Coral
reefs are among the most fragile, heavily impacted, and
rapidly disappearing ecosystems on Earth. It is during
reproduction and larval development that the corals are
most vulnerable. The young, defenseless coral larvae in
the plankton are most sensitive to pollution and
predation. Yet these stages offer the greatest potential
for developing safe and relatively inexpensive new methods
of biological control.
In
a study by NURP's Caribbean Marine Research Center,
molecular biologists Daniel and Aileen Morse of the
University of California at Santa Barbara discovered the
signal molecules that cue coral larvae to settle and
metamorphose on specially favorable habitats where the
corals can grow well. The researchers are now working to
incorporate these natural signal molecules into artificial
surfaces that act like a kind of "larval
flypaper," inducing the larvae to settle and
metamorphose on these recruiting surfaces. This technology
could be developed to provide a low-cost and reliable
means for production, reseeding, and restoration of
corals. The results of their work should make production
of coral by aquaculture a feasible alternative, thereby
reducing harvesting pressure on natural stocks. The Morses'
discovery of the signal molecules that control the
settlement of abalone and other shellfish larvae have led
to innovative new technologies for low-cost aquaculture
and reseeding programs, forming the basis of commercially
successful new aquaculture industries in the United States
and other countries.
This
research also has the potential for important medical
applications since the molecules that control coral
recruitment might have an analogue to human signal
molecules that regulate development of human cells. Daniel
Morse became interested in the evolution of marine
signaling systems while he was a professor at Harvard
Medical School. The chemical sensing mechanism that cues
coral larvae to settle has evolved in mammals as well, but
for different purposes. By isolating coral signal
molecules, Morse might be able to identify the signal
molecules in the human body that activate the body's
immune system against disease or that regulate gene
expression.
