Friday Squid Blogging: The Reproductive Habits of Giant Squid


A recent study on giant squid that have washed ashore along the Sea of Japan coast has raised the possibility that the animal has a different reproductive method than many other types of squid.

Almost all squid and octopus species are polygamous, with multiple males passing sperm to a single female. Giant squids were thought to have a similar form reproduction.

However, a group led by Professor Noritaka Hirohashi, 57, a professor of reproductive biology in the Faculty of Life and Environmental Sciences at Shimane University suspects differently.

They examined 66 sperm “bags” attached to five different locations on the body of a female that washed ashore in Ine Town of Kyoto Prefecture in 2020, and found that all of them were from the same male.

It is rare for a female with sperm attached to be found, and further verification is needed, but the study’s results indicate that giant squid, unlike other squids, may be “monogamous.” That is, females may receive sperm from only one certain male. Hirohashi and his colleagues published their findings in an international scientific journal in July of 2021.

As usual, you can also use this squid post to talk about the security stories in the news that I haven’t covered.

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