Senior Sarah Dean won highest honors (first place) in her division (Biology and Environmental Science) at the 27th annual Upstate New York Junior Science and Humanities Symposium (JSHS) for her scientific studies into the predatory nature and activities of dragonflies. She will participate at a national symposium in Maryland in May.

The upstate New York event was held at the University at Albany on March 19 .

The following day, she presented her work again in the finals against other division winners and took second place overall, earning her a trip to to compete again at the national symposium. She will be one of only 240 students across the nation to attend the 50th National Junior Science & Humanities Symposium, May 2-6, in Bethesda, Maryland.

Details of her research are below.

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Title: Dragonfly Neural Response to Approaching Objects

Student: Sarah Dean

School: Scotia-Glenville High School

Teacher: Mr. Chris Judd

Mentor: Dr. Robert Olberg, Union College

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Here is the abstract for Sarah's research:

Dragonflies are deft visual predators. They capture their prey while in flight, extending their legs towards it at precisely the right time. This behavior requires a nervous system well tuned to depth perception.

Physical stimuli with realistic prey sizes and speeds were presented to dragonflies. Their neural responses were recorded extracellularly from their ventral nerve cord.

Analyses showed that the dragonflies did not respond to small, prey-sized stimuli until after the time of contact. This suggests that these neurons do not control the leg extension behavior.

There was also a trend of earlier response times for objects whose approach was angularly equivalent, but physically different. This observation suggests there is a method of depth perception other than detection of angular expansion.

Experiments in which the dragonfly was rotated show that responses came significantly earlier when the dragonfly was only rotated 15 degrees than when it was rotated 30 degrees or 45 degrees when recording from the ipsilateral side of the nerve cord.

The results support the idea that depth perception in dragonflies involves binocular vision.

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In January, Sarah and senior Corey McKenna took first place honors in the Eastern Regional Junior Science and Humanities Symposium (JSHS). They are pictured at left with their teacher, Chris Judd.

The two students presented their science research projects and answered difficult questions about their research. JSHS is a national program that promotes original research in the sciences, engineering and math at the high school level. It is sponsored locally by the University at Albany.