This lab will explore the methods used by primatologists in conducting observations of various primate species. By employing systemic, ordered techniques, these scientists can produce robust data that can be compared across the field and across species. Such comparative data allow us to better understand the variation present across primates, and consider the role of our own species, Homo sapiens within the primate order.
Please read through the descriptions and activities on this page, and answer the questions on your lab answer sheet. In the first part, you’ll learn and practice the specific techniques employed by primatologists in the field. In the second part, you’ll watch the movie “Clever Monkeys” for an introduction to general primate behaviors. When finished, please submit your lab answer sheets in Blackboard.
PART 1: Primate Observation Practice
In this exercise you will observe a video and record the monkeys’ behavior. The video was recorded as part of an experiment regarding foraging and food transfer in captive golden lion tamarins (Leontopithecus rosalia) conducted by Dr. Lisa Rapaport (of Clemson University) at the National Zoo in Washington, DC. This lab activity has also been adapted from Dr. Rapaport’s work.
In the video, the tamarins search for grapes that are hidden behind the doors of a large puzzle box. It is fairly easy to determine when a tamarin has found a grape, even if the grape itself is obscured from view, because the grape is invariably eaten or passed to another tamarin. The tamarin group in the video consists of four individuals:
- Cary – slightly larger than the others, tail uniformly light colored, male
- Deena – an overall slight build, a faded broad black stripe in the middle of her tail
- Ori – a well-defined black band in the middle of the tail and near the tail tip, male
- Oops – very short tail, female
One of the narrators constantly apprises the viewer as to the identity of the tamarins, so keep the sound on as you watch the tape.
Before beginning observations, a list of carefully defined behaviors, or an ethogram, must be devised. The behaviors in the ethogram below are mutually exclusive, i.e., a tamarin cannot be engaged in more than one behavior at a time. Before beginning this exercise, read through the Ethogram to familiarize yourself with the terms.
Method 1: Instantaneous Sampling
In this sampling method, the observation session is divided into short sample intervals. The observer writes down what the focal animal is doing at the beginning of each sample interval.
Our sample interval will be 30 seconds, and we will record the behavior of each individual in the group, using the spreadsheet below. The idea is to take a mental snapshot of an individual’s behavior at the instant each interval begins. To assist the observer, instantaneous sampling is used in conjunction with an audible “beep” to alert the observer as to when to take a mental picture of the animal(s) behavior. You will choose one primary tamarin to observe for your observation practice.
Use the abbreviations: they cut down on time spent looking at the paper rather than at the monkeys and what they are doing.
Use the embed above, or this link to access the Golden Tamarin observation video: https://sc.kanopy.com/video/golden-lion-tamarin-data-collection-exercise. It may bring you to a page that says access denied; where you see the option to log in to kanopy you can just use your USC library log on information. Once you are logged in, if you receive a message that the video is password protected, enter the password: ANTH161FA20.
Watch the Golden Tamarin observation video, and fill out the table below, focusing on one individual of your choice. You will hear a beep in the video that will sound every 30 seconds. Using the ethogram, write the code for the behavior that individual is doing at the time of the beep. After you watch the entire video (5 minutes) for one focal individual, repeat for the remaining three, watching at least half-way.
Calculate a time budget for each individual in the table below. That is, what proportion of intervals did each individual spend in each behavior?
Method 2: Ad libitum (diary entry) sampling
This is a continuous method that requires the observer to record essentially all the behaviors of a group during a specified period of time. Practically, this means surveying the group as a whole, and noting times at which activities occur.
Rewatch the same Golden Tamarin observation video. This time, you are going to pay attention to all of the individuals. As you’re watching, write diary-style observations of the entire group. In the space below, note the behaviors and interactions of all four members during the 5 minute clip.
Reflection Questions Comparing the Sampling Methods
- Which of the two methods (ad lib and instantaneous) provides the best assessment of getting grapes? Why?
- Which behaviors did you record in Method 2 (ad lib) but not in Method 1 (instantaneous) for your group’s focal animal?
- Are there differences in the kinds of behaviors observed in the two methods? What types of behaviors are likely to be underrepresented by the Instantaneous method compared to the diary method? Why?
- What are the advantages and disadvantages of Instantaneous sampling versus ad lib sampling?
- The number of food items transferred to others is one measure of generosity. What would be the best method to use for this measure?
- Is this “method” referring to instantaneous/ad lib or is it in regards to the behavior codes? (ex: FT) Maybe clarify this question?
- A comparison of food-capture frequency over time spent eating ( ) is another measure of generosity. According to this measure, who is the most generous?
- In what other way(s) might one measure generosity in these tamarins?
PART 2: Primate Behaviors
Below is a link to the Nature film Clever Monkeys, narrated by David Attenborough. This film presents a range of different monkey species. In the space on your answer sheet, note the various species present, and list the kinds of behaviors in which they engage. What observations can you make about culture among monkey groups? In the past, some students have had issues with the link below in some specific browsers. I have just confirmed that it works fine in Chrome.
Altmann, J. (1974). Observational study of behavior: Sampling methods. Behavior, 49, 227-267.
Martin, P., & Bateson, P. (2007). Measuring behavior: An introductory guide. 3rd edn. Cambridge: Cambridge University Press.
Rapaport, L.G. (1998). Optimal foraging theory predicts effects of environmental enrichment in a group of adult golden lion tamarins. Zoo Biology, 17(3), 231-244.