All of my research experiences in animal behavior have focused on understanding social behavior and animal cognition, especially decision-making and learning. I worked with several species of insects, birds, and mammals to address these topics. Below are some of my major research projects.
Mate location behavior of Gillette's checkerspot butterflies
Caching decisions of Florida scrub-jays
Learning and decision-making in bumblebees
Social networks and movement decisions in domestic sheep
Social networks and cognition in ring-tailed lemurs
Transmission of information through corvid social networks
I obtained my undergraduate degree from Stanford University, Biological Sciences Department, and was advised by Dr. Carol Boggs. We conducted our research at the Rocky Mountain Biological Lab, Gothic, Colorado. My field research involved working with butterflies, mostly Euphydryas gillettii (Gillette's checkerspot), a species native to Wyoming which had been experimentally introduced to Colorado in 1975. During my first summer at RMBL, we witnessed a population explosion that we outlined in our paper in the Journal of Animal Ecology in 2006 (click the journal cover on the left for the pdf).
For my honors thesis, I investigated the mate-location strategies of E. gillettii males. The males either perch on a high location (mostly the high branches of spruce trees) and wait for the females to fly by them, or they fly over the habitat and actively seek females. The ability to find mates has direct implications on how the population is sustained, and the results of my honors thesis research suggested that habitat factors, weather conditions, and presence of other males all correlate with which strategy dominates in the population at a given time. My undergraduate thesis was supported through Center for Conservation Biology and an HHMI sponsored grant from Undergraduate Research Opportunities at Stanford University.
I worked as a research intern for Dr. Reed Bowman at the Archbold Biological Station in Florida in 2005. During my time at Archbold, I completed an indepedent research project on the food storing (caching) behavior of Florida scrub-jays. Species ranging from rodents to birds will pilfer each others' caches, and multiple strategies exist to avoid pilferage. One strategy frequently used by caching animals is to avoid caching when others are present. Because of this avoidance behavior, caching behavior allows studying how foraging decisions can be significantly influenced by social behavior, and provides a window into multiple aspects of animal cognition including learning, memory (possibly including episodic-like memory, which involves remembering what, where and when), and decision-making.
Like other caching species, Florida scrub-jays frequently recover food items they have cached. I investigated whether the decision to eat or recache a recovered item is influenced by the social environment or by abiotic factors that influence the viability of the cached item. The scrub-jays' decision to eat or to recache was not influenced by the social environment because they were able to avoid potential social conflicts by flying away from the cache recovery site. However, their decisions were significantly influenced by habitat properties that influenced the viability of the caches. For example, they ate majority of the items that they had recovered from places with high moisture, which is known to degrade caches. We published our results in Ethology in 2011.
My master's thesis was based on investigating whether signals in multiple sensory modalities provide an advantage for learning and decision-making of the organisms that attend to those signals. Humans, for example, show a trade-off between the speed and the accuracy of decisions; most of the time, we have to slow down to make accurate decisions. This trade-off has been shown in multiple animals, one of which is bumblebees.
Together with my master's thesis advisor, Dr. Daniel R. Papaj at the Department of Ecology & Evolutionary Biology, University of Arizona, I looked at whether providing information to bees in multiple modalities leads to changes in the speed-accuracy trade-off to result in faster and/or more accurate decisions. We gave bees an artificial flower patch in which only some flowers provided nectar. When flowers differed in their shape and scent, bees were able to distinguish better between different flowers than when the flowers differed only in their shape. The speed-accuracy trade-off was present in all of their decisions. However, interestingly, bees' decisions were consistenly more accurate across a range of decision speeds when shapes were coupled with scents. We published our results in Proceedings of the Royal Society B: Biological Sciences in 2008.
Every year, Princeton EEB first year graduate students take the Tropical Ecology Field Course. In 2010, my cohort and I went to Kenya where one of my advisors, Daniel Rubenstein, has been conducting behavioral research on equids for many years. We stayed at the Mpala Research Center. Our course was lead by Daniel Rubenstein (Princeton), Iain Couzin (Princeton) and Tanya Berger-Wolf (University of Illinois at Chicago).
As a part of this course, several of us worked on tracking social interactions and group movement in domestic sheep. Every morning, we fitted the sheep in our study site with GPS units. By combining the GPS data and the daily observations, we constructed social networks based on social interactions and movement.
After my master's thesis, I took a short break from animal behavior to pursue my other academic interest: astrobiology. Astrobiology is the study of "the origin, evolution, distribution, and future of life in the universe" (astrobiology.nasa.gov). We, as biologists, study life and its diversity from unicellular organisms to vertebrates. At a bigger scale, however, all life we know represents a sample size of one. So, it would be incredible to find other life forms on other planets. Such a discovery would help us get closer to understanding biology and address our curiosity about the extent of life in the universe. Besides, astrobiology has something to attract the interest of everyone interested in any discipline of natural sciences, whether it is astronomy, cosmology, planetary sciences, geology, physics, chemistry, or biology.
Between 2007-2009, I had the great opportunity to work at the SETI Institute (Search for Extraterrestrial Intelligence) and NASA Ames Research Center in Mountain View, CA. Click on the journal cover to access the paper we published in 2009 based on one of the projects I participated in.
Here are a few good websites that always have something interesting on this fascinating topic.
My Ph.D. dissertation focused on understanding the links between social relationships and cognition. Many group-living species display high social selectivity in their social behavior by interacting with some, but not all, of conspecifics in their group. I worked with ring-tailed lemurs (Lemur catta) to address the mechanisms behind social selectivity and its consequences for cognition. Lemurs are endemic to Madagascar but can be studied in multiple research stations across United States. My field sites included two of these research stations: Duke Lemur Center in North Carolina and St. Catherines Island in Georgia. My dissertation was supported through grants and fellowships from Princeton University, American Society of Primatologists, American Society of Mammalogists, and Animal Behavior Society.
The ability to recognize individuals is critical for maintaining selectivity in social interactions. In collaboration with my Ph.D. advisors Dr. Asif Ghazanfar and Dr. Daniel Rubenstein, and with Dr. Christine Drea from Duke University), we tested whether ring-tailed lemurs use information from multiple sensory modalities to recognize group members. We demonstrated that lemurs recognize familiar females by matching females' vocalizations and scents and published our results in Proceedings of the Royal Society B: Biological Sciences in 2014.
Our paper titled "Individual recognition through olfactory - auditory matching in lemurs" was featured in Duke University, Natural History magazine (June 2014 issue), NSF, and Science et Vie Découvertes (May 2017 issue).
Another paper from my Ph.D. research demonstrated that vocal exchanges complement grooming interactions in lemurs. Lemurs are very vocal and frequently produce contact calls that elicit responses from group members. However, our research showed that lemurs are highly selective in their responses, and preferentially respond to the contact calls of the conspecifics with whom they share strong social bonds.
Our paper titled "Lemurs groom-at-a-distance through vocal networks" was featured in Science Editor's Choice, Princeton University, ScienceNews, Nature World News, Pacific Standard, Daily Mail, and Today's Science. The Altmetric score for our paper is currently ranked as #9 among all papers published in Animal Behaviour.
As part of my Ph.D. research, I worked with common ravens (Corvus corax) to investigate the role of social relationships in learning. In collaboration with Dr. Christine Schwab and Professor Thomas Bugnyar from the University of Vienna in Austria, and with Dr. Will Hoppitt from the University of Leeds in UK, we tested whether different social relationships play different roles in influencing how information is transmitted through social networks.
We constructed social networks based on affiliative interactions (such as preening), aggressive interactions, and close physical proximity. We then tracked how novel information (i.e. information on how to open a box to access a food reward) spread in the group, to analyze which network best predicted the pattern of information transmission. Ravens selectively observed and learned from the group members with whom they shared affiliative connections and strong social bonds.
Our paper "Social networks predict selective observation and information spread in ravens" was published in Royal Society Open Science. It was featured in University of Vienna news (German, English), derStandard, Neue Zürcher Zeitung, Wiener Zeitung, LeScienze, and Washington Post.