Can Black‐and‐White Ruffed Lemurs (Varecia variegata) Solve Object Permanence Tasks?

Abstract

We examined object permanence in black-and-white-ruffed lemurs (Varecia variegata) at Zoo Atlanta. A series of visible and invisible displacement tasks with suitable controls were presented to five adult subjects. Subjects performed significantly above chance on all regular tasks, except for the double invisible displacements. Subjects failed visible and invisible controls. Failure on the control trials did not appear to be because subjects used the "last box touched" strategy (subjects did not choose the last box touched significantly more than expected by chance). However, a substantial percentage of choices was made to the last box touched by the experimenter. There was no significant difference between this percentage, and the percentage of choices made to the baited box (on both visible and invisible controls), which indicates that subjects were drawn to both boxes which the experimenter visited/touched, and thus failed the controls. Based on the results from the present study, we believe that there is no evidence that black-and-white ruffed lemurs understand visible and invisible tasks in the traditional object permanence battery.

Horses Solve Visible but Not Invisible Displacement Tasks in an Object Permanence Paradigm

“…In view of our current results, we thus cannot conclude that horses comprehend invisible displacements. Similar results of failing to comprehend invisible displacements have been found in other species, including dolphins ( T. truncatus ; Jaakkola et al, 2009 ), dogs ( C. familiaris ; Collier-Baker et al, 2004 ; Fiset and LeBlanc, 2007 ), rhesus monkeys ( M. mulatta ; de Blois and Novak, 1994 ), prosimians ( Deppe et al, 2009 ; Mallavarapu et al, 2013 ), and cats ( F. catus ; Doré, 1986 ; Dumas and Doré, 1989 ). It has been argued that most invisible displacements in natural conditions could actually be partly solved by a reliance on external cues; for example, moving objects or subjects – food items, predators, or conspecifics – can also be detected through the use of other sensory cues, and usually reappear near to where they were last seen by the individual ( Jaakkola, 2014 ).…”

“…Other species succeeded in tasks involving Stage 5, but not 6. These include rhesus monkeys ( Macaca mulatta , e.g., de Blois and Novak, 1994 ), prosimians (e.g., Deppe et al, 2009 ; Mallavarapu et al, 2013 ), dolphins ( Tursiops truncatus , Jaakkola et al, 2009 ; Singer and Henderson, 2015 ), dogs ( Canis familiaris , e.g., Collier-Baker et al, 2004 ; Fiset and LeBlanc, 2007 , but see also Gagnon and Doré, 1992 , 1993 , 1994 ), macaws ( Ara militaris , Wrape and Hammonds, 2019 ), and cats ( Felis catus , e.g., Doré, 1986 ; Dumas and Doré, 1989 ).…”

Macphail’s Null Hypothesis of Vertebrate Intelligence: Insights From Avian Cognition

“…Its final stage requires an understanding of invisible displacement: that is, tracking a container which presumably contains the hidden object as it moves behind a series of screens or occluders, and guessing where it may have been left once the container is shown to be empty. The great apes ( de Blois et al, 1998 ; Call, 2001 ; Collier-Baker and Suddendorf, 2006 ; Collier-Baker et al, 2006 ; Mallavarapu, 2009 ), corvids ( Pollok et al, 2000 ; Zucca et al, 2007 ; Hoffmann et al, 2011 ; Ujfalussy et al, 2013 ), and parrots ( Pepperberg and Funk, 1990 ; Pollok et al, 2000 ) succeed at the final stage of object permanence, even though other species of both birds and mammals do not. Four species of lemurs ( Deppe et al, 2009 ; Mallavarapu, 2009 ) succeed only at visible displacement tasks, where the reward can be seen as it moves between two or more occluders.…”

Do animals understand invisible displacement? A critical review.

“…To date, two studies have tested prosimians (specifically lemurs) on a series of visible and invisible displacement tasks (Deppe et al, 2009; Mallavarpu, Perdue, Stoinski, & Maple, 2013). The lemurs uniformly passed the visible, but failed the invisible displacement tasks (Deppe et al, 2009) or failed the control for associative strategies (Mallavarpu et al, 2013).…”