Heat tolerance in corals can be passed down the generations, suggesting that corals can adapt as the climate warms.

Credit: M. Matz

Researchers have suggested that corals physiologically acclimatize to higher temperatures rather than inherit heat tolerance. To test this idea, Line Bay at the Australian Institute of Marine Science in Townsville, Australia, Mikhail Matz at the University of Texas at Austin and their team bred corals (Acropora millepora; pictured) from two locations in Australia separated by 5° of latitude. Offspring produced by parents from the warmer area had an up to 10 times greater chance of survival when exposed to heat, compared with the larvae of parents from the cooler region. Larvae generated by crossing corals from the warm area with those from the cool region inherited key genetic differences associated with heat tolerance.

Corals that thrive in the heat could be moved to other latitudes so that they reproduce with local corals and introduce heat tolerant adaptations to the population.

Science 348, 1460–1462 (2015)