Life in the abyss, more than “primordial monsters”

rana pescatrice degli abissi

The Melanocetus or “black devil”, one of the most famous fish of the abyss.
Credits: BBC

There was a reason if before 1872, when the Challenger Expedition was over, it was thought that the oceanic abyss was inhabited. How can a living being survive without solar energy and light and with an unbearable pressure? Then the British oceanographic study brought to light thousand of undiscovered species and that started a slow yet inexorable progress in scientific research, adding more and more pieces to the puzzle. A lot is still unknown though, there is more knowledge about the moon, for example.

Just with their surface, oceans cover 2/3 of planet Earth, so they are easily the widest habitat. And now we are understanding how relevant biodiversity is, even 200 metres below the surface, where the sun can’t set. More or less, the same biodiversity as the rain forest, considered synonym of richness of life.

About ten years ago, biologists found more than 12 thousand species living in arctic and antarctic seas and 235 species lived both in the North and South Pole, meaning that warm waters didn’t interrupt massive migrations. And the list is constantly updating, thanks to scientific and technological progress. For example, the National Oceanography Centre of Southampton used a remote control vehicle, which goes under the quite scary name of Isis, able to enlighten the oceanic depth. And even if that’s amazing, we are still talking about a small portion out of an exterminated environment.

Isis centro oceaonografico southampton

The remote control vehicle used to enlighten the oceanic depths, named Isis. Credits: National Oceanography Center

The abysses present different landscapes, just like the landmass: from flat plains that cover half of the Earth to mountain chains like the Atlantic Rift, longer than the Andes, the Rocky Mountains and the Himalaya altogether; from tight canyons to isolated mountains like those spread through the Pacific Ocean.

If seabeds are mostly arid, on the rocks, even the antarctic ones, corals and sponges can proliferate. Surely not the classic environment in which we would imagine to see coral reefs. Nevertheless, the abyssal species of the genus Lophelia cover wider surfaces than tropical ones. Unfortunately, both habitats are endangered, whether it’s the climate change or trawling, detrimental even at great depths.

The abyss isn’t only populated by “monsters”, weird (for our standards) creatures that are definitely capturing the collective imaginary. Phytoplankton is at the basis of everything. It can be found anywhere, even among antarctic currents, then, when warmer and colder water masses encounter, it rises up to the surface, where it finally reaches the light and can prosper, starting the food chain.

corallo abissi

Abysall corals, even more widespread than tropical ones.
Credits: National Oceanic and Atmospheric Administration

In addition, phytoplankton draws nourishment from fertilizers like dolphin’s waste and carcasses – better yet of large size like the cachalote ones.

Despite the richness of crustaceans, molluscs, sponges, corals and phytoplankton, bizarre, apparently primordial creatures take the scene. They are anything but basic though, actually they are the result of an extraordinary evolution, based on functionality more than embellishment – it would be useless in total darkness.

Well, not total darkness, as many species became bioluminescent – able to emit light – or adapted to the external pressure, 1000 times higher than on the mainland. That’s why many species of the abyss are big just a few centimeters, move slowly to save energy in conditions of food shortage or, for the same reason, can resist without eating even for a year, like some sharks do.

According to a study published on Science, the exceptional evolution of the opsins, proteins in the cornea responsible for the light waves absorption, lead the abyss species to at least 24 mutations.

Advanced technologies made this habitat, once thought inhospitable, a little less mysterious and that had an indirect effect. Researchers in many fields tried to “copy” some features of these species to improve technologies, in a virtuous cycle.

squalo capopiatto

A sixgill shark, they can resist without eating for a year

For instance, the wave motion of the oceans floor fishes inspired membranes that can replace propeller blades, dangerous for the inhabitants of the sea; some companies started to produce lamps that don’t need electricity, as they are rich of bioluminescent bacteria; medical studies are observing bacteria able to metabolize heavy metals, making them non toxic, soluble and therefore removable from groundwater and the food chain.

Paraphrasing Shakespeare, we could say that “there are more things in the abyss, Horatio, then are dreamt in your philosophy”.


0,90 cent in Italy is the average price for the famous Espresso. Coffee brings energy and you readers too 🙂 Grazie! ❤ P.S. There will be plenty of rewards for the best donors!


Leave a Reply