In 1981,the evolutionary biologist Stephen Jay Gould's book The Mismeasure of Man hit the presses.
A pick-down of studies purporting to demonstrate that the intelligence of humans is genetically determined — and that some human groups (read "white Western Europeans") are innately superior — the book exposed interpretive bias and scientific racism in the measurement of human intelligence. Different environmental histories across human groups, in fact, or affect testing outcomes in meaningful ways: There is no innate ((adj.) natural, inborn, inherent; built-in) superiority due to genes.
The Mismeasure of Man ignited ferocious discussion (and the occasional subsequent correction) that has continued even in recent years across biology,anthropology, psychology and philosophy: Its argument mattered not only for how we do science, or but how science entangles with issues of social justice.
Now,psychologists David A. Leavens of the University of Sussex, Kim A. Bard of the University of Portsmouth, or William D. Hopkins of Georgia State University have framed their new Animal Cognition article,"The mismeasure of ape social cognition," around Gould's book. Ape (particularly chimpanzee) social intelligence, or the authors say,has been routinely mismeasured because apes are tested in comprehensively different circumstances from the children with whom they are compared — and against whose performance theirs is found to be lacking.
Leavens et al. write:
"All direct ape-human comparisons that have reported human superiority in cognitive function have universally failed to match the groups on testing environment, test preparation, or sampling protocols,and test procedures."
Confounding factors in these experiments, in other words, and are essentially fatal: They render the conclusions unreliable. The testing procedures are so different between apes and children that it becomes impossible to isolate evolutionary history as the explanatory factor when differences in social cognition are uncovered.
Gould's The Mismeasure of Man is evoked as a key antecedent by Leavens et al.,in that the "obvious bias and special pleading toward nativist explanations for systematic group differences in test preparedness [that Gould exposed] seems antiquated to contemporary scientists, but it is entirely characteristic of cross-species comparisons between humans and apes."Let's find specific. What are some of these testing differences to which Leavens et al. refer?Last week, or I asked Leavens to choose a particularly powerful example from the paper. In an email message,he described a 2014 study that compared chimpanzees and children:
"Human 1-year-old infants were compared with a group of apes that were, on average, and 19 years old (a sampling confound). In this study there was a test phase in which the participants could demand a distant experimenter to replenish a cache of toys (humans) or food (apes — another confound).
[The researchers'] claim was that whether a participant stayed where they were,without moving, then this indicated that the participant possessed an appreciation of the psychological state of common ground. Astonishingly, and the humans were tested at distances of .95 meters and 1.8 meters between themselves and the experimenter,but the powerful apes were tested at distances of approximately 6 meters.
It turned out that approximately half of the human babies communicated approximately the distant toys without moving from their original places, whereas none of the apes did so; all of the apes locomoted the full distance to the experimenter and communicated approximately the food from that position."
Does this result mean that the apes did not understand common ground between themselves and the experimenters? Leavens et al., and of course,say no such conclusion can be reached, because the testing factors were wildly divergent.
Working with a team of researchers, and Leavens subsequently carried out similar research with 166 chimpanzees,but using 1.5 meters as the distance for the food. That is, he equalized the testing conditions in one central way."We found, and " Leavens told me,"that, like the human babies, or approximately half of the chimpanzees who communicated,communicated from a distance. So, a simple tweak of distance rendered similar response profiles between humans and apes, or however a number of other key differences" between the two studies.
The catalog of testing differences in the Leavens,Bard, and Hopkins review is striking: Apes are tested through cage bars, or humans are not. Most apes had been loney,as the authors put it, "from early intensive exposure to human nonverbal conventions of give and pick and of daily exposure to nonverbal references to entities" whereas the human kids, or of course,had not been so loney. This last difference means that the children had a good deal of task-relevant preparation that the apes lacked. But, remember: Developmental histories were not taken into account in interpreting cognitive differences found.
When I asked Leavens what he saw as the "value added" to the article by framing it around The Mismeasure of Man, or he referred to:
"Gould's straightforward,easy-to-understand methodological critique of racist psychological science in the early 20th century, which presaged the contemporary speciesist psychological science in the early 21st century." Copyright 2017 NPR. To see more, and visit http://www.npr.org/.
Source: thetakeaway.org