Relative numerousness judgment and summation in young, middle-aged, and older adult orangutans (Pongo pygmaeus abelii and Pongo pygmaeus pygmaeus).

Abstract

The ability to select the larger of two quantities ranging from 1 to 5 (relative numerousness judgment [RNJ[) and the ability to select the larger of two pairs of quantities with each pair ranging from 1 to 8 (summation) were evaluated in young, middle-aged, and older adult orangutans (7 Pongo pygmaeus abelii and 2 Pongo pygmaeus pygmaeus). Summation accuracy and RNJ were similar to those of previous reports in apes; however, the pattern of age-related differences with regard to these tasks was different from that previously reported in gorillas. Older orangutans were less accurate than the young and middle-aged for RNJ, and summation accuracy was equivalent among age groups. Evidence was found to suggest that the young and middle-aged based their selection of the largest quantity pair on both quantities within each pair during the summation task. These results show a relationship between subject age and the quantitative abilities of adult orangutans.

Adaptive numerical competency in a food-hoarding songbird

“…Moreover, their performance over the entire number range is related to the ratio between quantities and, to some extent, total set size (e.g. Beran 2004Beran , 2007Anderson et al 2007;Hanus & Call 2007). Different corroborative evidence that accuracy in numerical judgements smoothly decreases with increasing magnitude, rather than breaking down after a set size limit of four items, has been documented in experiments investigating numerical ordering tasks (e.g.…”

Elephant cognition in primate perspective

“…All elephants chose the basket containing the larger amount, significantly more often than expected by chance, performing at 72-82% accuracy. As in the first experiment, the elephants did not exhibit disparity or magnitude effects, in which performance declines with a smaller difference between quantities, or the total quantity increases, respectively, in striking contrast to the performance of great apes and even human infants in similar relative quantity judgement tests (see Anderson, Stoinski, Bloomsmith, & Maple, 2007;Beran, 2001;Boysen, Bernston, & Mukobi, 2001;Feigenson, Carey, & Hauser, 2002;Xu & Spelke, 2000). It is not yet known what cognitive mechanisms underlie the Asian elephants' numerical ability, but it may be that elephants are able to keep track of a larger number of items in immediate, working memory than can great apes including humans, and that when relative quantity judgements of larger numbers of items are explored then disparity and magnitude effects will emerge.…”

Comparative Pathology of Aging Great Apes

“…9,10,139,252 In aged chimpanzees and orangutans, only certain types of tasks were affected-such as social cognition, some motor skills, and, in the case of orangutans and gorillas, relative numerousness judgment.…”

“…280,281 Orangutans are considered to be ''older adults'' at 35 y in some studies and 40 y in others. 9,155,233,280 Physiologic and pathologic states associated with aging in humans and animals include the following: hair loss or graying, generalized frailty, loss of bone (osteopenia and osteoporosis), loss of muscle mass and strength (sarcopenia), arthritis, dental attrition and tooth loss, reproductive senescence, loss of cognitive function and other neurodegenerative conditions (including sensory impairment: hearing, smell, taste, and vision [eg, cataracts, macular degeneration]), cardiovascular disease (including hypertension), endocrinopathies (eg, type II diabetes/metabolic syndrome), renal disease, decline of immune functions, and increased occurrence of many types of neoplasms. 13,125,283 Any one individual will not demonstrate all facets of the aging phenotype but will rather be a mosaic of various aspects of molecular, cellular, and organ changes unique to that aged individual.…”