Behavioral Ecology: A Summary

AP BiologySpring 2011

Animals react to different stimuli which are genetic in nature ◦ Experiments performed by mating two types of

garter snakes with different food preferences helped to prove this

◦ Fruit flies show an identified genetic marker to indicate if they are “rovers” or “sitters”

Hormone production, which is genetic, influences animal behavior◦ Studies were performed on voles relating to

oxytocin levels and animal’s preference for monogamy

◦ Additional studies indicated a link between antidiuretic hormone and promiscuity in voles

Mutations can cause changes in behavior◦ Mutation in fruit flies results in an inability to

perform normal courtship activities ◦ In mice a mutation relating to oxytocin receptors

results in subnormal maternal behavior

Animals are born with some instinctive behavior◦ Ex. Procedure by which cuckoo birds discard other

eggs in foster parents nests

Some animal behaviors are learned ◦ Imprinting is when a particular behavior is

learned during a certain time period ◦ Ex. Baby geese following any maternal type figure

when exposed at an early age ◦ There appears to be a window of opportunity for

birds to learn a species-specific song

Animals can learn throughout life based on a positive and negative reward system

Classical conditioning: an animal connecting two stimuli together when presented at the same time ◦ Pavlov’s dogs salivating due to the anticipation of

food

Operant conditioning: occurs when an animal changes his behavior based on a positive-negative reward system

Habituation: when an animal learns a behavior even though it has not been exposed to a reward system◦ Lobsters lean to recognize another lobster that

they have battled

Observational learning: occurs when an animal learns to mimic an activity performed by another animal

Organisms can adopt behavior that benefits the individual’s reproduction◦ Study showed that birds include wild carrot into

their nest construction materials to deter mite infestation

Animals use various means of communication to relay information to another of their species◦ Pheromones are chemical signals and often active

in mate selection◦ Animals emit auditory signals to signal

prospective mates or to warn other of danger ◦ Tactile display involves one individual

transmitting a message by touching another Bees waggle dance relates the distance and location

of a food source to other bees http://www.youtube.com/watch?v=-7ijI-g4jHg

Individuals often compete in various ways for mating privileges known as sexual selection ◦ Male hangflies must bring large gifts of food to

win over females ◦ Females observe the male fiddler crabs waving

their large claw◦ Male birds put on a colourful display to impress

females ◦ http://www.youtube.com/watch?v=gKybAp--n7M

Many species involve parental care duties◦ Many birds and some mammals are cared for by

both parents◦ Young reptiles, with the exception of crocodiles,

do not require parental care

Often groups of animals deter predators ◦ Ex. Sawfish caterpillars and other animals such as

prairie dogs who give a warning call ◦ A selfish herd is when the members of a group of

animals tend to hide behind one another

Animals in groups may have advantageous feeding opportunities ◦ Group hunting may not actually provide more

food, but may be better for protection ◦ Animals in groups may learn behaviors from each

other like the utilization of tools in primates

Some animals establish hierarchies in their group structure ◦ Wolves develop packs and only the dominant

member can mate

In some circumstances, living in groups is disadvantageous◦ Groups may attract predators and spread

diseases more readily

Eusocial animals have developed a system where there are only a few breeding individuals◦ Insects that have this system: ants, termites,

bees◦ Other insects have auxiliary functions to support

the queen ◦ African mole-rats are the only mammals with this

organizational structure

Works in eusocial society show altruistic behavior, which means working towards the good of the group ◦ Theory of inclusive fitness explains that this

behavior helps to promote reproductive success of relatives

◦ Since relatives share the same gene pool, this behavior helps promote reproductive success of their own genes

Like many other animals, humans are affected by hormones and pheromones◦ It is felt that a lock of the hormone oxytocin may

result in a defective bonding pattern◦ Pheromones may be active in regulating the

menstrual cycles of women living in close proximity

Humans can perform infanticide under extreme conditions even though it is a practice considered to be amoral behavior