Life Sciences Commons^™

Renal Function In Suckling And Fasting Pups Of The Northern Elephant Seal, Dorian S. Houser, Daniel E E. Crocker, Paul M. Webb, Daniel P. Costa

Arts & Sciences Faculty Publications

Elephant seals fast for prolonged periods without access to water. This is made possible, in part, by reductions in urine production. However, the mechanisms involved in reducing urine production are not understood. In this study, glomerular filtration rate (GFR) was measured in five northern elephant seal pups (Mirounga angustirostris) via the inulin clearance technique. Measurements were made during day 9 and day 18–22 of nursing and the second and eighth week of the postweaning fast. Plasma aldosterone and cortisol concentrations, quantified by radioimmunoassay, were measured in eight other weanlings during the second and eighth week of the fast. …

Taphonomic Evidence For Late Pleistocene Transitions In Coral Reef Community Composition, San Salvador, Bahamas, Thomas A. Rothfus, Benjamin J. Greenstein

Arts & Sciences Faculty Publications

Over the past 20 years, the composi­ tion of Caribbean coral reef communities has changed drastically. The ecology of modern reefs, however, has only been studied since the late 1950's. Thus, only a thirty year data set on changes in coral community composi­ tion exists with which to assess the current faunal transition. The need for longer term data has been recognized by marine ecologists as essential for determining whether the cur­ rent transition is part of a long tenn cycle or itself is an unprecedented phenomenon.

On Telephone Pole Reef, San Salva­ dor, Bahamas, a transition from Acropora cer­ …

Nitric Oxide And Cnidarian-Dinoflagellate Symbioses: Pieces Of A Puzzle, Henry G. Trapido-Rosenthal, Katherine H. Sharp

Arts & Sciences Faculty Publications

The presence of nitric oxide synthase (NOS) activity is demonstrated in the tropical marine cnidarian Aiptasia pallida and in its symbiotic dinoflagellate algae, Symbiodinium bermudense. Enzyme activity was assayed by measuring the conversion of arginine to citrulline. Biochemical characterization of NOS from Aiptasia was characterized with respect to cellular localization, substrate and cofactor requirements, inhibitors, and kinetics. In response to acute temperature shock, anemones retracted their tentacles. Animals subjected to such stress had lower NOS activities than did controls. Treatment with NOS inhibitors caused tentacular retraction, while treatment with the NOS substrate L-arginine inhibited this response to stress, as did …

Resilience And Recovery Of Coral Reefs From Large-Scale Disturbances: Contrasting Patterns For San Salvador Island, Bahamas, And Belize, Paulette Peckol, Benjamin J. Greenstein

Arts & Sciences Faculty Publications

Coral cover and diversity are declining while macroalgal abundance is increasing in most Caribbean coral reef systems. Although a complex interaction of natural and anthropogenic disturbances is likely causal, the effects of a specific disturbance may vary dramatically for different reef systems. The coral reefs off the coasts of San Salvador Island, Bahamas and Belize, considered to be in relatively good condition, recently experienced near-direct hits by Hurricanes Floyd (1999) and Mitch (1998), respectively. In addition, NOAA scientists indicated that during 1998, tropical sea surface temperatures (SSTs) reached their highest levels above the normal annual maximum for this past century. …