Chapter 1- Principles of animal behavior

Question 1

Scientific method

Answer 1

Scientific observation, measurement, and experiment, as well as the formulation, testing, and modification of hypotheses.

Question 2

Hypotheses

Answer 2

Predictions of the outcome of an experiment based on observations

Question 3

Ethology

Answer 3

The study of animal behavior. Most people have some understanding of animal behavior, and understanding of animal behavior appears to have been important to ancient civilizations, as animals were often featured in ancient art.

Question 4

Aristotle

Answer 4

A naturalist who wrote books about animals. His books Physics and Natural History of Animals distinguished between hundreds of species of animals and described animal behavior.

Question 5

Ethology combines which other fields of science?

Answer 5

Evolution, learning, genetics, molecular biology, development, neurobiology, and endocrinology.

Question 6

4 types of questions about how to study behavior

Answer 6

1. Mechanistic
2. Developmental
3. Survival value
4. Evolutionary history

Question 7

Mechanistic questions

Answer 7

Asks what stimuli causes this behavior. What changes are occurring in the body in response to this stimuli? Includes changes in hormones, neurotransmitters, and brain connectivity.

Question 8

Developmental questions

Answer 8

Asks if this behavior is the same as the organism ages. Is it seen at all ages, or to the same extent at all ages? Sexual behavior is an example of a behavior that generally develops after puberty, later in an animal’s lifespan.

Question 9

Survival value questions

Answer 9

Is this behavior necessary for survival, and does it increase the likelihood of successful mating?
For peacocks, males have large, colorful tails. This puts the males at greater risk because they are more likely to be seen by predators. However, the tail is necessary for reproduction, so it does have survival value

Question 10

Evolutionary history questions

Answer 10

How does the behavior change from the viewpoint of phylogeny? Phylogenetic trees are used to study this- at what point in evolutionary history was this trait added?

Question 11

Phylogeny

Answer 11

Evolutionary history

Question 12

Proximate analysis

Answer 12

What are the immediate causes for the behavior?
Hormones, neurotransmitters, fear response are examples of causes. This analysis occurs at the level of the animal. Includes mechanistic and developmental questions.

Question 13

Ultimate analysis

Answer 13

Focuses on the evolutionary forces that have shaped this behavior over time. Occurs at the level of the species. Includes survival value and evolutionary history questions.

Question 14

Behavior

Answer 14

Dugatkin- the coordinated responses of whole living organisms to internal and/or external stimuli. This definition captures what most modern ethologists and behavioral ecologists mean when they use this term.

Question 15

On the Origin of Species

Answer 15

Written by Charles Darwin. Described how evolutionary change has shaped the diversity of life, and how natural selection is the driver of that change.

Question 16

Natural selection

Answer 16

Proposed by Darwin. The process where traits that give an individual a reproductive advantage are selected for and increase in frequency in future generations. He argued that any trait that was both heritable and provided an animal with some sort of reproductive advantage over others in its population would be favored by natural selection. Infants are born with several naturally selected behaviors such as suckling. Giraffe neck length example- giraffes with longer necks were able to access food more easily, so they survived more frequently and this trait was selected for.

Question 17

Individual learning

Answer 17

Alters the frequency of behaviors exhibited during an organism’s lifetime. Asks how new information is processed and used. This is studying learning from a proximate level of analysis. Animals learn about many things, like food, shelter, and predators. Rabbit example- the rabbit learned how to herd sheep- this behavior would not have been selected for.

Question 18

Learning from an ultimate perspective

Answer 18

When we study how natural selection affects the ability of animals to learn, we are approaching learning from an ultimate perspective. We could assess how an animal’s ability to learn impacts its reproductive success.

Question 19

3 foundations of behavior

Answer 19

This describes ways to explain how behavior came about
1. Natural selection
2. Individual learning
3. Cultural transmission

Question 20

Cultural transmission

Answer 20

A transmission system in which animals learn through various forms of social learning. Allows newly acquired traits to quickly spread through a population, as well as transmission of generations across generations within a species. Natural selection and individual learning can act on animals’ ability to transmit, acquire, and act on culturally transmitted information.

Question 21

Morphological traits

Answer 21

Changes to the outward appearance of an animal as well as the form and structure of internal parts, like bones and organs. Morphology and behavior are often linked.

Question 22

Cricket example of natural selection (Zuk study)

Answer 22

Male crickets sing in order to attract mates. Although the songs attract female crickets, they can also attract predators. On one Hawaiian island, the songs attracted parasitic flies that would kill crickets. Researchers found that “flatwing males” who were not able to sing became prevalent in that cricket population. This is likely due to natural selection, but it’s unclear how the trait provides a mating advantage. They used playback experiments playing male cricket songs for the cricket subjects. It seems that flatwing males stay near singing males and mate with females as they approach the singers.

Question 23

Convergent evolution

Answer 23

On another Hawaiian island, male crickets exhibited an independent but parallel evolution of the flatwing trait.

Question 24

Xenophobia

Answer 24

A fear of strangers. For animal groups, strangers may pose a threat by competing for resources or disrupting group dynamics.

Question 25

Why should xenophobia be sensitive to the sex of a stranger?

Answer 25

Mole rats sometimes leave their home colony in order to find a mate. Therefore, strangers of the opposite sex could be a potential mate and be worth tolerating.

Question 26

How can individual learning affect mating behavior?

Answer 26

One example is of birds. A female bird might mate with different males over time and keep track of the number of eggs she laid after mating with each male in order to determine who is a better mate. In this case, learning affected mating behavior within a generation, but natural selection can operate on the ability to learn. Natural selection could favor the ability to tell which males are good mates, for example.

Question 27

Learning in insects study (Dukas and Bernays)

Answer 27

*Goal- examining the fitness related consequences of learning in the grasshopper
*Background- some foraging behaviors in grasshoppers are learned.
*Method- grasshoppers were given one balanced diet dish (proteins and carbs) and one deficient diet dish (no carbs). Diets were paired with specific odors and color cards as cues in the learning group. The cues were randomly assigned for the nontreatment group.
*Results- learning treatment grasshoppers ate more food from the balanced diet dish. Both groups increased their proportion of time eating the balanced diet, but the learning group did so more quickly. The learning group had a higher growth rate
*Explanation- the increase in growth rate translates to greater reproductive success. This is the fitness benefit

Question 28

Foraging behavior in rats (Salek)

Answer 28

*Goal- how cultural transmission influences foraging behavior in rats
*Background- a new food source could be dangerous. Rats may be able to tell whether a food source is safe by interacting with others that have returned from foraging.
*Method- rats divided into observer and demonstrator groups. A demonstrator rat was removed and given one of two novel diets- rat chow with different flavorings. Demonstrators and observers were allowed to interact for 15 minutes after the demonstrator ate.
*Results- after interacting with their tutor, observer rats were more likely to use olfactory cues to eat the same food their tutors had eaten.
*Explanation- the results demonstrate cultural transmission

Question 29

Approaches to ethology (3)

Answer 29

1. Conceptual
2. Empirical
3. Theoretical
   A study could use a combination of these approaches

Question 30

Types of empirical studies

Answer 30

Observational and experimental

Question 31

Fitness

Answer 31

A concept, defined as the individuals’ reproductive success. Fitness is different from one species to another- some species have longer lifespans and have less offspring, but are able to care for the offspring into adulthood. This is a different fitness concept. Some individuals might not have offspring, but could care for their nephews and nieces for example. Their genes are still being passed on and they are helping their nephews and nieces to survive. This is indirect fitness.

Question 32

Conceptual approach to ethology

Answer 32

Involves integrating unconnected ideas and combining them in new, cohesive ways. Experimentation can play a role in concept development, but a concept isn’t tied to one specific experiment. Kin selection is one example of a concept that changed the way we look at natural selection- demonstrated that natural selection also favors behaviors that increase the reproductive success of those individuals’ close genetic kin.

Question 33

Kin selection

Answer 33

Natural selection also favors behaviors that increase the reproductive success of those individuals’ close genetic kin. Hamilton proposed that fitness is composed of both indirect and direct fitness

Question 34

Direct fitness

Answer 34

Measured by the number of viable offspring produced, and any effects that an individual might have on the descendants of its own offspring (like grandkids).

Question 35

Indirect fitness

Answer 35

Measured by the increased reproductive success of an individual’s genetic relatives- not including their offspring or descendants of their offspring- that are due to the individual’s behavior. These actions indirectly get copies of the individual’s genes into the next generation.

Question 36

Inclusive fitness

Answer 36

The sum of an individual’s direct and indirect fitness. An individual might help their parents to raise more siblings than the parents would have been able to take care of themselves.

Question 37

Theoretical approach to ethology

Answer 37

Generates a mathematical model of the world, which might not relate to the real world perfectly. This approach can be related to foraging behaviors in order to determine which food items an animal should add to its diet, and under which conditions. This question was answered using optimality theory, which searches for the best solution to the problem.

Question 38

Optimality theory

Answer 38

Searches for the best solution to a specific problem, given that certain constraints exist. A model that examines how animals choose which prey to add to their diet might be concerned with the amount of time an animal has to search for food, the energy provided by the prey, the time it takes to eat, and the rate at which prey is encountered. All these factors would be treated as variables that could be used to examine how they affect foraging decisions animals make. These theories can generate multiple predictions, some of which are contradictory.

Question 39

Modern ethological experimentation is often associated with which 3 Nobel prize winners?

Answer 39

von Frisch, Niko Tinbergen, and Konrad Lorenz- all were naturalists who asked important questions about animal behavior. These questions could be addressed by a combination of observation and experimentation.

Question 40

Observational studies

Answer 40

Gathering data about animals’ behavior without manipulating or controlling an ethological or environmental variable. An example would be going to a marsh and recording birds’ behavior over a specific time interval. You could make hypotheses about the birds’ behavior from your observations.

Question 41

Experimental studies

Answer 41

Independent and dependent variables- manipulating one variable and measuring the changes in the other. This is the only type of study that allows for causal claims. If two variables are correlated, the data is not sufficient to make a causal claim.

Question 42

Does theory come before or after empirical work?

Answer 42

It depends- a theory can come before or after collecting data. An observation or experiment might suggest that the results call for a mathematical model to be developed. However, models can also inspire empirical studies. There is generally a feedback loop between advances in theoretical work and advances in empirical work.

Question 43

Spinks xenophobia study

Answer 43

*Goal- to examine the connection between xenophobia and resource scarcity. *Background- populations differ in terms of resource availability, and most mole rats in a population are genetic relatives. Mesic (moist) environments have greater resource availability.
*Method- one mole rat from an arid environment and one mole rat from a mesic environment were placed together and aggression was recorded.
*Results- when the pair was both male or both female, aggression was greater in the arid environment individuals. When two individuals from an arid environment knew each other, aggression disappeared- identification of a stranger caused aggression.
*Explanation- natural selection favors stronger xenophobic responses that are sensitive to sex, as most mole rats leave home to find a mate.