Dr. Richard B. Aronson
Senior Marine Scientist, Dauphin Island Sea Lab
Associate Professor, Department of Marine Sciences
University of South Alabama
Ph.D., 1985, Harvard University

Research Description:
I am interested in why marine bottom communities change on different scales of space and time. My research program has two principal foci: the paleoecology of echinoderm populations and the communities to which they belonged, and coral reef ecology. Although these two topics would appear to be unrelated, both are providing clues to the determinants of community structure and community dynamics.

Dense populations of echinoderms, including stalked crinoids and brittlestars, were common constituents of shallow-water communities during the Paleozoic and early Mesozoic Eras. These 'crinoid gardens' and 'brittlestar beds' carpeted the floors of shallow seas, filtering organic particles from the water.

Yet today, stalked crinoids occur only in the deep-sea, and brittlestar beds are rare in shallow water. Both types of populations declined precipitously in shallow water beginning in the Jurassic Period. Their decline was related to the contemporaneous diversification of fish and crustaceans adapted to prey on hard-shelled invertebrates.

On an evolutionary scale, then, predation has had an important role in determining the structure of modern marine communities. On ecological scales--decades to centuries down to hours to days--predation is again important in determining where brittlestar beds will and will not be found.

I am now concentrating on the ecological and evolutionary implications of predation on crinoid and ophiuroid populations that lived in Antarctica during the Eocene (40 million years ago).

Over the past two decades, Caribbean coral reefs have been undergoing an alarming change. To an increasing extent, they are being taken over by macroalgae (seaweeds).

My research efforts in the Florida Keys, Jamaica, Belize and the U.S. Virgin Islands are directed toward understanding the relationships among disturbance, herbivory, coral abundance and coral diversity.

Again, I am interested in whether these relationships are similar on multiple scales: among landscapes within reefs, among reefs within localized areas and among areas throughout the region.

Representative Publications:
Aronson, R. B. 1992. Biology of a scale-independent predator-prey interaction. Mar. Ecol. Prog. Ser. 89:1-13.

Aronson, R. B. 1993. The effect of Hurricanes Gilbert and Hugo on Caribbean back reef echinoderm assemblages. Coral Reefs 12:139-142.

Aronson, R. B. 1994. Scale-independent biological processes in the marine environment. Oceanogr. Mar. Biol. Ann. Rev. 32:435-460.

Aronson, R.B. and W.F. Precht. 1995. Landscape patterns of reef coral diversity: a test of the intermediate disturbance hypothesis. J. Exp. Mar. Biol. Ecol. 192:1-14.

Aronson, R.B. and K.L. Heck, Jr. 1995. Tethering experiments and hypothosis testing in ecology. Marine Ecology Progress Series 121:307-309.