When scientists from Stanford University and the National Geographic Society strapped a video camera to a Humboldt squid, they discovered a surprising thing about the human-sized cephalopods, which are known for their aggressive predatory behaviour: they also love to have a chat.
The Humboldt squid, like many other species of squid, has bioluminescent photophores in its skin that can rapidly change colour. Changes in colour are used for camouflage but also, as it turns out, for communication.
On analysing the footage they retrieved from the squidcam, the researchers noticed that a specific skin pattern – rapid whole-body colour changes from red to white and back, occurring between two and four times a second – only happened when in the presence of other squid. The conclusion? The flashing represents a form of “intraspecific signalling”, or squid-to-squid communication.