Giant squid are one big happy interbeeding family.

[DavidBrown]

New genetic research shows that what were thought to be 3 species of giant squid appear to be one big panmictic population.

Apparently there may be hundreds of millions of giant squid cruising through the ocean depths. If true, that would be a refreshing change from the usual declining population story bedeviling many of our favorite species.

Giant squid population is one big happy species | Life | Science News

 

[Chlidonias]

that is an interesting article. A head-scratcher indeed.

 

[Chlidonias]

an article with some more information here: The Global Kraken – Phenomena: Not Exactly Rocket Science

The team found that the giant squid’s genetic diversity is incredibly low. Even though the individuals hailed from opposite corners of the world, they differed at less than 1 in every 100 DNA letters. For comparison, that’s 44 times less diverse than the Humboldt squid, which only lives in the eastern Pacific. In fact, the giant squid seems to be genetically narrower than any other sea-going species that scientists have tested, with the sole exception of the basking shark.

It’s possible that the adults are wandering nomads that swim over large areas, but that seems unlikely. Chemical analyses of their beaks suggest that they stick within a relatively contained patch of ocean. The alternative is that they go a-wanderin’ as larvae and youngsters.

And there’s one last, important caveat—the team’s conclusions are based on the mitochondrial genome alone. That’s useful for looking at things like diversity and ancestry, but the team still need to analyse the giant squid’s nuclear genome, which contains the vast majority of its DNA. Nuclear genomes have a habit of complicating the stories told by mitochondrial ones. Who knows what they will do for the giant squid?