Intro. to Behavioral Ecology

Intro. to Behavioral Ecology Behavioral Ecology 1. Define behavioral ecology a. The study of how organisms respond to particular biotic and abiotic stimuli in their environment 2. Types of Behavior a. Movement & Migration (innate) b. Living in Groups (innate) c. Simple Learned Behavior d. Conditioned Behavior e. Cognitive Learning 3. Describing behavior a. Innate vs. Learned b. Fixed vs. Flexible 4. Understanding behavior a. Proximate vs. Ultimate i. Proximate (mechanistic/how) 1. What causes the behavior? 2. What does the organism do in response? ii. Ultimate (evolutionary/why) 1. What about the behavior helps the animal survive/reproduce? 2. What is the evolutionary history of the behavior?

Innate: Movement & Migration 1. List types of movement/migration from least to most complex a. Reflex b. Taxis c. Fixed Action Patterns i. Behavior : a male stickleback fish attacks other male sticklebacks that invade its nesting territory 1. Prox. Cause: a. Example - The red belly of the intruding male acts as a sign stimulus that releases aggression in a male stickleback 2. Ulti. Cause: a. Example - By chasing away other male sticklebacks, a male decreases the chance that eggs laid in his nesting territory will be fertilized by another male. d. Migration i. Behavior : Long-distance movement of a large number if individuals associated with a change of seasons– Serengeti’s Great Migration 1. Prox. Cause: a. How do animals know when to move on? b. How do they navigate? i. Visual Landmarks ii. Sun Compass iii. Star Compass iv. Magnetic Compass 2. Ulti. Cause: a. What are the benefits of multiple “homes” that outweigh the cost of long-distance travel? i. Tradeoff between energy expenditure and _____ ii. Resource (generally food) availability iii. A safe location to breed e. Foraging i. Behavior: searching for and exploiting food resources 1. Optimal Foraging Theory

2. Communication Example: The Waggle Dance a. Proximate Cause : How/what do animals communicate? b. Ultimate Cause : Why do animals communicate? 3. Define deceitful communication : a. Singaler attempts to exploit the receiver i. Examples: 1. Hognose snakes play dead to avoid being eaten 2. Female Photuris fireflies flash the courtship signal of another species and then eat males that respond. 3. Male fiddler crabs have enlarged “major” claws used in fights and to attract mates– males that lose their major claw regenerate claws that are large, but weak. ii. Success is often density dependent Living in Groups - Altruism 1. Define altruism : a. behaviors that have a fitness cost to the individual exhibiting the behavior and a fitness benefit to the receiver b. Examples: i. Cooperative breeding ii. Food sharing iii. Grooming iv. protection 2. Explain the paradox of altruism (how does it seem to contradict predictions of natural selection?): a. 3 ingredients of natural selection i. variation - some individuals behave altruistically, others don’t ii. heritability - altruistic behavior has genetic (heritable) component iii. more offspring produced than survive - struggle for existence b. Outcome : traits of individuals with higher relative fitness increase in frequency over generations. Thus, decrease of altruism alleles could be predicted 3. Define Kin Selection : a. Selection that acts through benefits to relatives at the expense of the individual

b. Explain Br > C https://www.britannica.com/science/Hamiltons-rule i. B : benefit to recipient ii. r : coefficient of relatedness 1. Measure of genetic relatedness of two individuals 2. What proportion of genes are inherited from a common ancestor (0-1.0) a. Parent-offspring: 0.5 b. Identical twins: 1.0 c. Fraternal twins: 0.5 d. Siblings: 0.5 e. Half-siblings: 0.25 f. Grandparent-grandchild: 0.25 iii. C : cost of altruism c. Compare/contrast direct, indirect, and inclusive fitness : i. Direct fitness 1. derived from generating offspring ii. Indirect fitness 1. derived from helping relatives produce more offspring than they would on their own iii. Inclusive fitness 1. Direct fitness+ Indirect fitness d. Come up with 3 scenarios (based on genetic relatedness) where helping non- offspring kin would have the same effect on inclusive fitness as 2 offspring i. Scenario 1: Supporting Siblings or Nieces/Nephews 1. Consider an individual who forgoes having their own offspring but instead invests their resources in supporting and helping raise two full siblings or four nieces/nephews. 2. In terms of genetic relatedness, an individual shares 50% of their genes with full siblings and 25% with nieces/nephews. By assisting in the survival and success of these siblings or nieces/nephews, the helper can ensure the propagation of a similar proportion of their shared genetic material, similar to what they'd pass on by having two of their own offspring.

best predictor of food donated; More important than relatedness Living in Groups - Sexual Reproduction 1. Compare/contrast intersexual and intrasexual selection : a. Intersexual Selection i. Between sexes ii. Ex. Female choice b. Intrasexual Selection i. Within one sex ii. Ex. male-male competition c. Evidence of intra- and intersexual selection in Anolis lizards i. Dewlap extension and pushups used in courtship females ii. Pushups also used as territoriality display for other males iii. Dewlap brightness is NOT correlated with nutritional health (not an honest signal of health) iv. Larger dewlaps do correlate with higher bite force (possible honest signal of male physical vigor) 2. Describe 3 different mating systems (with examples): a. Monogamous i. One male and one female are paired for at least one breeding season. ii. In some animals, such as the gray wolf, these associations can last much longer, even a lifetime. 1. The “mate-guarding hypothesis” may explain this type of mating system, stating that males stay with the female to prevent other males from mating with her. 2. This behavior is advantageous in such situations where mates are scarce and difficult to find. Another explanation is the “male- assistance hypothesis,” where males that help guard and rear their young will have more and healthier offspring. iii. Monogamy is observed in many bird populations where, in addition to the parental care from the female, the male is also a major provider of parental care for the chicks.

1. A third explanation for the evolutionary advantages of monogamy is the “female-enforcement hypothesis . ” In this scenario, the female ensures that the male does not have other offspring that might compete with her own, so she actively interferes with the male’s signaling to attract other mates. b. Polygynous i. One male mating with multiple females; the females typically take on most of the parental care due to the male's inability to support numerous offspring. ii. In resourced-based polygyny , males compete for territories with the best resources, and then mate with females that enter the territory, drawn to its resource richness. 1. The female benefits by mating with a dominant, genetically fit male; however, it is at the cost of having no male help in caring for the offspring. a. Ex. yellow-rumped honeyguide, a bird whose males defend beehives because the females feed on their wax. As the females approach, the male defending the nest will mate with them. b. Ex. Harem mating structures are a type of polygynous system where certain males dominate mating while controlling a territory with resources. Harem mating occurs in elephant seals, where the alpha male dominates the mating within the group. c. Ex. lek system. Here there is a communal courting area where several males perform elaborate displays for females, and the females choose their mate from this group. This behavior is observed in several bird species including the sage grouse and the prairie chicken. c. Polyandrous i. One female mates with many males 1. Ex. In pipefishes and seahorses, males receive the eggs from the female, fertilize them, protect them within a pouch, and give birth to the offspring. Therefore, the female is able to provide eggs to