The deep-sea photographer who captured a 'living fossil'

As scientists race to find deep-sea species before they disappear, photographers help with a taste of danger.

In 2010 four friends, carrying 32kg (71lb) worth of camera equipment, sank beneath the waves in Sodwana Bay on the east coast of South Africa. That's when photographer Laurent Ballesta looked directly into the eye of a creature that was thought to have died alongside the dinosaur - making him the first diver to photograph a living coelacanth.

"It's not just a fish that we thought went extinct," Ballesta said. "It's a masterpiece in evolutionary history."

Go back to the beginning of the age of the dinosaurs, and you'll find coelacanths on every continent, living in the evaporating swamps of the Triassic period. 410 million years ago, coelacanths belong to a group of "lobe-finned" fish that left the oceans about 390 to 360 million years ago. Its strong, fleshy fins were a precursor to the paired limbs of tetrapods, which include all land-living vertebrates – amphibians, reptiles, birds and mammals, and yes, humans too. In fact, coelacanths are more closely related to tetrapods than to other known fish species.

The least known fossil coelacanth is 66 million years old, suggesting a long extinction of these animals. Then, in 1938, a fish with blue-green scales and four limb-like fins was caught in a trawl net off the coast of South Africa. Further investigations began and, in 1987, anthropologist Hans Frick led an underwater expedition off the coast of Grande Comore, where he was able to capture a live coelacanth on film for the first time.

These coelacanths are called living fossils, although experts say this nickname is incorrect and that coelacanths did indeed evolve, albeit very slowly. For one thing, this elusive fish no longer resides on the periphery of land, but deep in the ocean.

"Every time they were caught, it was too deep, too deep for normal scuba diving techniques at the time," Ballesta said. "So, it was a fantasy in my mind." But, in 2000, Ballesta heard about a diver named Peter Timm. "During a deep dive, Tim found a coelacanth in a cave only 120 meters (393 feet) [deep]." So, in 2010, after intensive deep-dive training, and with the help of newly available rebreather diving technology—which allowed him to stay underwater longer than previously possible—Balesta enlisted Tim as his guide.

Coelacanths live in the benthic zone—the ocean floor—along steep underwater slopes and shelves up to 300 meters (984 feet) deep. During the day, they congregate in submarine caves, emerging only at night to feed. It was in such a cave that Ballesta met his first coelacanth.