Animal Behavior

Behavior Behavior is what an animal does and how it does it Behavior is a result of GENETIC and ENVIRONMENTAL factors (nature vs nurture) The field of study that looks at how behavior is controlled and how it develops, evolves and contributes to survival and reproductive success 2 types Innate/Instinctive – preprogrammed, developmentally fixed Learned – developed throughout life

Ethology Ethology is the study of animal behavior A FIXED ACTION PATTERN is a sequence of innate behaviors that is largely unchangeable and usually carried to completion once it is initiated. Ex. Geese with eggs and male sticklebacks These are triggered by SIGN STIMULI

IMPRINTING A combination of learned and innate components that is limited to a sensitive period in an organism’s life and is generally irreversible

Directed Movement Kinesis – a simple change in activity in response to a stimulus (speed up or slow down) Taxis – an automatic movement toward or away from a stimulus Migration – cyclic movement over long distances

Kinesis increases the chance that a sow bug will encounter and stay in a moist environment. Dry open area Moist site under leaf

Positive rheotaxis keeps trout facing into the current, the direction from which most food comes. Direction of river current

Nature vs. Nurture? In biology, it’s not an either/or scenario Genes and the environment both influence behavior Exception - Innate behavior is behavior that is developmentally fixed, regardless of the environment

Animal Signals & Communication A signal is a behavior that causes a change in another animal’s behavior Communication involves the transmission of, reception of, and response to signals between animals Chemical Communication: Pheromones – particularly important in reproduction behavior, but other things as well Auditory Communication Visual Tactile

Learning Learning is the modification of behavior based on specific experiences Habituation: loss of responsiveness to stimuli that convey little or no information “crying wolf” Spatial Learning: the modification of behavior based on experience with the spatial structure of the environment, including the location of nest sites, hazards, food, and prospective mates

Nest No nest Nest

SPATIAL LEARNING COGNITIVE MAP – an internal representation of spatial relationships among objects in an animal’s surroundings ASSOCIATIVE LEARNING – ability of many animals to associate one feature of their environment with another feature

Associative Learning 2types Classical Conditioning an arbitrary stimulus is associated with a reward or punishment involves learning to associate certain stimuli with reward or punishment Pavlov’s Experiment Operant Conditioning “trial-and-error learning” occurs as a animal learns to associate one of its behaviors with reward or punishment Mouse eating distateful caterpillar

Cognition & Problem Solving Cognition is the ability of an animal’s nervous system to perceive, store, process, and use information gathered by sensory receptors Example: monkeys & bananas on string

Natural Selection & Behaviorism The genetic components of behavior evolve through natural selection Natural selection favors behaviors that increase survival and reproductive success Foraging behavior – Balance between benefits of nutrition and cost of finding food (predation, energy, etc.) Mate selection – selecting and competing for a mate Most animals are promiscuous Monogamous Polygamous

Environmental Influence on Behavior By interacting with an animal’s genetic makeup, the environment can influence the development of behaviors

AGONISTIC BEHAVIORS Ritualized contests that determine which competitor will gain access to a resource such as food or mates Social Interactions

Benefits of Social Groups Everything is a competition (cost vs benefit) Cooperative Predator Avoidance – social groups are formed to “protect” individuals Dominance Hierachies – social groups are formed for protection and mating, but there are definite dominant individuals. Subordinate individuals stay for protection, food and a maybe a chance to mate. Selfish Herd – social groups held together for reproductive self interests but some individuals are protected just because of their position in the group.

Altruism & Inclusive Fitness Most social behaviors are selfish Altruism = when an animal behaves in a way that reduces its individual fitness but increases the fitness of the other individuals in the population Example: worker bees Helps close relatives (children, siblings, etc.), thereby increasing the individual’s genetic representation in the next generation – “inclusive fitness” or kin selection

*Courtship – “Dating” relationships/behaviors. Courtship in the animal kingdom is the process in which the different species select their partners for reproduction purposes. -May include dances, “beauty” displays, vocalizations, fighting/dominance displays, etc. -Sexual Selection – competition for mates