Genomic analysis explains how corals survive environmental catastrophe

STATE COLLEGE, Pa., Nov. 17 (UPI) -- New genomic analysis has offered scientists insights into how coral populations survive and expand in the wake of environmental disaster.

Researchers with Penn State University sequenced the genomes of three modern coral species from the genus Orbicella. The analysis allowed scientists to reconstruct the history of the three species.

O. annularis, O. faveolata and O. franksi are the only Orbicella species surviving today. Between 3.5 million and 2.5 million years ago, Orbicella reached its apex. But 2 million years ago, a massive extinction event wiped out the majority of Orbicella species.

Thanks to the latest analysis, detailed in the journal Current Biology, scientists are beginning to understand how the three species repopulated the Caribbean -- reclaiming territory vacated by their disappearing relatives.

"The wealth of genomic data allowed us to formally test hypotheses of coral population size changes, recapitulating observations from the fossil and environmental record," Michael DeGiorgio, assistant professor of biology at Penn State, said in a news release. "Our study is a textbook example of the power and the necessity of multidisciplinary teams of conservation, evolutionary, and computational biologists coming together to address important biological questions that would have been otherwise difficult to tackle."

Although scientists aren't yet sure exactly which genetic adaptations allowed the three species to survive, it's clear the corals had the ability to quickly populate ecological niches abandoned by more vulnerable species.

As climate change continues to threaten coral health across the globe, it has become imperative to understand how coral adapt and respond to environmental pressures.

"Corals are extremely ecologically and economically important, so understanding how their populations responded to environmental change historically is crucial for current conservation efforts," added Monica Medina, associate professor of biology at Penn State. "Our study of living corals confirms fossil evidence that suggested that coral populations can recover after environmental disasters and further suggests that current reef deterioration can be reversed if environmental stresses can be reduced."