Note: IBRG welcomes presentations given by visitors of our affiliated labs. Guest presenters are indicated by an asterisk (*) in the schedule below.
|No meeting — panel discussion: Current topics in bee research|
|Chris Reid *|
|No meeting due to spring break|
|Mircea Davidescu (room change: Guyot 100)|
|Thomas Kariuki * (time change: 11am)|
|Gordon Berman, Colin Twomey and Haishan Wu (Special meeting: 2–4pm)|
Similar to other animals, Drosophila males use species-specific courtship songs to bias female mating decisions. The Murthy lab studies how these songs are produced and perceived by the nervous system. This talk will focus on behavioral experiments that reveal the neural computations that underlie song generation and patterning in males and song responses in females.Back to schedule
My PhD work focused on interplay between social personality variation in mosquitofish and their ecological impacts. In this talk I will present a model of shoaling and foraging dynamics which suggests that producer-scrounger type foraging dynamics emerge from shoaling rule variation, as well as an experiment suggesting that social personality variation within a group can enhance a group's foraging performance.Back to schedule
During my PhD I studied problem-solving in distributed natural systems such as ant colonies and slime moulds. This talk will focus on how the acellular slime mould Physarum polycephalum uses a spatial memory system to solve a classic test of autonomous navigational ability commonly used in robotics, as well as to sense and respond to heterospecifics in the environment.Back to schedule
In my larger study of social behavior of butterflies*, one species establishes “traplines.” The males repeatedly visit places where virgin females might appear; the females circulate while laying eggs. The traplines are partly organized by slavish response to a simple environmental cue, but there is evidence of individual “decisions.” Optimal traplines might be solutions to the “NP-hard traveling salesman problem.” A mildly sleazy argument suggests that adding more competing salesmen may simplify the calculations to the point where a butterfly can do them. In my usual IBRG talk, the data, OR the theory, OR their integration is highly speculative. In this case, it’s "AND" for all. So in the hope of your constructive criticism, I’ll present both the allures and the weaknesses of my data, my analysis, and my synthesis.
* See poster inside the door to Guyot 305.Back to schedule
The highly variable nutrient content of tropical rain forest soils can encourage novel adaptations for nutrient acquisition in plants, including adventitious root growth above the soil surface and the use of arthropod excreta for nutrient subsidies. Tree trunks and logs can act as nutrient sinks that attract roots, provided such nutrients are accessible. Termites can facilitate access to nutrients stored in logs and trees through the digging of tunnels and by enriching substrates through nitrogen-fixing gut bacteria. Here we show how roots are significantly more likely to occur above the soil surface on substrates colonized by termites, supporting the hypothesis that termites accelerate nutrient cycling in tropical rain forest by making nutrients more accessible or attractive to plant roots.
* Joint work with Mingzhen Lu and Joshua Daskin.Back to schedule
The vertebrate hindbrain contains various sensory-motor networks controlling movements of the eyes, jaw, head, and body. A novel patterning is present in larval zebrafish where stripes of neurons with shared neurotransmitter phenotype extend throughout the hindbrain and reflect a broad underlying structural and functional patterning. I will discuss experiments using confocal imaging of activity of neurons during swimming, as well as molecular and electrophysiological techniques to give a specific example for how a network is organized within this stripe architecture. This simple organization probably forms a foundation for the construction of the networks underlying the many behaviors produced by the hindbrain.Back to schedule
For animals that forage or live in groups, finding the perfect position within the group can be crucial. Individuals near the front of a group may have improved access to food but also be exposed to greater predation risk. Animals may therefore attempt to modulate their position within a group based on their current energetic needs. I will present some preliminary experimental data that show how hunger level and environmental information interact to determine leadership in schools of Golden shiners foraging in a Y-maze. Hungry fish tend to rush to the front of the group initially but, as the group nears the decision point, informed individuals take the lead. We can all speculate together on what this means.Back to schedule
We will have a special Integrative Behavior Group Meeting to discuss some recent developments in quantitative behavioral analysis in the lab and the field. We will demonstrate some state of the art technologies for imaging, quantifying and analyzing behavior in invertebrates and vertebrates with short presentations by Gordon Berman (Physics and Lewis Sigler Institute), Colin Twomey and Haishan Wu (EEB). This will be followed by a discussion regarding the future of behavioral research and how these techniques may be applied more broadly both within, and outside, Princeton.Back to schedule
The period immediately following parturition is a time of heightened predation risk for ungulate neonates. I will discuss a hypothetical framework of the factors contributing to neonate predation in ungulates and draw on ten observations of perinatal behavior in Thomson’s gazelles in Kenya to assess the validity of the framework for this species. In particular, I will examine the effect of two maternal strategies: isolation for parturition and birth site selection. I am currently finishing analyses and writing this study up for my dissertation, so I appreciate constructive feedback!Back to schedule
For group living animals, social context represents a large part of their external environment. As it is readily acknowledged that an animal's environment influences its behavior, my thesis work was based on determining the personality of individual zebrafish, and then comparing their behavior across social contextsto determine the effects of different social environments on behavior. When in a pair, an individual's change in behavior was predicted by their asocial personality, the personality of their partner, and whether they were the shyer or bolder member of the pair. Preliminary data and analysis on groups of 8 fish indicate that average group personality and diversity of personality influence group cohesion during a decision making task. There's reams of data here just beginning to be analyzed, so any and all comments and critiques are welcome!Back to schedule
For over a century, researchers have been investigating collective cognition, in which a group of individuals together process information and act as a single cognitive unit. However, we still know little about circumstances under which groups achieve better (or worse) decisions than individuals. Our research directly addressed this longstanding question, using the house-hunting ant Temnothorax rugatulus as a model system. Here we applied concepts and methods developed in psychology not only to individuals but also to colonies in order to investigate differences of their cognitive abilities. This approach is inspired by the superorganism concept, which sees a tightly integrated insect society as the analog of a single organism. We combined experimental manipulations and models to elucidate the emergent processes of collective cognition. Our studies show that groups can achieve superior cognition by sharing the burden of option assessment among members and by integrating information from members using positive feedback. However, the same positive feedback can lock the group into a suboptimal choice in certain circumstances. Although ants are obligately social, our results show that they can be isolated and individually tested on cognitive tasks. We hope that this novel approach will help the field of animal behavior move towards better understanding of collective cognition.Back to schedule