Cuttlefish can pass the marshmellow test.

Cephalopod mullusks like octopuses or cuttlefishes show remarkable intelligence. My most engaged and soothing viewing experience during the pandemis has been watching "My Octopus Teacher" on Netflix. Now recent work pointed to by Greenwood shows that cuttlefish can pass the famous marshmellow test, forgoing immediate gratification if experience has shown that waiting produces a larger reward:

Decision-making, when humans and other animals choose between two options, is not always based on the absolute values of the options but can also depend on their relative values. The present study examines whether decision-making by cuttlefish is dependent on relative values learned from previous experience. Cuttlefish preferred a larger quantity when making a choice between one or two shrimps (1 versus 2) during a two-alternative forced choice. However, after cuttlefish were primed under conditions where they were given a small reward for choosing one shrimp in a no shrimp versus one shrimp test (0 versus 1) six times in a row, they chose one shrimp significantly more frequently in the 1 versus 2 test. This reversed preference for a smaller quantity was not due to satiation at the time of decision-making, as cuttlefish fed a small shrimp six times without any choice test prior to the experiment still preferred two shrimps significantly more often in a subsequent 1 versus 2 test. This suggests that the preference of one shrimp in the quantity comparison test occurs via a process of learned valuation. Foraging preference in cuttlefish thus depends on the relative value of previous prey choices.