I. INTRODUCTION

Several themes were presented in the beginning of the course related to the complexities of studying animal behavior. It is now time to come back to those themes to provide a final perspective and review of the material covered in this course. We will once again consider why animal behavior is more than mere description and why it can be so difficult to understand. To come full circle, we will discuss the following points and add examples from the material presented over the last 4 months.

A. Animal Behavior defined as: the scientific study of how and why animals act as they do

B. Different questions about behavior

1. Immediate Causation

2._________________

3._________________

4. Evolutionary history

C. The Paradox -

1. observations may be relatively simple

2. explanations for how and why animals do what they do can be very complex

D. An appreciation of the complexities

1. Different levels of analysis (related to the different questions about behavior)

2. _______________________

3. _______________________

4. Anthropomorphism

II. SCIENTIFIC STUDIES

A. The Scientific Method

1. proceeds by asking a question, developing a hypothesis, determining the prediction(s) that follow from the hypothesis, testing the predictions and drawing conclusions.

2. An important point is the distinction between hypothesis and prediction:

a. A hypothesis is ______________________________________

b. A prediction is _______________________________________

B. Observational methods are required to collect the data. Such methods include vantage point, category construction, measurement of those categories, subject sampling and time sampling.

III. FOUR BIOLOGICALLY RELEVANT QUESTIONS

A. How or Proximate Questions

1. The first question concerns __________________________ (many studies over the semester have addressed the notion of underlying mechanism)

b. How do bees use dances to communicate the location of food sources? (controversy between Wenner and Von Frisch over the role of dances and olfaction)

c. What cues do homing pigeons use to get to the home loft?

d. What cues do mallee fowls use to determine the incubation strategy?

2. The second question concerns ___________________________

b. How does mother-infant interaction change as a function of age in rhesus monkeys?

 B. Why or Ultimate Questions

1. Functional Significance (an understanding of how behavior promotes reproductive success)

Primary helpers are relatives and gain indirect fitness benefits by foregoing reproduction to help rear brothers and sisters.

Secondary helpers gain __________________fitness benefits in the 2nd year of life because they had an increased likelihood of finding a mate (often the parent they helped in their first year of life).

b. Egg shell removal in the black headed gull

Black headed gulls, but not kittiwakes (another gull species), remove egg shell fragments from their nest. It is energetically costly to pick up fragments and carry them some distance from the nest. Furthermore, it takes the parents away from the nest. Tinbergen asked why do gulls remove egg shell fragments?

Tinbergen tested the hypothesis ______________________________

c. Color adaptations and antipredator behavior

Pinehawk moths and other cryptic moths appear to seek out particular kinds of trees (different trees for different species) and then rest on the bark in a particular orientation. Presumably, these behavioral responses make the moth cryptic to predators. This assumption was tested by using blue jays (a moth predator) and operant chambers.

d. mating behavior in bowerbirds

Satin bowerbirds have a strange mating ritual which involves the construction of bowers, the collection of blue decorations, and the exhibition of highly aggressive and noisy mating displays. One possible explanation for this ritual is good genes. Males that successfully maintain their bowers and hold on to their decorations are older and more dominant. Females may be able to identify good genes by the presence of large pile of decorations and a sturdy well constructed bower.

Successful males were those that modulated their responses to females

2. Evolutionary History

III. THE PARADOX OF BEHAVIOR

A. Simple but extraordinarily complex

1. Animal behavior is simple to describe but it can be a real challenge to explain.

2. There are concepts that seem easy but require an understanding of statistics and mathematics

b. Inclusive fitness (a common error is to count all the offspring helped and assign them to the helper. The only offspring that can be counted for the helper are the extra offspring that are above and beyond what the animal could have reared on its own).

c. Learning and species differences - We learned that measures can sometimes be problematic. If we are interested in comparing cognitive capabilities in two different species (e.g., do chimpanzees and rhesus monkeys have self recognition?), we have to understand the limitations of such comparisons.

Learning can't be measured directly. We can only assess it through __________________.

However, performance can be affected by variables other than cognitive capability. We term these other variables ______________________________

d. Gene-environment interactions - that behavior is not a function of either genes or environment but is subject to the complex interaction between both. Rhesus monkey mothers respond differently to infants based on their sex. This differential reaction is controlled both by maternal environment (the mother's response) and genes (individual differences in male and female infants).

e. The Runaway selection model -

 

f. Polygyny threshold - Mating systems can vary within the same species. Redwing blackbirds, for example, can be either monogamous or polygynous. Female redwings choose males on the basis of quality of the territory. High quality territories are in short supply, and thus females may have to choose between mating with an already mated male on a high quality territory (polygyny) as opposed to mating with an unmated male on a poorer quality territory (monogamy). The polygyny threshold refers to the difference in territory quality needed for a female to do better from a fitness perspective by mating with an already mated male compared to an unmated male.

B. Some reasons for the Complexity

1. Different Levels of Analysis

1. Migration was studied in terms of causation or underlying mechanism (piloting, compass orientation or true navigation). It was also studied in terms of function (why do migrants return - longer days hypothesis)

2. Communication was studied from two perspectives. The structure of communication was examined in the crying wolf study (vervet monkeys). A study of alarm calls in Belding's ground squirrel revealed their function. Ground squirrels produce different types of vocalizations in response to aerial vs. terrestrial predators.

3. Models of parental behavior also represent different levels of analysis. The symbiotic model assesses the causal and developmental connections between mothers and infants. Mothers provide pups with milk and regain some lost fluid through consumption of pup urine. The parent-offspring conflict model examines the benefits and costs of the weaning conflict in terms of how it differentially promotes reproductive success in infants and mothers.

b. related to the environment in which the study occurred (at its very simplest, field vs. lab)

2. Multiple Causation

b. Optimal foraging models start with an examination of energy gained and lost. Crow foraging behavior can be simply understood from an energy perspective model. However, other species do not follow a simple energy model and other factors need to be added to the equation - leading to the notion that many factors contribute to foraging behavior - e.g., toxicity of leaves in howler monkeys; use of social information in ospreys.

c. Homing pigeons can use several cues to get to the home loft. These include solar, magnetic, and olfactory cues.

The challenge is ______________________________________________________________________

 3. Species Diversity

b. This notion also applies to closely related species.

1. Voles within the genus Microtus show major differences in pair bonding and offspring care? Prairie voles are monogamous and both male and female provide extensive care to pups whereas meadow voles show a form of scramble competition. There is no bond and males do not care for pups.

2. Some gulls remove egg shell fragments (e.g., black headed gull) whereas other gulls do not (e.g., kittiwake). Furthermore egg shell removal can occur in other unrelated birds that nest on the ground (e.g., bittern)

 c. Thus, one must be careful about generalizing the findings of one species to a particular taxonomic genus or family

 4. Anthropomorphism