that culture may distinguish humans from other species.
Questions for Review
State Tinbergen’s four questions while identifying their proximate or ultimate causation.
Differentiate between kinesis and taxis, circadian and circannual rhythms, and classical vs. operant conditioning.
Suggest proximate and ultimate causes for imprinting in geese.
Explain how associative learning aids predators in avoiding toxic prey.
Describe the significance of cross-fostering experiments in genetic versus environmental behaviors.
Explain optimal foraging theory.
Define and identify differences among promiscuous, monogamous, and polygamous mating systems.
Distinguish intersexual and intrasexual selection.
How can game theory inform alternative behavioral strategies?
Define altruistic behavior and its types.
Contrast kin selection with reciprocal altruism.
Define social learning and culture.