The elusive vampire squid wears its red flesh like a voluminous cape. Billowing in the depths, the animal’s velvety exterior almost seems to enshroud some deeper truth of the phantasmal creature, which says merely in its choice of habitat — the pitch-black, oxygen-starved layer of the ocean — that it would prefer to be left alone.
Now, a European team has sought to understand how the cephalopod has managed in such a hostile environment. They studied a rare, 30-million-year old fossil of a vampire squid relative and possible ancestor, Necroteuthis hungarica. The fossil was rediscovered in 2019, more than six decades after it was believed to have been destroyed in a museum fire during the Hungarian Revolution. The team’s findings were published recently in the Nature journal Communications Biology.
“We were surprised that the specimen exists, as it’s been considered lost for a long time,” study lead author Martin Košťák, a paleontologist at Charles University in Prague, said in an email. “This was probably the most exciting moment.”
There are benefits to living in bleak environments like the one Vampyroteuthis infernalis now inhabits. For one, less life means there are fewer predators seeking the creature out. There’s also less competition for its food sources, which tend to be the “marine snow” of organic matter that drifts down from farther up in the ocean, as a team from the Monterey Bay Aquarium Research Institute discovered when they observed a living vampire squid via their remotely operated submersible.
Using scanning electron microscopy and geochemical analysis, Košťák’s team managed to confirm the initial identification of the fossil as a vampire squid, though a different genus and species from the red animal we know today. (Technically, vampire squids are not squids at all. They’re cephalopods, like squids and octopuses, but they lack the pair of longer tentacles that true squids have.)
The fossil animal was slightly bigger than the modern, foot-long vampire squid. Looking at the fossilised sediment ensconcing the ancient cephalopod, the team determined that the creature was already inhabiting a low-oxygen environment in the Oligocene epoch, some 30 million years ago. But, while inspecting rocky layers outside of Budapest where the fossil was excavated, the research team found fossil plankton that would thrive in shallow seas, a region today’s vampire squids can’t stand.
Košťák said that though the ancient squid was already adapted to low-oxygen conditions, it lived in a much shallower sea than its modern relatives.
“There is no evidence for when and where these lineages diverged,” he said, noting there is “too poor a fossil record to say.” But it’s possible that today’s vampire squid coexisted with its long-extinct relative. What is certain, Košťák said, is that “the living vampire squid is actually a ‘living fossil,’ a descendant of Jurassic cephalopods.”
The team suggested that the ancient squid’s adaptation could have helped the species endure mass extinctions that snuffed out other branches on the tree of life, such as the end-Cretaceous event that saw the demise of non-avian dinosaurs. Being able to get by on less is certainly a winning evolutionary strategy.