AP Biology Ethology is the study of animal

AP Biology

� Ethology is the study of animal behavior

Behavioral ecology— studies the interactions of animals and their environments Seeks to explain how specific behaviors increase individual reproductive success Behavior that is influenced by genes is molded by natural selection and other evolutionary forces. As a result, most genetically based behaviors should increase the fitness of the individual.

� Associative learning is the process by which animals take one stimulus and associate it with another.

Pavlov taught dogs to anticipate the arrival of food with the sound of a bell. He hooked up these poor dogs to machines that measured salivation. He began the experiments by ringing a bell just moments before giving food to the dogs. Soon after, the dogs were salivating at the sound of the bell before food was even brought into the room. They were conditioned to associate the noise of the bell with the impending arrival of food.

A fixed-action pattern is an innate, preprogrammed response to a stimulus. Once this action has begun, it will not stop until it has run its course. This is one of the few types of animal behaviors that can truly be said to be “hard-wired”. Mating dances of birds http: //www. youtube. com /watch? v=l. Mb. Dj. NDD 4 c. M http: //www. youtube. com /watch? v=Xgn. OQq. Lhrlw When a graylag goose sees an egg outside her nest, she will methodically roll the egg back to the nest using her beak. An egg outside her nest is the stimulus. She will also retrieve any object that looks like an egg and once the FAP has begun, she will continue the retrieval motions until she has completed all the way back to her nest.

� In Spring male sticklebacks change color, establish a territory and build a nest. They attack male sticklebacks that enter their territory, but court females and entice them to enter the nest to lay eggs. In a famous experiment by Tinbergen, he showed that the stimulus that invoked the response was the color of the fishes’ bellies.

Habituation is the loss of responsiveness to unimportant stimuli. This is learned behavior that allows the animal to disregard meaningless stimuli. Prairie dogs give alarm calls when mammals, large birds, or snakes approach. When prairie dog towns are located near trails used by humans, giving alarm calls every time a person walks by is a waste of time and energy for the group. Habituation to humans is an important adaptation in this context.

� Jane Goodall's famous studies of chimpanzees depended on the chimpanzees learning to tolerate her presence. At first, Jane Goodall could only study chimpanzees from far away, but she gradually won the trust of the Gombe chimps, enabling her to study their behavior up close.

� Imprinting is an innate behavior that is learned during a critical period early in life. Once acquired, the behavior is irreversible. Salmon hatch in freshwater streams and migrate to the ocean to feed. When reproductively mature, they return to their birthplace to breed, identifying the exact location of the stream. During early life, they imprinted the odors associated their birthplace.

� In a classic example of imprinting, ethologist Konrad Lorenz discovered that, during the first day of life, graylag goslings will accept any moving object as their mother. When Lorenz himself was the moving object, he was accepted as their mother for life. Any object presented after the critical period, including their real mother, was rejected.

Insight learning is the ability to do something right the first time with no prior experience. It requires reasoning ability—the skill to look at a problem and come up with an appropriate solution. http: //www. youtube. com/watch? v=f. Pz 6 uv. I b. WZE

Observational learning is the ability of an organism to learn how to do something by watching another individual do it first, even if they have never attempted it themselves.

This is a type of associative learning that is based on trial and error. This is different from classical conditioning because the association is made between the animals’ own behavior and a response. The animal connects its own behavior with a particular environmental response. B. F. Skinner trained rats to push levers to obtain food or to avoid painful shocks. Learning acquired by operant conditioning can be forgotten or reversed if the performed behavior no longer elicits the expected response.

A brightly colored animal with a chemical defense mechanism (relies on operant condition for its survival. The coloration pattern is there in the hope that the predator will, in a trial-anderror fashion, associate the coloration pattern with the uncomfortable chemical experience it had in the past. This association might make the predator think twice before attacking in the future and provide the prey with enough time to escape.

Kinesis—a seemingly random change in the speed of a movement in response to a stimulus. When an animal is in a place it enjoys, it slows down and when in a bad environment, it speeds up. Overall, this leads to the animal spending more time in favorable environments. Lifting a log in the forest will reveal many insects scurrying around to get out the light. These movements are kinesis.

Taxis is a directed Moths are attracted to light; movement in sharks move response to a towards food when food odors stimulus. reach them by Movement is diffusion in ocean currents. directed either toward or away from the stimulus. Movement towards light is called phototaxis.

Migration is the long -distance, seasonal movement of animals. It is usually in response to seasonal availability of food or degradation of A map depicts the migration of 19 sooty environmental conditions (they shearwaters that were tracked using electronic tags in a recent study. The research showed that usually occur the birds (pictured inset) migrated 40, 000 miles together) a year, flying from New Zealand to the North Pacific and back. It is the longest animal migration ever recorded electronically.

Communication in animals is commonly used in species recognition, in mating behavior, and in organizing social behavior.

Chemicals used for communication are called pheromones. Chemicals that cause immediate and specific behavioral changes are releaser pheromones (they “release” the behavior) Those that cause physiological changes are called primer pheromones. Female moths emit releaser pheromones to attract male moths. Ants secrete a releaser pheromone to mark trails that guide other ants to food.

� Queen bees, queen termites, and queen ants secrete primer pheromones that are eaten by workers. The pheromone prevents development of reproductive ability. � Many male mammals spray urine throughout their territories(especially along their borders) to warn other animals of the same species to keep out.

� Many visual displays are observed in animals during displays of aggression (agonistic behavior) or during courtship. Wolves make threatening gestures by staring and baring their teeth. Lowering their tails and lying on their backs are submissive behaviors. Two male Sage Grouse are displaying for each other to warn the other and make a courship display for the females

� Sounds are commonly used to communicate over long distances, through water, and at night. http: //www. youtube. com/watch? v=fytk. U Hwrga. E&feature=fvwrel � http: //www. youtube. com/watch? v=937 A 1 EL Vy. Us

� This mode of communication involves touch in the conveying of a message and is often used as a greeting. A major form of primate tactile communication is grooming.

� Bees provide an example of communication that involves chemical, tactile, and auditory components. � When a bee returns from foraging, to tell the other bees about his “find”, he dances in a tight circle accompanied by a certain wag that will tell the co-workers where the food is. If the food is farther away, the dance changes to show direction and distance. � In addition, to “sweeten” the find, he will regurgitate a bit of the food to show the other bees what kind of food they will be finding. � http: //www. youtube. com/watch? v=b. FDGPg. Xt. KU&feature=related

� Agonistic behaviors result from conflicts over resources. It often involve intimidation and submission. The battle is often a matter of who can put on the most threatening display to scare the other one into giving up. � Agonistic behaviors can involve food, mates, and territory. Participants do not tend to come away injured because most of these interactions are just displays. http: //dsc. discovery. com/videos/life -videos/

� An altruistic action is one in which an organism does something to help another, even if it comes at its own expense. � Examples: worker bees are sterile, produce no offspring and play the role of hive defenders sacrificing their lives by stinging intruders that pose a threat to the queen bee. Vampire bats vomit food for group mates that did not manage to find food

�A dominance hierarchy among a group of individuals is a ranking of power among the members. The member with the most power is the “alpha” member. The second-in-command is the “beta” member—they dominate everyone in the group except the alpha. Alpha members have first dibs on everything—mates, food, etc. Note: Since there is an order, known by all involved, it reduces the energy wasted and the risk from physical fighting for resources. Dominance hierarchies are characteristic of group-living animals.

� Foraging describes the feeding behavior of an individual. This behavior is not as random as it seems as animals tend to have something called a search image that directs them toward their potential meal. When searching for food, few fish look for a particular food; rather, they are looking for objects of a particular size that seem to match the size of what they usually eat. This is a search image.

� Natural selection favors animals that choose foraging strategies that take into account costs and benefits. Food that is rich in nutrients but far away may cost too much energy to be worth the extra trip. There are many potential costs to traveling a long distance for food.

� Territorial individuals defend a physical geographic area against other individuals. This area is defended because of the benefits derived from it, which may include available mates, food resources, and high-quality breeding sites. � An individual may defend a territory using scent markers, vocalizations that warn other individuals to stay away, or actual physical force against intruders. Spider monkeys scream, bark, rattle branches, and even throw branches and feces to defend their territory.