The function of orientation:Reading:Why does a swarm of honeybees founding a new nest sometimes choose a site more distant from the old colony rather than a closer site? What evidence supports this hypothesis?Reduces competition for food-identical hives created 50 and 200 metersWhat types of choices do aphids that establish their galls on a leaf after otheraphids have already been there face? What are the costs and benefits of settling near vs far from the midrib of the leaf?Fighting for territory at midrib-fewer nutrients away from midrib but do not have to fight for best habitatCompare the costs and benefits of natal dispersal for a Belding’s ground squirrel and a lion- which factors are similar? Different?Females both stay to care for young more easilyMale ground squirrels do not fight for mates like lionsWhat are some different explanations for territoriality in different species? Give specific examples.Monopolize resources and matesWhy do territory holders almost always win territorial battles? How were these ideas tested in speckled wood butterflies? What are alternative hypotheses that might apply to other species?More energy reserves-black won only when white butterfly was removedResource-holding powerLecture:What are natal dispersal and philopatry?Natal dispersal-permanent relocation away from birthplacePhilopatry-staying at birthplace as adultWhat are the pros and cons of staying in your birthplace versus leaving?Pros: avoid inbreedingCons: takes energy, mate competition, food competitionWhy is it often all the members of one sex that disperses? What determines which sex is the one that moves on?Avoid inbreeding and recessive diseasesFemale mammals provide care for young-stayMale mammals usually polygynous-leave to find matesMale birds-defend territories-stayIf you were hired by the USGS to determine whether the migrations of birds were getting smaller, how would you do it?Direct observation, record chirps, preserve specimens, banding, radio tracking and radar for large flocksGive examples of some of the costs of migration.Takes a lot of energy, more dangerous (predators and weather), and unfamiliar territoryWhat is a potential physiological adaptation by some birds that breed in the arctic to the very short breeding season?Breed during the short summer season when food sources are abundant for offspringIf migration is so costly, then why does it ever occur?Exploitation of natural resources, more favorable climate, avoid competition,encounter more suitable mates, and escape predatorsDampened stress receptors sense they must raise young in such short periodWhat are some reasons that a bird might migrate from the equator to the north pole to breed?Avoid competition for space and food at crowded equatorWhat can migrants do to mitigate the costs of traveling?Feed when depleted, fly at night and feed during day, find favorable wind and weather conditionsIn voles, what is the proof that the females defend territories to protect food resources?Females became more territorial when food became scarceWhat is the proof that male voles defend territories to protect access to females?Males became more territorial when females are less territorial-more food somore spread outWhat is evidence of the high costs of maintaining a territory?Males lose weight during breeding season (more patrolling and fighting)How was cost/benefit analysis (or optimality theory) applied to sunbird territories?Takes more energy to defend than being taken in when resources are abundant, but when resources are not, must defend for