Octopus!
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So, why are cephalopods kicking butt when pretty much everything else in the oceans is dying? Doubleday and her co-authors are still investigating, but they suspect it has to do with rapid population turnover rates. “Cephalopods tend to boom and bust—they’re called the weeds of the sea,” Doubleday said. “If environmental conditions are good, they can rapidly exploit those conditions because they grow so fast.”
One reason environmental conditions might have improved is that humans are picking off cephalopods’ main competitors—predatory fish. Other large-scale changes like global warming could also be playing a role. “I don’t think it’s any one single factor,” Doubleday said. “But something’s changing on quite a large scale that’s giving cephalopods an edge.”
Sounds like an Axis of Oceanic Evil to me.
More seriously, is this connected to climate change? Maybe.
As the oceans continue to change, the long-term fate of all marine organisms remains uncertain. For instance, early laboratory evidence suggests that ocean acidification might impair the development of some cephalopods. And as squid and octopuses become a larger part of human diets, we’re harvesting more cephalopods from the sea than ever before.
Another strange possibility is that cephalopods will become too weedy and run out of food. If that happens? “They’re highly cannibalistic—they might start eating each other if they overgrow,” Doubleday said.
In short, it’s too early to predict whether octopuses will continue to boom or whether the oceans will devolve into a frenzied cannibalism fest. Still, if an intelligent race of tentacled underwater beings winds up outmaneuvering us and taking over the planet, we can’t say there weren’t warning signs.