Exam 1 Flashcards
Types of Hypothesis
Research, Alternative, Null
Alternative Hypothesis
Statistical hypothesis that the explanation is significant
Null Hypothesis
Statistical hypothesis that the explanation is not significant
Robin Hypothesis Example
Yards with more food have more robins. (Alternative and Null Hypotheses: The amount of worms does/doesn’t determine the number of birds)
Directional hypothesis
Alt hypothesis predicts in which direction the dependent variable will be affected (positive or negative correlation)
Proximate mechanisms
Immediate cause and development of behavior: Neural, sensory, internal mechanisms
Ultimate reasons
Evolutionary causes of behavior: Happens after the behavior, an increase in chance of survival
Tinbergen’s four questions
Mechanisms (proximate & current), development (proximate & over time), function (ultimate & current), & evolution (ultimate & over time)
Hans the Horse Example
Claimed he was able to do mathematics, found that the trainer would cue the horse to stop stomping when he got to the right answer
Darwin
First one to bring adaptation theory into the explanation of speciation
Cuckoo & Warbler Example
Brood parasitism behavior, animals evolve behavior (instincts) that increase their own fitness, not learned
Classical ethology
Understanding species behavior of wild animals by experimentation and observation, claim that behaviors work the same as evolved physical characteristics
Fixed Action Pattern
Each species has a fixed set of behaviors that are not learned
Key stimulus
The ‘key’ to activate the fixed action patterns
Digger Wasp Example
(Tinbergen) Fixed action pattern called orientation flight, key stimulus is light.
Geese Egg Rolling Example
Key stimulus is egg rolling, movement is a fixed action pattern, completes action even if egg is removed
Herring Gull Chick Example
Key stimulus is shape patch with high contrast, fixed action pattern is pecking to ask for food
Stickleback Example
Key stimulus is red lower body, fixed action pattern is aggressive male attack behavior
Behaviorism
Branch of psychology, emphasis on learning theories, studies behavior independent of animals’ mental states / consciousness (Skinner and Pavlov)
Skinner
Extreme environmentalist (everything is a result of environment), ignored biology, substituted humans with animals to study behavior ignoring species differences
Pavlov
Conditioning behavior, occurs when novel stimulus is paired with an existing stimulus
Evolutionary psychology
Understanding human thinking and behavior in terms of natural selection
Behavioral ecology
Study of the evolution of behavior based on fitness
Guilty Dog Example
(Avoidance of anthropomorphic explanations) The owner tells the dog not to eat and leaves.
See if the dog has a guilty submissive posture after eating without permission. Guilty behavior shown based on the owner’s response to the dog, not actual guilt.
Wolf Spider Example
Question: How do male wolf spiders find unmated female spiders?
Tapping behavior is advertisement behavior by the male, signaling to attract females. Strategy where the males listen to other males; if there are other males tapping, there is likely a female nearby; conserves energy.
First experiment led to null hypothesis; second experiment was done with grown spider who had prior social interactions and it supported the new hypothesis.
(Shows example of hypothesis based research)
Tungara Frogs Example
The second sound is a better signal for females, however the frogs do not use it as often. Bats try to locate the frogs by the second sound.
(Shows that observation is important for hypothesis generation)
Squirrel and Hawk Example
Mathematical model to predict behavior. Finding what food the squirrel will go for based on distance from safety (tree)
Methods to study behvaior
Observational, experimental, comparative
Sheep Mating Example
Observational method
Either guard a ewe (tending) or chase guarded ewes (coursing).
There was not a difference between the two groups in the amount of time spent foraging.
Naiads & Tadpoles
Experimental method
Naiads have a long digestive organ that can take in water and eject it for jet propulsion. Jumping tadpoles: if there is a dragonfly nymph, they jump out of the water.
Put an object in the water for a predator control treatment.
In presence of the predator, the tadpole jumped. In presence of predator control, there was only a tiny increase in jumping compared to the control.
When a mesh is put over the dish, the survival of the tadpoles decreases.
Deer Mouse Example
Comparative method
Evolution of burrowing behavior: Phylogenetic tree shows the evolutionary relationship of different species of mice.
The creation of an escape tunnel while burrowing is a derived trait by the deer mouse.
Sheldrake and Mallard Duck
Comparative method
Inciting behavior: threatening behavior where the female points out another male to a potential mate with her beak, asking him to attack the other duck.
In mallard ducks, the beak direction doesn’t always point towards the enemy; they make a head movement asking to attack nearby male without pointing directly towards the enemy
Ritualized meaning of behavior: the meaning of the behavior has changed
The sheldrake duck has the ancestral behavioral trait, the mallard has a derived trait
Dog and European Bullfinch Scratching
Comparative method
For dog, scratching is a natural movement. The natural movement for birds is to scratch their head by stretching their leg underneath their wing up towards their head. However, most birds stretch their leg around their wing instead, can only be explained by evolution.
Darwin’s conditions for natural selection
Variation is the basis of evolution.
Traits are partially heritable. Traits can be passed from parent to offspring.
Traits confer differences in survivorship and reproductive success; fitness
Reasons for the existence of variation
Genetic composition differences; Recombination
Differences in environmental conditions
Frequency-dependent selection
Differences in learned behaviors (doesn’t cause evolution)
Lack of variation in fitness (doesn’t cause evolution)
Fishers vs. Pirates Example
Frequency Dependent Selection
Fisher birds hunt, pirate birds steal
If almost everyone is fisher, then pirates are successful, and population of pirates increases
If most are pirates, then there are less fishers, and the pirates are unsuccessful
Evolutionarily Stable Strategy: maintains variation at a ratio
70% fisher / 30% pirate
Salamander Example
Frequency Dependent Selection
Two clay models, one is striped and one is not. They both have peanuts attached to them.
Testing for why the two variations exist, recording attacks on them by birds and mammals.
When the phenotype is rare, they are advantageous
Fitness is number of peanuts preserved per model
How to test heritability
Parent-offspring regressions and selection experiments
Selection experiment control is random breeding, compare it to selective breeding results
Regression line is a correlation line, slope indicates the degree of heritability
Measures of Fitness
Number of viable offspring
Indirect:
Number of mates, survivorship, # offspring, size, feeding rate, growth rate
Male Bluegill Sunfish Example
Frequency Dependent Selection
Parental males: work to attract females and mate (courting, nest building, large size)
Satellite males: look and act like females, secretly inseminates eggs
Sneaker males: very small, sneak into parental male nest and inseminate eggs
3 Modes of Natural Selection
Directional, Disruptive, Stabilizing
Tadpole Disruptive Selection Example
Spadefoot toad tadpoles have either small or large mouths. The detritivores consume detritus and small invertebrates. The carnivores consume invertebrates. Intermediates can eat both, but their fitness is lower because their mouth is the wrong size for both specializations.
Cichlid Stabilizing Selection Example
Defend territory to secure food. Large territory is harder to defend. When placed in an aquarium with different patches of food, the ones that defended medium sizes of territory had the highest fitness.
Levels of Natural Selection
Genes, individual, groups, species
Excepted answer is mostly individual, sometimes group (altruism and eusociality)
Kin selection
Individuals increase their fitness by helping close relatives
Kin selection theory = inclusive fitness theory
Inclusive fitness
Individual + kin fitness
Multilevel selection
Both individual and group selection
Eusociality
Reproductive division of labor into breeding and nonbreeding castes, cooperative care of young, part of group selection
Who proposed the idea of inclusive fitness?
Hamilton
Sexual selection
Happens to traits that are specific to males or females
Includes mate selection
Difference between natural and artificial selection, selective breeding =/= sexual selection
Fox Domestication Example
When he put food out for a fox, he recorded how close the fox was willing to come to the human
Control and selected foxes were raised the same way
After selecting for 45 years, he created a very tame fox
Measured to see if the fox would follow pointing
Looking at selected fox cognitive behavior gives insight about possible history of domesticated dog selection
Fear and aggression depend on neurotransmitters, the neurotransmitters change during domestication
Dog Toy Experiment
Two identical toys
Human plays with one of the two
Measure which one the dog touches, see if the dog goes for the one touched by the human
When one toy is touched with a feather and not by the human, the dog does not have a preference
