A recent genetic study of preserved specimens of giant squid from around the world suggests that these animals are not only a single species, but in fact a single global population!
The Kraken as Seen by the Eye of Imagination by Edward Etherington
Now, this may not be a revelation to some. In fact most people have probably never wondered how many species of giant squid were lurking in the deep, but zoologists have been pondering this question for over one hundred and fifty years. Dutch naturalist Japetus Steenstrup orriginally first described this magnificent creature, which he concluded was the basis of many an ancient mythical sea monster, and bequeathed it a Latin name Architeuthis dux. Since then, only a handful of 'giant squid' have been found, but as many as eight separate species have been suggested. The current study goes a long way towards proving that this enigmatic giant represents a single species of a single population world wide.
This is really pretty astounding when you think that these creatures have been found as far away as Australia and the North Sea. How does a global population like this behave? How many of them are there? How long do they live? So many questions, and remarkably few answers, especially considering that most of what we know of this species is based on the odd individual washing ashore. In fact, it wasn't until 2004 that Japanese researchers captured the first images of a live squid. What we do know is that they can grow as long as 43 feet, they are thought to live between 300 and 1000 meters and they are preyed upon by sperm whales and occasionally pilot whales.
Anyway, the Japanese researchers who photographed the giant squid in 2004 were persistent, and after hundreds of dives over the next two years they finally captured video of another live squid in 2006. This is now all over the internet in some form or other, but there's a clip below.
I find it heartening that in our 'information age' there are still so many things left to discover about the world, and it would seem that many of those things can be found in the ocean.