Thanks, but I’ll wait for the shrimp
Cuttlefish eat less for lunch when dinner looks better.
By Nick Carne
When it comes to planning the day’s meals, cuttlefish appear to have remarkably sharp cognitive abilities.
British research shows that they will decide to eater fewer crabs during the day if they know that shrimp – their favourite food – will be available in the evening.
In experiments, it took European common cuttlefish (Sepia officinalis) only a few days to learn to tell whether shrimp was on the menu, and to adapt accordingly.
When the researchers reliably provided one shrimp each evening, the cuttlefish became more selective during the day.
But when they were provided with evening shrimp on a random basis, they became opportunistic and ate more crabs when they could.
When conditions changed, they changed their foraging strategy to match.
"This is a very complex behaviour and is only possible because they have a sophisticated brain," says Pauline Billard from the University of Cambridge, first author of a paper in the journal Biology Letters.
The first stage of the study was to be sure that cuttlefish do have strong food preferences, despite having a varied diet, which also includes fish and squid.
The researchers tested 29 cuttlefish five times a day for five days by putting crab and shrimp an equal distance away and watching what was eaten first. All showed a preference for shrimp.
Billard says cuttlefish hatch with a large central nervous system, which enables them to learn from a young age. They can remember events from the past and use this information to adjust their behaviour in anticipation of the future.
However, the researchers stress that at this stage they “cannot validate whether this future-dependent foraging behaviour observed in cuttlefish is underpinned by their ability to plan for the future”.
“In order to determine whether cuttlefish foraging behaviour qualifies as future planning, we still need to test one critical criterion – are cuttlefish behaving independently of their current motivational state (i.e. desire to eat shrimps in the present moment),” they write.
“Nevertheless, these results represent a promising way for further studies on flexibility and future-oriented behaviour in cephalopods.
“Given that cephalopods diverged from the vertebrate lineage approximately 550 million years ago, finding comparable future-oriented abilities in cuttlefish might provide valuable evolutionary insight into the origins of such a complex cognitive ability."