Contrafreeloading is an observed

behavior Behavior (American English) or behaviour (British English) is the range of actions of Individual, individuals, organisms, systems or Artificial intelligence, artificial entities in some environment. These systems can include other systems or or ...

in which an organism, when offered a choice between provided food or food that requires effort to obtain, prefers the food that requires effort. The concept was introduced in 1963 by animal psychologist Glen Jensen. In his original study, around 200

rat Rats are various medium-sized, long-tailed rodents. Species of rats are found throughout the order Rodentia, but stereotypical rats are found in the genus ''Rattus''. Other rat genera include '' Neotoma'' (pack rats), '' Bandicota'' (bandicoo ...

s were given a choice between food in a bowl and a food dispenser which required that the rat step on the pedal a set number of times. In this experiment, Jensen found that the rats chose the foot pedal option as a function of the number of foot presses required to receive the food reward. Similar studies by Jensen and other researchers have since replicated his findings with

gerbils Gerbillinae is one of the subfamilies of the rodent family Muridae and includes the gerbils, jirds, and sand rats. Once known as desert rats, the subfamily includes about 110 species of African, Indian, and Asian rodents, including sand rats an ...

and other animals including canines,

mice A mouse (: mice) is a small rodent. Characteristically, mice are known to have a pointed snout, small rounded ears, a body-length scaly tail, and a high breeding rate. The best known mouse species is the common house mouse (''Mus musculus' ...

, rats,

birds Birds are a group of warm-blooded vertebrates constituting the class (biology), class Aves (), characterised by feathers, toothless beaked jaws, the Oviparity, laying of Eggshell, hard-shelled eggs, a high Metabolism, metabolic rate, a fou ...

fish A fish (: fish or fishes) is an aquatic animal, aquatic, Anamniotes, anamniotic, gill-bearing vertebrate animal with swimming fish fin, fins and craniate, a hard skull, but lacking limb (anatomy), limbs with digit (anatomy), digits. Fish can ...

monkeys Monkey is a common name that may refer to most mammals of the infraorder Simiiformes, also known as simians. Traditionally, all animals in the group now known as simians are counted as monkeys except the apes. Thus monkeys, in that sense, co ...

and chimpanzees. The only animal that did not display similar behavior was the domesticated

cat The cat (''Felis catus''), also referred to as the domestic cat or house cat, is a small domesticated carnivorous mammal. It is the only domesticated species of the family Felidae. Advances in archaeology and genetics have shown that the ...

, which preferred to be served."Domestic cats (''Felis catus'') prefer freely available food over food that requires effort"
Delgado et al 2021

References

Sources

The Free Food (contrafreeloading) Phenomenon: A Review and analysis
Ethology {{ethology-stub