5 mysteries of the ocean that science still hasn't solved

1. Why do whales wash up on shore

All sorts of cetaceans periodically take and jump out of the usual water element on inhospitable harsh rocks or beaches, where death awaits them.

Whales and dolphins on the shore perishM. D. Blood. Beached Whales: A Personal Encounterusually from dehydration. Or when the body weight, not compensated by the surrounding aquatic environment, compresses the lungs. Some simply choke on the tide, during which water fills their blowhole.

Why it even occurs to cetaceans to settle accounts with life is a mystery.

Maybe do it them encourageM. D. Blood. Beached Whales: A Personal Encounter uncomfortable temperature conditions or geomagnetic disturbances. Or the sonar built into the whale brain is acting up.

Finally, there is assumptionsS. L. Chambers, R. N. James. Sonar termination as a cause of mass cetacean strandings in Geographe Bay, South‑Western Australia / Proceedings of ACOUSTICS 2005

that animals go crazy when they hear the sonars of ships passing by. Although whales were washed ashore even before people even invented shipbuilding.

So science has yet to find the answer to the question of how to save whales from suicide.

2. Who whistles at the bottom of the ocean

The US National Oceanic and Atmospheric Administration is constantly recording some strange sounds coming from the ocean floor. Most of them can be explained by natural causes. Let's say giant iceberg crawling along the bottom or a flock of whales coughed in unison. But sometimes there are quite anomalous phenomena.

For example, in the Pacific Ocean, near the equator, a sound recorded by hydrophones is periodically heard, which scientists calledUpsweep / PMEL Acoustics Monitoring Program Upsweep ("Rising"). It was first recorded in 1991 by oceanologists from the Marine Environment Research Laboratory in the Pacific. This phenomenon is seasonal, peaking in spring and autumn. What makes it is a mystery.

Another incomprehensible sound that is sometimes heard at the bottom of the sea is the so-called Whistle (“Whistling”). His first recordings appearedSubmarine Volcanic Eruption (Whistle) / PMEL Acoustics Monitoring Program in 1997. The source has not yet been found. Presumably, this is a sound of volcanic origin.

3. Why narwhal tusk

This charming creature in the photo is a narwhal. Belongs to cetaceans, loves fish and cephalopods for their taste and nutrition, swims in cold Arctic waters, tries not to mess with polar bears and killer whales. In short, the animal as a whole is ingenuous, if not for one thing.

On the head of a narwhal sticks out a huge tuskHow Narwhals Work / HowStuffWorks - This is the upper left tooth, which grows outward right through the gum and upper lip. Some unique ones even grow not one, but two such tusks. Mostly males are equipped with them, but sometimes females can boast of such decoration. The length of the tusk is from 1.5 to 3 m, weight - up to 10 kg.

One or two tusks are the only teeth of the narwhal, besides them the poor fellow has nothing. Therefore, you have to swallow food whole.

And scientists still will not understand, but why, in fact, neededR. C. best. The tusk of the narwhal (Monodon monoceros L.): Interpretation of its function (Mammalia: Cetacea) / Canadian Journal of Zoology this tooth. As a weapon, it is not that much useful, although it is quite durable and can even bend 30 centimeters in all directions without harm to itself. It is also not very convenient to break the ice with them - it is too thin. Yes, and observations that narwhals skillfully fenced with their tusks in battle, something has not been recorded.

One theory says that the tusk serves decorationR. C. best. The tusk of the narwhal (Monodon monoceros L.): Interpretation of its function (Mammalia: Cetacea) / Canadian Journal of Zoology for males, say, like the tail of peacocks or the antlers of deer. To be, then, than to shake in front of rivals during marriage competitionsBiology of the Narwhal (Monodon Monocerus) / NarwhalTusks.com. But this does not explain why females also have it.

Another option - the tusk serves as a kind of sensory organ, since it riddled withM. T. Nweeia, F. C. Eichmiller, et al. Sensory ability in the narwhal tooth organ system / The Anatomical Record nerve endings. Perhaps, on it, as on an antenna, the narwhal receives data on the state of affairs in sea water. But studies show that even without tusks, narwhals are perfectly oriented, so outgrowths do not seem to be necessary for survival.

And finally, the last theoryHow narwhals use their tusks / WWF: The tusk is used as a club to kill arctic cod with it. It sounds strange, but some narwhals use their fang for this purpose as well.

In general, scientists have not yet revealed the real purpose of the narwhal tusk.

4. How the jellyfish Turritopsis dohrnii manages to live forever

Usually the life cycle of any animal looks the same: birth, growth, development, maturation, wilting, death. But tiny jellyfishScience of the immortal jellyfish, Earth's longest living animal / BBC Science Focus Magazine only 4.5 mm long, called Turritopsis dohrnii, does not care about all these conventions.

When an adult decides that she is tired of this life, she simply takes it and is turningScience of the immortal jellyfish, Earth's longest living animal / BBC Science Focus Magazine into a baby polyp. Ripens anew and breeds, and then returns to the state of a self-respecting free-floating jellyfish. Exactly how many times she can do this, scientists still haven't counted. We have to admit that we are dealing with a potentially immortal being.

It is still unclear how the jellyfish manages to reverse its life cycle.

Known onlyS. Piraino, F. Boero, et al. Reversing the Life Cycle: Medusae Transforming into Polyps and Cell Transdifferentiation in Turritopsis nutricula (Cnidaria, Hydrozoa) / The Biological Bulletinthat she does this when environmental conditions become unpleasant for her: hunger, a sharp change in salinity and water temperature, injuries, and so on.

Perhaps if succeedScience of the immortal jellyfish, Earth's longest living animal / BBC Science Focus Magazine reveal the mechanisms that allow the jellyfish to rejuvenate, this will help people live longer and recover from severe injuries.

5. Why do giants live at the bottom of the ocean?

There is such a scientific term - deep-sea gigantism. It describes the propensity of marine organisms living in the darkest oceanic abysses to become large. No, it's just unrealistic healthyA. R. Palumbi, S. R. Palumbi. The Extreme Life of the Sea.

Judge for yourself. Giant isopod crayfish is a relative of ground woodlice. Only now it is under 45 cm long and weighs 1.7 kg. Giant isopods can generally grow up to 76 cm. The belt fish, also known as the herring king, reaches 11 m of “growth” and 272 kg of weight. The giant squid has a length of 13 meters - a ship, like the Kraken, will not be able to sink, but it will easily overturn the boat.

All sorts of Japanese spider crabs (the span of the front legs is up to 3 m) and giant amphipods (crayfish up to 34 cm long) also inspire horror and are capable of bringing arachnophobes to hysterics with just their appearance. And big red jellyfish and hairy cyanideans with two-meter domes generally resemble alien monsters.

With what joy the animals at the bottom become so huge, it is not clear.

First of all, the idea comes to mind that they are all fed protein there, but scientists suggest the opposite. reasonG. Gad. Giant Higgins‑larvae with paedogenetic reproduction from the deep sea of ​​the Angola Basin – evidence for a new life cycle and for abyssal gigantism in Loricifera? / Organisms Diversity & Evolution - lack of food. Well, the larger the body, the more effective it is to catch plankton, and there is little food at the bottom, so you have to grow a bigger mouth so that at least something gets there.

Another option is "lack" predatorsE. M. Harper, L. S. Peck. Latitudinal and depth gradients in marine predation pressure / Global Ecology and Biogeography — Wiley Online Library. It’s hard to hunt there, it’s dark, some big White shark does not dive deep. Here, in the absence of external stimuli, the local inhabitants swell to an indecent size.

Finally, there are suggestions that at depth the oxygen in the water is in more concentrated volumes and it is easier to absorb, that's the metabolism and rushing. Or low temperatureS. F. Timofeev. Bergmann's Principle and Deep‑Water Gigantism in Marine Crustaceans / Biology Bulletin of the Russian Academy of Sciences forced to increase the volume of the body in order to more effectively retain heat.

In general, why living creatures of monstrous dimensions swarm at the bottom of the sea, scientists have not yet understood. And to investigate these creatures is another task. It is not easy to go down to them, and to pull them to our surface is even more difficult, they are not used to surface pressure. We have to build theories at a distance.