The Development of Object Permanence in Turkeys (Meleagris gallopavo) and Muscovy Ducks (Cairina moschata)

Abstract

Object permanence, the understanding that an object continues to exist when it is out of sight, is one aspect of cognition that can help to ensure an animal’s survival by allowing it to keep track of both food and predators. Object permanence is not an all-or-nothing ability, instead occurring on a continuum. It is divided into six stages, with each stage building on the last. In avian species, the developmental timeline and final stage of object permanence reached can differ between species, possibly due to the effects of different environments and social structures on the evolution of this cognitive trait. In the current study two previously-unstudied avian species, turkeys (Meleagris gallopavo) and Muscovy ducks (Cairina moschata), were tested to determine the timeline of object permanence development and final stage of object permanence achieved using the Uzgiris and Hunt Scale 1 tasks. This scale is a set of 15 tasks that accurately assess which stage of object permanence an individual is in at a specific point in time. The Scale 1 tasks are also designed to easily compare the progression of object permanence development between species. Both wild type and domestic turkeys were tested in a preliminary attempt to determine whether domestication might affect the development and ultimate form of object permanence. Both the wild type and domestic turkeys could complete the tasks up to Task 3 (Stage 3 competence), while the Muscovy ducks were able to complete the tasks up to Task 4 (Stage 4 competence). These results support the idea that environmental pressures might affect the development of object permanence. This theory could be explored in future studies by administering the Scale 1 tasks to species either environmentally or genealogically similar to the Muscovy ducks.