Climate Change Could Shrink the Brain of One of the Ocean’s Most Intelligent Creatures

Oceans absorb up to 30% of emitted carbon dioxide, according to the National Oceanic and Atmospheric Administration (NOAA). That has raised ocean acidity—a direct result of CO2 absorption—by 30%. The effect has been especially damaging on corals, oysters, and free-swimming snails and slugs. NOAA predicts that acidification will increase by 100% to 150% by the end of this century. As that happens, whole populations of squid are likely to suffer the same change as the ones in the experiment, and that could dramatically affect the structure of their societies, especially since it’s the optic regions of the brain that suffer the greatest damage. “If they are experiencing challenges in how to interpret visual stimuli, amongst other stimuli, it would seem that reliance on visual displays for communication and mating rituals could be impacted,” Allen says. 

The loss of or injury to any animal as a result of human activity is a tragedy, but it’s particularly so when the creatures being harmed are smart, sentient, clever, complex. The squid sit atop the invertebrate world; humans could yet push them over.