Nature is made up of amazing and intriguing creatures. One of the most intriguing is perhaps the octopus. Some even think they might be aliens. A mystery that has long eluded scientists is the octopus’ self-destruction after mating. For years, scientists have wondered why octopuses torture each other after mating.
Now, after all this time, researchers may finally have the answer.
We’ve known for a long time that mother octopuses torture and sometimes even eat each other when their eggs are close to hatching. While they aren’t the only creatures in the wild that die after mating, they have one of the most gruesome approaches to the process.
For years, scientists have tried to find out why octopuses act this way after mating. Now, a new study published in the journal Current biology could provide the answers we were all looking for. Researchers say mother octopuses torture each other after mating due to chemical changes that occur when the mother lays her eggs.
A 1977 study found that a set of glands near the octopus’ eyes were responsible for the mechanism that caused the self-destruction. Researchers found that these glands produce steroid hormones in the octopus. And when the mother has laid her eggs, those glands go into overdrive. These are the steroids that cause octopuses to torture themselves.
Why do octopuses torture themselves after mating?
In total, the researchers discovered three distinct chemical shifts that occur at the same time as the mother octopus lays her eggs. First, there is an increase in pregnenolone and progesterone. These two hormones are commonly associated with reproduction in a host of creatures. It is therefore not surprising to see them here.
Then they saw a second change when the octopus started producing higher levels of 7-dehydrocholesterol, or 7-DHC. It is a building block of cholesterol, and humans also produce it when making cholesterol. However, it may be one of the chemical changes causing octopuses to torture after mating.
7-DHC can be a toxic compound. That’s why humans don’t keep it in their system for long. The researchers also noted that the optic glands began to produce more of the compounds used in bile acids. Octopuses do not use the same type of bile acids as humans and other animals, but they are the building blocks of those acids.
Researchers believe these chemical changes come together and cause the octopuses to torture themselves. The exact reasoning behind why these changes occur, or why the octopus’ body is designed this way is still unclear. Z. Yan Wang, assistant professor at the University of Washington, said Live Science that this could be a way to protect young octopuses.
Octopuses are naturally cannibalistic creatures. As such, the torture and subsequent death caused by these changes could be a way to naturally cull the older generation to protect the young ones before they can be killed and eaten by the older octopuses.