BZ 300 1st Edition Lecture 21Outline of Last Lecture I. Parental Investment Continued…a. Factors that Favor Parental Careb. Who invests and Why?i. Uniparental Caregivingc. Male Parental Care is not uncommon, why?i. Internal Fertilizationii. External Fertilizationd. Biparental Caregivinge. Hormones and Parental Carei. Prolactinii. Oxytociniii. Testosteronef. Parenting and Conflicts of Interesti. When should parental behavior cease?ii. Treatments of siblings similar to parenting COIiii. Begging and Weaningiv. Sibling Conflictv. InfanticideII. Aggression and Territoriality a. Aggressioni. Agonismii. Types of Aggressioniii. Ritualizationb. Territorialityi. Home RangeOutline of Current LectureI. Territoriality cont…a. Defenseb. Ideal Free DistributionII. Social Behavior, Cooperation, Kinshipa. Societyb. Benefits of Living in Groupsi. Protectionii. Foodiii. Informationiv. Division of Laborv. Offspring Carevi. Thermal Advantagesvii. Locomotory Advantagesc. Disadvantagesi. Competitionii. Diseaseiii. Interferenceiv. Predationv. Increase in Inbreedingvi. Misdirected Parental Cared. Altruism/Self Interesti. Fisher (1930)ii. Darwin (1859)iii. Wynne-Edwards (1962)iv. Definitions1. Altruism2. Donor 3. Recipientv. Group Sizevi. Dominance HierarchiesCurrent LectureI. Territoriality cont… a. Defense- territoriality around a home range, both random and non randomb. Ideal free distribution- random distribution, environmental factors do notaffect their area, they are not territorialc. Aggression in general is not evident for territorialityNew Section! Will NOT be on Exam ThreeII. Social Behavior, Cooperation, Kinshipa. Society: A group of individuals, same species, organized cooperatively, beyond sexual and parental behavior. Because there is cooperation going, we have to ask why we have deviation from baseline of evolution as why it is all about fitness and competition? Cooperation has a few more subtleness. b. Benefits of living in groupsi. Protection-1. One type of protection is alarm vocalization among members of society. Must be hard to locate, understood by recipient, short/high pitched sounds enough to travel and not locate. Predator specific alarms. a. The bigger the flock (up to a certain point) respond to predators quicker because there were essentially more eyes to see the threat and less time was neededto be vigilant. 2. Social groups are much better to repel predators3. Dilution effect: A group of animals can swarm one predator, and decrease the risk of one member getting hurtand less vigilance needed. Being part of the herd is efficientenough. Generally true with terrestrial predators. 4. Selfish herd: Different from dilution effect, still in a group,but in a location (usually middle) that is the safest. Different locations that benefit animals more or less. 5. Mobbing: A bunch of little birds chasing after one large bird that may be attacking nest or eggs. 6. Protection form members of same species: Matrolinear groups may be cohesive to protect offspring form other members of the group, who may be wanting to harm the offspring. ii. Food1. Cooperative Hunting2. Information Sharing on where food is, other animals in group benefit from seeing that information. When one animal returns with a successful prey, the other animal usesthat information to learn which direction the prey is.iii. Information1. Public Information- eavesdropping, can get information that is not intended for you. Can be extremely helpful.iv. Division of Laborv. Offspring Care- assistance in rearing offspring.1. Helpers can increase the number of survived offsprings2. Young can benefit from being in a large rich, highly stable groupvi. Thermal Advantages- insects as a group can build nests that are highly thermoregulatory.vii. Locomotory Advantagesviii. Reproductive Stimulation- for may animals getting into a reproductive states may require social interactions among conspecifics. c. Disadvantagesi. Competition, Aggression: Can be costly, result in high starvation rates. Competition is highii. Disease- really high numbers of social groups can pass parasites much quicker when directly transmitted. 1. Emerging diseases keep appearing because our contact level is increasing and our interaction and travel is widespread. iii. Interferenceiv. Predationv. Increase in Inbreedingvi. Misdirected Parental Cared. Altruism/ Selfish Interest: Should it exist? Shouldn’t animals only be worried about their offspring and their own fitness?i. Fisher 1930. The genetically Theory of Natural Selection1. Put the emphasis of natural selection acting on the individual, first of his time to do so.ii. Darwin (1859): Darwin believed that pure altruism cannot happen with his hypothesis, and is not natural. “If it could be proved that any part of the structure of any one species had been formed for exclusive good of another species, it would annihilate my theory” iii. Wynne-Edwards (1962)- Animal Dispersion in Relation to social behavior. If genetic based, it is unlikely to give up your fitness value for the benefit of othersiv. Definitions:1. Altruism- behavior performed without regard for self-interest2. Donor- animal that gives aid. The cost becomes the benefit to the recipient3. Recipient-Receives aid and benefits4. For natural selection to favor altruism, the benefit has to succeed the cost or it would not persist. In genetic terms thebenefit would be an increase in the genetic terms, and the cost would be the decrease in genetic terms. a. For natural Selection to favor aid giving: B>C. Benefit of donor is greater than cost of donor.b. Basis of Hamilton’s Rule: b/c>1/rc. Inclusive fitness: An organisms fitness is not just itsown fitness, but an organisms ability to pass on its fitness to other offspring but taking in account the fitness of relatives as well.v. Group Size1. Is there an upper limit on dilution effect and group size?2. Different species in different environments will vary in the group size and the benefits.3. Food Competition4. Predator Attraction5. Plateau Value of Vigilancevi. Dominance Hierarchies- animals are either physical or chemical dominant towards the rest of the group. 1. Linear Hierarchies are the best know2. Despotic3. Coalition based hierarchies4. *Note: Look In book for explanations!5. Why stay in a group if there are dominant hierarchies, and you are at the bottom?a. Even if you are at the bottom the barrel, it may be better to be with the group than try to survive on your own.b. Dominant