Ocean warming is one of the most urgent threats to coral reefs (1–3). Some taxa may migrate in response to changing environmental conditions (4), but corals and other sessile organisms only migrate through larval movement (5). This is viable for coral species with planktonic larvae, but not for the many coral species with crawl-away larvae that cannot migrate far. Adult corals must therefore adapt evolutionarily or acclimate physiologically to survive warming. On page 895 of this issue, Palumbi et al. (6) show that tabletop corals (see the first photo) can both acclimate and adapt to elevated temperatures in American Samoan back-reef pools (see the second photo), where high-temperature extremes are common. If the result holds for other species and locations, it provides hope for coral reefs under global warming. |
