Arctic Brittlestars, a species of starfish common to polar waters, exhibit rings on their internal skeletons that can be used to infer rates of growth.

Polar waters have dramatic interannual and geographic variations in ice coverage, which may affect the availability of algae -- a source of food for brittlestars and other ocean-floor animals.

Dalby's research has shown that in polar waters brittlestars may be useful indicators in variations in the amount of food, but food supply to brittlestars may not vary with ice cover.

Dalby has researched brittlestar growth in relation to ice cover and food supply with William G. Ambrose, assistant professor of biology.

Dalby received a bachelor's degree in zoology from the University of Alberta in Canada, a master's degree in marine ecology from Florida State University and a doctoral degree in marine ecology from the University of Melbourne in Australia.