Cuttlefish are able to remember what, where, and when specific events happened up until their last days of life. Researchers suggest this is the first evidence of an animal whose memory of specific events does not deteriorate with age, unlike our own.
Cuttlefish Remember Details Of Their Last Meal, Study Finds, The Guardian, 18 August 2021
Cuttlefish have one of the largest brains among invertebrates and can remember what, where, and when specific things happened right up to their final days of life, according to new research.
The cephalopods – which have three hearts, eight arms, blue-green blood, regenerating limbs, and the ability to camouflage and exert self-control – only live for roughly two years.
As they get older, they show signs of declining muscle function and appetite, but it appears that no matter their age they can remember what they ate, where and when, and use this to guide their future feeding decisions, said the lead study author, Dr Alexandra Schnell from the University of Cambridge.
This is in contrast to humans, who gradually lose the ability to remember experiences that occurred at a particular time and place with age – for instance, what you ate for lunch last Wednesday. This “episodic memory” and its deterioration is linked to the hippocampus, a seahorse-shaped organ in the part of the brain near our ears. Cuttlefish, meanwhile, do not have a hippocampus, but a “vertical lobe” associated with learning and memory.
During training, the performance of both groups was comparable, she said. “In the test phase, the older cuttlefish (the equivalent of a human in their 90s) actually outperforms the younger cuttlefish.”
Malcolm Kennedy, professor of natural history at the University of Glasgow, said it was refreshing to come across another case where aspects of animal cognition can be as advanced as our own, despite huge evolutionary time separation and a nervous system constructed completely different from ours.
“The pedestal upon which humans place themselves in terms of neurological abilities continues to crumble. It is just that other types of animals perform similar functions differently,” he said.