This shortarticle was initially included on Hakai Magazine, an online publication about science and society in seaside communities. Read more stories like this at hakaimagazine.com.
Arah Narida leans over a microscopiclense to look into a plastic petri meal including a hood coral. The animal—a pebbled blue-white disk approximately half the size of a pencil eraser—is a marvel. Just 3 weeks ago, the coral was smallersized than a grain of rice. It was likewise frozen strong. That is, upuntil Narida, a graduate trainee at National Sun Yat-sen University in Taiwan, defrosted it with the zap of a laser. Now, simply underneath the coral’s arms, she spies a small divot in the skeleton where a 2nd coral is start to bud. That little cavity is proof that her hood coral is reaching theadultyears, a task no other researcher has ever handled with a formerly frozen larva. Narida smiles and snaps a image.
“It’s like if you see Captain America buried in snow and, after so lotsof years, he’s alive,” she states. “It’s so cool!”
For almost 20 years, researchers haveactually been cryopreserving corals—freezing them at temperaturelevels as low as -196 °C for long-lasting storage. The objective hasactually been to one day plant corals grown from cryopreserved samples on reefs pestered by bleaching and acidification. Yet, development hasactually been agonizingly slow. When Narida and her associates published a researchstudy earlier this year detailing how they effectively grew adult corals from cryopreserved larvae, it was a turningpoint for the field.
Coral cryopreservation is challenging in part since freezing and defrosting wreak havoc on cells. As researchers lower the temperaturelevel, the water in the coral’s cells turns to ice, leaving them dehydrated and deflated. Reheating is simply as fragile: if the coral is warmed too gradually, melting ice can refreeze and tear through the cells’ external membranes. The outcome is a soaked mess, as the cells’ innards ooze out through jagged holes—picture a frozen strawberry endingupbeing limp and shriveled as it defrosts.
Through trial and mistake, though, cryobiologists have established the methods that assisted Narida grow her hood coral to adu