Finding an incubating octopus species for more than 4 years

(University of Rhode Island - URI) and Monterey Bay Aquarium Research Institute (Monterey Bay Aquarium Research Institute) have observed an octopus living in the deep sea incubate its eggs for 4 1/2 years - longer than any other known animal.

During this time, the female octopus keeps its eggs clean and protects the eggs from predators. This analysis shows an evolutionary activity that balances the benefits for young octopus to have more time to grow inside the eggs, and their mother's survival ability in the years of scarcity or absence of consciousness. eat.

'This study reflects that we know very little about deep sea life and about life in general,' said Brad Seibe, a URI professor of biological sciences. 'From the aquatic creatures living in the water, we have developed narrow ideas about the capabilities of animals'.

Based on previous research, Seibel has speculated that eggs of some octopus species living in the deep sea may take several years to develop, and this new observation has provided a perfect opportunity to test that hypothesis. . ' While we anticipate a long development period, we are not very confident about that prediction and the results are still surprising'.

Several months in the past 25 years, a group of Monterey Bay researchers led by Bruce Robison has been conducting deep-sea organisms research at a Monterey Canyon area deep research site that they called Midwater 1 .

In May 2007, one such study, the researchers found that a female octopus was hugging a rocky edge just above the surface of the reef, located at a depth of about 4,600 feet. (about 1,380m). This octopus, belonging to a species called Graneledone boreopacifica , has not yet appeared here in the previous dive, which the team conducted in April 2007.

Over the past four and a half years, the team has dived into this position all 18 times. Each time, they all saw the female octopus, they could be sure it was because of its special scars. As the years passed, the octopus's translucent eggs grew bigger and the researchers could see the growing octopus inside. At the same time, the mother octopus lost weight and her skin became wrinkled and pale.

Never have researchers seen a mother octopus leave eggs or eat anything. It's not even attracted to small crabs and shrimps crawling or swimming around, as long as they don't touch its eggs.

The last time the researchers saw that hatched octopus was in September 2011. After a month when they returned, they could no longer see the octopus there. When the researchers wrote an article published this week in the journal PLOS ONE, 'the face of the rock that the octopus has hatched has a lot of empty eggshells left'. After counting the remaining empty eggshells, they estimated that the female octopus had hatched about 160 eggs.

Most octopus lays only one batch of eggs and dies around the time that their eggs hatch.Graneledone boreopacifica octopus eggs are shaped like droplets of the size of small olives. When young animals grow in eggs, they need a lot of oxygen. This means that the mother octopus must constantly wash the eggs in clean, oxygen-rich seawater and keep the eggs from getting dirty and covered with mud or debris. It must also ensure safety for eggs, protect eggs from predators.

Because the octopus in the eggs are long, when they hatch they have enough of their survival abilities and can hunt small prey themselves. In fact, the G. boreopacifica octopus's offspring are larger and better developed than the offspring of any other squid or octopus.

Prolonged incubation time represents an evolutionary challenge, especially for animals such as octopuses, creatures that do not live long. As the authors emphasized in their article 'The trade-off in the reproductive strategy of deep-sea octopus, it is a trade-off between the ability of the mother octopus to endure a period of incubation. prolonged eggs and competitiveness for their young ' . Graneledone boreopacifica has produced more fully developed baby octopus, giving them the advantage of surviving.

This study shows that, in addition to the record for the longest incubation time, Graneledone boreopacifica may be one of the longest living molluscs (soft body groups including octopus, squid and close relatives) . Most squid live in shallow water and the ink only lasts one or two years.'The final fate of the hatched female octopus is inevitable' , the researchers wrote in the article, 'But in the first example of this deep-sea mollusk, Incubation also shows that this octopus has a life expectancy far exceeding the predicted life expectancy of other molluscs. '