Poultry are domesticated species of birds. Birds were domesticated for eggs (chickens, ducks and geese), meat (chickens, ducks, geese, turkeys, ostriches, emus, pigeons and game birds) or other uses including feathers (ostriches, ducks and geese), leather (ostriches), specific oils (ostriches, emus), cock-fighting (chickens) and homing (pigeons). Table 1 summarizes the approximate time when and...

over long distances has been studied extensively. In a typical homing experiment, pigeons are brought from their loft to release sites ranging from a few to tens of kilometres away, and their homing performance is measured. Standard parameters measured include the direction taken by the birds at the release site, the time until they vanish from the release site, and the time they take to return...

Parallel experiments with rats and pigeons examined reasons for previous findings that in choices with probabilistic delayed reinforcers, rats' choices were affected by the time between trials whereas pigeons' choices were not. In both experiments, the animals chose between a standard alternative and an adjusting alternative. A choice of the standard alternative led to a short delay (1 s or 3 s...

If a group of foragers distributes among resource patches according to the ideal free distribution, the relative number of foragers in each patch should match the relative amount of resource obtained there, unless deviations arise from factors such as incomplete information or interforager interference. In analogy to individual choice, such effects may produce undermatching—group distribution f...

Atherosclerosis-susceptible White Carneau (WC-2) pigeons were compared with atherosclerosis-resistant Show Racer (SR-39) pigeons in terms of hepatic and aortic biotransformation and bioactivation of benzo[a]pyrene (B[a]P). Following pretreatment of the two strains with 3-methylcholanthrene (MC, 40 mg/kg), WC-2 hepatic 9000 X g supernatant fractions (S-9) exhibited consistently greater increases...

Pigeons' choice between reliable (100%) and unreliable (50%) reinforcement was studied using a concurrent-chains procedure. Initial links were fixed-ratio 1 schedules, and terminal links were equal fixed-time schedules. The duration of the terminal links was varied across conditions. The terminal link on the reliable side always ended in food; the terminal link on the unreliable side ended with...

When humans gambling they choose an outcome that has high value but a low probability of occurrence over a more favourable high probability outcome of lower value (not gambling). Similarly, pigeons show a preference for an alternative that occasionally provides a signal for reinforcement over a more optimal alternative that always provides a signal for a lower probability of reinforcement. Two ...

Coevolution is evolution in one species in response to selection imposed by a second species, followed by evolution in the second species in response to reciprocal selection imposed by the first species. Although reciprocal selection is a prerequisite of coevolution, it has seldom been documented in natural populations. We examined the feasibility of reciprocal selection in a simple host-parasi...

Retinotopic encoding is preserved in primate visual cortex. However, several physiological and psychophysical studies have revealed that visual processes can be disengaged from retinotopic coordinates. We examined whether this non-retinotopic processing is common to humans and pigeons, two visually dominant vertebrate species with similar retinotopic organizations in their brains. We used a var...

BACKGROUND An experiment with pigeons was conducted for 46 months in order to test the multiple-exemplar training (MET) hypothesis of symmetry derivation. According to this hypothesis, symmetry is progressively derived after an extensive training of multiple examples of direct and inverse relations among arbitrary stimuli. METHOD Four pigeons were given extensive training in direct (e.g., A1-...