All toxicant exposures were for 4 hours at the concentrations indicated. The darkness of the slot blot is directly proportional to the amount of probe binding. Densitometry was performed on all the slot blots, providing quantitative measures of the amount of up-regulation in gene expression. Figure 2 . Temperature responsiveness of the coral gene detected by the long dibrom probe.
Controls are samples exposed to ambient temperatures in the lab or on the collecting boat.
Comparison of field samples collected of A. cervicornis from the Florida Keys over 3 years indicates a temporal pattern of stress induced gene expression. No stress gene expression in this sample was detected by the long dibrom probe. In contrast, samples collected on this date and exposed to dibrom in the lab demonstrated stress gene induction. Temperature stress was an obvious candidate because this probe is known to be responsive to temperature. The gene expression detected by this probe also is induced by dibrom and naphthalene exposure, so perhaps these populations of A. cervicornis were exposed to organophosphate pesticides or polycyclic aromatic hydrocarbons.