Corals are under severe threat from climate change as higher temperatures cause them to lose the algae that provide them with energy. But salvation may come in the form of a newly discovered ability of corals to swap their algal partners with strains that can take the heat.
Among all of the world’s animals, the two which have built the largest settlements could not be more different.
Among all of the world’s animals, the two which have built the largest settlements could not be more different.
The champions, humans, are intelligent and mobile, rapidly adapting to new conditions with technology and ever-changing strategies. In contrast, the runners-up, corals, seem unchanging and immobile, spending their lives ensconced in their impressive but stationary reefs.But it now seems that corals may have to adapt quickly in the face of looming extinction, ironically, brought about by humans.
Corals are hugely successful animals. Their reefs have endured across millions of years and today, they cover an area of 280,000 square kilometres, larger than the entire United Kingdom.Their success depends on a partnership with a group of algae called zooxanthellae.
Over a million of these lodgers can live in a single cubic centimetre of coral, and they provide their landlords with both colour and energy through photosynthesis.
Despite their benefits, the algae are expensive to maintain. During periods of environmental stress, the corals eject them to make ends meet, losing their colour in the process. These ‘bleached’ corals (below) are free to regain their partners at easier times, but if conditions don’t improve, they die.
Despite their benefits, the algae are expensive to maintain. During periods of environmental stress, the corals eject them to make ends meet, losing their colour in the process. These ‘bleached’ corals (below) are free to regain their partners at easier times, but if conditions don’t improve, they die.
