My Senior Thesis Project

 

My Senior Thesis Project

 

One of the biggest highlights of my time at UC Berkeley and of my career, was being able to conduct research with monkeys and lemurs at the Oakland Zoo, which I formed my senior honors thesis on. During the process, I actually kept a blog: https://primatecognitionproject.blogspot.com/, but will summarize it here as well as provide the link to my presentation on it.

Red-tailed monkey at the Oakland Zoo, by Steven Gotz.

Ring-tailed lemurs at the Oakland Zoo, by me.

Female crowned lemur at the Oakland Zoo, by me.

Male crowned lemur at the Oakland Zoo, by me.

My little SURF bio.

                     

Here is the abstract of my thesis, and of course, if anyone is interested in reading the whole thing, I would be happy to email it to you, or you can find it in the UC library system!

 

Abstract:

While primate cognition and intelligence are well-researched subjects in haplorrhines, comparatively little has been done with primates more distantly related to humans, like strepsirrhines. Overall, less research and attention has been given to these primates, such as lemurs (Bezanson & McNamara, 2019). Due to their more primitive and ancient divergence, it is often assumed that lemurs are comparatively less intelligent and cognitively capable than Old World monkeys (cercopithecoids), who are more closely related to great apes, and thus humans. Yet despite their ancient divergence, many species of lemurs have displayed equal capabilities in many areas as Old World monkeys, and are even capable of social learning, which is theorized to have led to humans’ remarkable cognitive advances (Fichtel et al., 2020) (Kendal et al., 2010) (Kappeler, 1987) (O’Mara & Hickey, 2012). 

This thesis investigates the assumption that Old World monkeys are more cognitively capable than lemurs through a comparative observational analysis and testing of a sample of red-tailed monkeys (Cercopithecus ascanius), and ring-tailed (Lemur catta) and crowned lemurs (Eulemur coronatus) in captivity at the Oakland Zoo. Two different types of containers were presented to the animals, and their cognitive abilities were inferred from factors such as: 1) how long the animals took to explore and open the new stimulus, 2) how long it took them to figure out which type had food inside, and 3) how long it took to apply what they remembered and learned after a period of absence from the containers. Results showed that there was little overall difference in all three species’ success at obtaining the food rewards, and in the proportion of their interactions between blue and yellow boxes. Both groups of animals, the two species of lemur and the red-tailed monkeys, performed on par with one another — getting better at the task over time and successfully remembering and figuring out which boxes would yield a food reward. Ultimately, this study highlights the problems in our assumption that intra-primate proximity to humans corresponds neatly with intellectual abilities. 

The primate family tree.

 

Count of publications testing primate cognition in a social setting, by species, with one entry per unique combination of environment type and species per publication. (Figure retrieved from Cronin et al., 2017. https://peerj.com/articles/3649/). 

Species represented in field primatology publications 2011–2015. Top 10 species represented by species-specific silhouettes labeled with number of field visits: Pan troglodytes, Macaca fuscata, Macaca mullata, Alouatta palliata, Alouatta pigra, Gorilla gorilla, Cebus capucinus, Papio hamadryas, Ateles geoffroyi, Lemur catta. All other species are represented by dots, the size of which reflects the number of field visits. In all, 240 species were examined in 876 field visits. (Figure retrieved from Bezanson, et al. 2019). 

This project was definitely some of the hardest/time consuming work I've ever done, but at the same time, some of the most fulfilling! I had a lot of help from the SURF fellowship, and my graduate student mentor, which I will always be so grateful for.

Crowned lemur interacting with a box during my study.

Ring-tailed lemur interacting with a box during my study.

Red-tailed monkey interacting with a box during my study.

Two ring-tailed lemurs during my study, one interacting with a box.

One of the things I learned during this process, was how to write a grant research proposal. For those interested, here is what I submitted that got me my fellowship and funding:

Undergraduate Research Project Proposal 

In the realm of animal science and primatology, it is generally considered that haplorrhine primates possess greater cognitive abilities than strepsirrhines. For my research project, I would like to test the cognitive powers between a sample of Old World monkeys (likely Red-tailed monkeys, Cercopithecus ascanius) and lemurs, specific species to be decided, but to include ring tails (Lemur catta). My research sponsor is Professor Terrence Deacon, Ph.D, an esteemed neuroanthropologist at my university.

 

Methods 

Over the course of the summer, cognitive abilities of the animals such as adaptability, learning ability, memory, and shape/type/color recognition would be inferred from: 1) The amount of time taken to investigate the new stimulus of containers in the environment and discover that they hold food. 2) The amount of time it takes for the animals to open the next container(s) after the first have been breached. 3) After a period of absence from the stimulus, the time in which it takes the animals to investigate and open the containers again. 4) In a separate session(s) from steps 1 and 2 and 3: the amount of time it takes for the animals to learn, if they do, that only certain types of container(s) hold food, based on how many of these containers versus empty containers they open. 5) In a separate session(s) from steps 1, 2, 3, and 4: after a period of absence, the amount of time it takes the animals to open the containers, and remember, if they do, that only certain types of containers hold food. 

Both the lemurs, and the Old World monkeys would be exposed to these steps, in separate sessions from one another as they are housed in different habitats. I would be observing the animals’ and recording video of the sessions. The first week of the project would be spent doing baseline observations of the animals’ natural behavior.

 

Materials: 

I would consult with the animals’ caretakers on the materials to be used for the containers, keeping in the highest priority safety. Containers would be selected with the animals’ abilities and dexterity in mind. As such, containers may vary between the lemurs versus Old World monkeys. Examples of potential containers would be wooden or metal containers, easter eggs, and wooden, cardboard, or metal boxes. A combination of types and sizes may be used, and non-toxic paint may be used to paint some or all of the containers for the Old World monkeys if determined appropriate by the animals’ caretakers. The containers would be filled with the favorite food specific to animal species’ being observed. This would likely be fruits such as bananas, figs, mangos, or apples. 

Video recordings would be taken using my GoPro, and my Canon Rebel T6i set on a tripod. Another person may be employed to help record video. Notes and data would be entered electronically using my iPad and MacBook Pro computer. Time would be kept using a stopwatch or equivalent tool. 

Results: 

After all of the steps of the project have been completed for both the Old World monkeys and lemurs, the data would be converted into graphs and tables to easily see what is being compared, and the differences between the Haplorrhines vs. Strepsirrhines. My notes and observations would be converted into a research paper, with the data graphs and charts included. Relevant photos would also be included. 

Relevance: 

I have found no literature on the cognitive abilities such as memory in Red-tailed monkeys (Cercopithecus Ascanius) and no studies comparing their abilities with lemurs of any kind. Therefore, this study would be novel in that regard. There has also been a movement in the world of primatology and animal behavior, to get more accurate results by putting no stress on the animals, observing them in their habitat and comfort zone with their social/family group present, and presenting them with problems/stimuli congruent with their physical abilities and natural inclination (de Waal, 2017) (Croninl et al., 2017). This is how I would be conducting my research. Studies such as these also help in the conservation efforts of these incredible animals by fostering appreciation and understanding of their minds. This research could also lead to new enrichment practices for the animals. 

Works to be Cited: 

Bektic, Lejla. Habitat Preference and Foraging Behaviour in Adult Red-Tailed Monkeys (Cercopithecus Ascanius), SLU, Dept. of Animal Environment and Health, 30 June 2009, stud.epsilon.slu.se/337/. 

Cronin1, Katherine A., et al. “Studying Primate Cognition in a Social Setting to Improve Validity and Welfare: a Literature Review Highlighting Successful Approaches.” PeerJ, PeerJ Inc., 3 Aug. 2017, peerj.com/articles/3649/. 

de Waal, Frans. Are We Smart Enough to Know How Smart Animals Are? W.W. Norton & Company, 2017. 

Fichtel1, Claudia, et al. “The Lemur Baseline: How Lemurs Compare to Monkeys and Apes in the Primate Cognition Test Battery.” PeerJ, PeerJ Inc., 24 Sept. 2020, peerj.com/articles/10025/. 

Kittler, Klara, et al. “Cognition in Ring-Tailed Lemurs.” Folia Primatologica, vol. 86, no. 1-2, 2015, pp. 106–116., doi:10.1159/000368669 

And of course, here is the link to my video presentation of my project!

https://www.youtube.com/watch?v=2elLvPhhgpU