Animal Behavior – information from Dr. Wright at NMSU; modified by Brian Fedigan

Behavior What is behavior? –How animals interact with environment and each other (in real time) Why is behavior interesting? –Lies at intersection of genetics, neurobiology, endocrinology, physiology, evolution, ecology –Evolves under natural and sexual selection –Animals do the strangest things

Ethology Two questions traditionally asked: 1) How animals behave (proximate causation). 2) Why they behave how they do (ultimate causation).

Influential Behavior Biologists Tinbergen wrote an influential book called “The Study of Instinct” Learned basic concepts of animal behavior by studying the egg-retrieval response of the greylag goose.

Tingergen’s study He presented a female greylag with an egg a short distance from her next. She would rise up extend her neck and pull the egg carefully in the neck. They noticed if they removed the egg once she began her retrieval or if it rolled away she would settle back on her nest unworried.

Stereotypical behavior The bird performed the egg rolling behavior as if it were a program. Once started it had to be finished. They viewed this as a “fixed behavior”, the pattern did not change. It began known as “Stereotypical behavior”.

Tinbergen’s four questions Causation: what is the underlying mechanism? Fitness: what is the survival value? Ontogeny: how does it develop? Evolution: how did it evolve?

Advertisement calls in the Tungara frog Males call in aggregations to attract females to oviposition sites Females select mate from among males based on call characteristics Movie from

Females chose males by calls Calls consist of ‘whines’ and ‘chucks’ Females ear tuned to frequency of chucks Females prefer males with deeper chucks Chuck frequency constrained by male body size

Sensory exploitation

Exploitation by Trachops bats Chucks make calling frogs more vulnerable to eavesdropping by predatory bats

Development of behavior, part 1 Most behaviors develop as interaction of genes and experience (nature and nuture) Innate behaviors develop with little effect of experience. –Fixed or modal action patterns –Releasers or sign stimuli

Innate Behavior Seems to be a preprogrammed behavior. They appear suddenly in animals and are preformed in animals of all ages. Orb weavers are born knowing how to make webs.

Releaser – A simple feature in the environment that would trigger certain innate behavior. Sign stimulus – An aspect of the releaser (sound, shape and color) that the animal responds to.

Innate releasing mechanisms Herring gull chicks use a moving red spot on bill as a sign stimulus to recognize their mother. A yellow stick with red spots acts as a super normal stimulus.

Chick begging and parasitism by cuckoos

Pup Offspring recognition: isolation calls in Mexican free-tailed bats

Isolation calls are heritable

Development of behavior, part 2 Learned behaviors result from experience Imprinting- The imposition of a stable behavior in a young animal by exposure to a particular stimuli during a critical period in the animals life. limited to a critical period early in life –Lorenz’s goslings that followed him after imprinting Social learning- learning from other individuals. Herd animals that remain and do things together by influencing one another. Trial and error learning- learning by an individual. Learn how to be successful by testing various hunting techniques for example.

Learned behaviors in parrots Nestlings naturally cross-fostered to Major Mitchell’s cockatoos Contact calls of foster species Begging and alarm calls of galahs Flocked and paired with foster species Mimicked their flight pattern Captive-bred birds released in Arizona Required extensive training in handling pine cones Poor flight and flocking skills Did not avoid natural avian predators Thick-billed parrots Photo: N. Synder Photo: G. Chapman Galahs

Vocal dialects in parrots North dialect South dialect 50 km mtDNA tree of individuals

Ontogeny and environmental change Innate –Easiest to encode, few mistakes when environment predictable Imprinting –Useful when little possibility of error in model but innate mechanisms is difficult to achieve Social –Can be rapid, benefit from past selection on models Individual –Best at tracking rapid changes within an individual’s lifetime Slow Rapid Rate of environmental change innate imprinting social learningindividual learning

Mating systems, part 1 Many different mating systems: they are classified into 2 main cateogories: –Monogamy: one male with one female –Polygamy: multiple partners of one sex Sexual selection is greatest on sex that competes for matings –Leads to elaborate behaviors and sexual dimorphism Females are often choosier sex, males compete for matings –Sperm are cheap relative to eggs

Sage grouse mating displays

Male contests in red deer

Behavior study Most studies of behavior are trial and error. Things are found out by mistake and continual observation. Observing captive animals presents a bias as to what really happens. Making yourself present in the animal kingdom may also be a distraction. Animals may not behave the same way because of your presence.

Animal Complexity Animals have different personalities and some are capable of amazing thought. Some of my bears would allow me to get very close to them, while others were extremely aggressive and would not tolerate my presence. It is hard to come up with one behavior that covers the species as a whole.