Fall 2008 Seminars

Fall 2008 Asa Gray Seminars

October 6th, 2008

Title: TBA

Paul Kent
Associate Professor of Neurology
SUNY Upstate Medical University

Abstract: TBA

 

 

 

October 27th, 2008

"The role of prediction in prey interception by dragonflies"

Andrea Worthington
Professor of Biology
Department of Biology, Siena College.

Abstract: In an act of elegant precision, a dragonfly swoops up to pluck a flying insect from the air. The entire event, from takeoff to capture, often takes only one or two tenths of a second. It’s over so quickly that the flying insect usually takes no evasive maneuvers. By the time we humans can register that we saw something happen, it’s over. How does the dragonfly recognize its prey? How does it so quickly send the necessary information from eyes to brain to wings to guide the behavior? How does it so accurately plot its deadly course? These questions and more have occupied our interest for much of our professional lives as we have sought to understand the neural basis of this deadly accurate behavior. Our attempts to answer these questions has led us from inserting tiny electrodes into the dragonfly brain, to videotaping the natural behavior in the field, and finally to dissecting the behavior in a flight cage with high speed video.

 

November 10, 2008

"The Behavioral and Evolutionary Responses of Native Tadpoles to Introduced Predators"

Martin Schlaepfer
Assistant Professor of Environmental and Forest Biology
SUNY-ESF, Syracuse

Abstract: Tadpoles can generally increase their probability of survival in the presence of known predators by reducing their foraging activities or modifying their tail shape to increase swimming speed or lure attacks away from the head. It is unknown, however, to what extent tadpoles can induce such behavioral and morphological plasticity in response to
evolutionarily unfamiliar predators. Lowland Leopard Frogs (Rana yavapaiensis) are native to Arizona and are currently declining due to various introduced predators. Here I present results from mesocosm experiments in which I test whether tadpoles have evolved in response to the novel selective pressures of non-native predators.  mschlaepfer@esf.edu

 

November 24th, 2008

"Position Preferences within Swarms and Flocks"

Dr. W. L. Romey

 

Associate Professor of Biology

 

SUNY Potsdam

Abstract: Large groups of birds, fish, or insects appear to be randomly mixed. But how might individual differences in gender, hunger, size, and defenses influence position preferences? And, do animals respond to only one of these state variables at a time? For example, it has been found that hungry fish go to the outside of schools where the edge represents a trade-off between feeding opportunity and predation risk. Dr. Romey presents evidence from controlled experiments with whirligig beetles and simulation models showing that animals appear to take a variety of these factors into account when choosing positions within a group. Males tend to go to the outside in many species because of increased food needs. However, if they are bucking a current, they position themselves in the back where it is easier to swim. He also shows how simulation models suggest a proximate explanation for the above behaviors; a simple rule such as “defend a larger interpersonal space” can lead individuals to optimal positions. These experiments suggest some principles which may apply generally to flocks, schools, and other swarms. romeywl@potsdam.edu