Blizzards of the Deep — Part 1

"Which would we rather — more electric cars or more octopuses? What do we do when reversing climate change conflicts with preserving biodiversity?"


Blizzards of the Deep — Part 1


Ever since 1932, when biologist William Beebe and engineer Otis Barton squeezed through the 14-inch (36-cm) opening in their hollow metal ball they called a bathysphere, humans have been exploring the depths of the ocean. Beebe and Barton reached 2,200 feet on that first descent and would take the ball to 3,000 feet two years later. They saw flashlight fish, with bean-shaped pouches below their eyes filled with bioluminescent bacteria that blinked on and off as the fish winked. They saw sea jellies that made light by reacting a chemical called luciferin with oxygen. Other fish had eyes shaped like tubes to allow them to take in more light, or, like the giant squid, eyes the size of soccer balls. In 1960, Jacques Piccard and Don Walsh, in their research vessel Trieste, set a record that can never be broken by touching down on the lowest point on the surface of the Earth, 35,814 feet (10,916 meters) below sea level, in the Mariana Trench. 

 While the early explorers could take photographs through a porthole or describe what they saw, today’s research vessels have robot arms, sensors, and video cameras to gather samples and show what they’ve seen to the world. We have discovered countless organisms — like vampire squid, named for the webbing between tentacles that resemble a red bat wing, and a female octopus that sits on its nest of eggs for four and a half years, as its babies get large enough to enter their dark world.

Sunlight filters through the uppermost layers of water, but from 650 to 3280 feet (1000 meters), depending on where you are, it dims into what oceanographers call the Twilight Zone. Below that is the Midnight Zone, with no sunlight, temperature close to freezing, and enough pressure to crush a golf ball. For every 33 feet (10 meters) you descend, the pressure increases by 14.7 pounds per square inch. Animals like sperm whales and sea lions have flexible skeletons that collapse to accommodate these pressures when they dive.

With bodies or shells that maintain the same pressure inside as out, shellfish have their own bathyspheres. Invertebrates — animals that have no skeletons — reign on the ocean’s floor. There are deep sea versions of starfish, sea urchins, sea cucumbers, sea anemones, and even corals that do not require warmth or sunlight. Mud-dwelling ratfish have skeletons made of cartilage and can find worms and clams by sensing electrical fields. This might explain why sharks and rays were able to survive so many extinction events, because their special abilities — to contract, sense electrical fields, and smell at great distance — allow them to dive deep and find food when all of the usual sources have disappeared. Another strategy is that of the giant isopods that can slow their heart rate and go for years without eating.

Aliens of the Ocean

The octopus is a most unusual deep dweller. Its large brain and sophisticated nervous system, camera-like eyes, flexible body that can squeeze through very small openings, and ability to instantaneously switch color and shape are just a few of the striking features that appeared suddenly on the evolutionary scene and are not found together in any other creature. We know that octopusses (not octupi) come from the same biological line as nautilus, cuttlefish and squid, but they are so genetically different that it has opened some interesting questions about their origins. In June 2016, a number of web sites reported that researchers had examined octopus DNA and discovered it was either “alien” or “from space.” This was a bit overstated. The source, an article in the journal Nature, actually said that octopuses have a genome that yields an unprecedented level of complexity, composed of 33,000 protein-coding genes. This number is well beyond the number that can be found in a human being, so one scientist humorously compared it to an alien, which started the rumor.

Other scientists didn’t think it it is a joke. The March 2018 issue of the journal Progress in Biophysics and Molecular Biology (“Cause of Cambrian Explosion — Terrestrial or Cosmic?”) examined whether some of our evolutionary ancestors could have been extraterrestrial. The paper said that since the genes of the octopus “are not easily to be found in any pre-existing life form — it is plausible then to suggest they seem to be borrowed from a far distant ‘future’ in terms of terrestrial evolution, or more realistically, from the cosmos at large.” The paper proposed that we not so quickly discount the notion that octopus genes might have been extraterrestrial. The scientists concluded:
Thus the possibility that cryopreserved squid and/or octopus eggs, arrived in icy bolides several hundred million years ago should not be discounted, as that would be a parsimonious cosmic explanation for the octopus’ sudden emergence on Earth ca. 270 million years ago. 

Snow

What we have come to call marine snow is actually tiny bits of dead plants and animals, feces and plastic that fall like snowflakes from the surface and upper layers of the ocean. Some animals, like jellyfish, vampire squid, and sea urchins rely on this snow for food. Others rely on whalefalls, which is literally what it sounds like. When a whale or other large fish or mammal dies near the surface, its carcass drifts to the bottom where it becomes food for thousands of bottom dwellers, sometimes for many years. If there are more deaths of marine animals now from climate change, poisons, oil spills, radioactivity and other human-caused disasters, it stands to reason these are banquet years at the bottom of the sea. But then what?

Barring massive geoengineering interventions like OMTEC farms (Ocean Mechanical Thermal Energy Conversion), heat from the surface will not reach the depths of the deeper ocean during my lifetime, or for many lifetimes afterwards. You can think of the temperatures there as a kind of planetary memory because the average heat at different strata reflects previous ice ages going back hundreds of thousands of years. What changes, however, is the snow.


In the second part of this two-part series, we will look at those changes to the snow being caused by red tides, bottom trawls, seabed mining, carbon capture and storage, and microplastics. Readers willing to spend a dollar for a good cause can donate to my page on Patreon and get the second part now, but otherwise the second installment will be out with my free blog that comes out every Sunday.

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