Lab 11 Sociograms Handout Spring 2021

ANTH 2764 Spring 2021 Methods in Primate Ethology – Sociograms Name: Lauren Severe Lab 11: Sociograms In past labs, we have constructed ethograms to be used in behavioral data collecIon and we have observed dyads . In this lab, we will analyze a data matrix to construct a sociogram . A sociogram is a sociometric diagram represenIng the paMern of relaIonships between individuals in a group, usually expressed in terms of which individuals they prefer to associate with. In other words, a graphical representaIon of behavioral interacIon data. In this exercise, hypotheIcal dyadic interacIon data from a capIve populaIon of Rhesus Macaques is illustrated below. The group consists of adult males Rick and Glenn, adult females Beth and Maggie (who are sisters) and Sasha (a cousin to the sisters), and sub-adult male Carl. 1. Who receives the most grooming overall? The least? Why might this be? - Rick receives the most grooming overall, while Carl receives the least amount of grooming. This might be because Carl is not an alpha male or because he was an outsider to the group/ newly added to this group. Carl could have definitely come in from another group while Rick was already in this group, allowing him to be the most groomed. 1

ANTH 2764 Spring 2021 Methods in Primate Ethology – Sociograms Name: Lauren Severe 2. Who provides the most grooming overall? The least? Why might this be? - Maggie provides the most grooming overall, while Sasha provides the least grooming. This might be because Maggie is an adult and might have her own children, and Sasha could be younger causing her to groom the least amount. Another reason that this might be is because Maggie has a lot more close family in this group than Sasha does. Sasha is just a cousin to the sisters and has less Fes to the monkeys than the sisters do. 3. Using the data given on page 1, calculate the relaIve frequency (%) of grooming events for each dyad. • You DO NOT have to show your work; just the percentage is fine. Gro om er (Ac tor ) Rick Glenn Maggie Beth Sasha Carl Total Rick 4/260 = 0.015*100 = 1.5% 1.2% 8.5% 2.7% 1.2% 13.6% Glenn 5.8% 4.2% 0% 2.7% 0.4% 7.3% Maggie 5.0% 6.2% 5.8% 3.1% 1.2% 21.3% Beth 11.2% 0% 3.8% 2.3% 1.2% 18.5% Sasha 4.6% 1.2% 1.2% 4.6% 0.4% 12.0% Carl 5.8% 4.6% 3.1% 5.8% 5.0% 24.3% Total 32.4% 13.5% 13.5% 24.7% 15.8% 4.4% 260/260 = 1.0*100 = 100% 2 Groomee (Recipient)

ANTH 2764 Spring 2021 Methods in Primate Ethology – Sociograms Name: Lauren Severe Key: = lightly groomed = heavily groomed = relaIve blue circle= male orange circle= female 5. Based on the sociogram, what can you hypothesize about the social structure of the group? • Remember, structure includes dominance hierarchies and affiliaIons, among other paMerns of social relaIons. I can hypothesize that Rick is most likely the alpha male, because he gets groomed by almost everybody. Rick also might have a strong connecFon to Beth, because they groom each other at a very high rate. Beth and Glenn do not groom each other at all. This might be because they have a problem with one another. Glenn and Beth’s sister, Maggie, seem to be very friendly as they both groom each other heavily. Also, everyone seems to groom Carl. I think this might be because he is the youngest out of the group. The cousins Sasha & Maggie seem to get along well because they equally groom each other. One thing that I have noFced within this group is that the males seem to get a lot more grooming than the females do, which we see very clear in the sociogram. 6. What aspects of social organizaFon in a macaque group might explain the high frequency of grooming between some individuals? Being the alpha male or being younger than the other macaque’s in the group might explain the high frequency of grooming between certain individuals. Another reason might be that two of the individuals are maFng, so they are grooming each other more than others in the group. 4