Natural selection has given chimps a phenomenal short term memory. Japanese researchers have found that if you flash the average chimpanzee a screen of numbers in different locations up to nine, then cause the screen to disappear, the chimp can reconstruct the location of the numbers in numerical order. One especially quick chimp can remember the order and location of 19 numbers!
This skill is related to living in trees (identifying and locating the position of different fruits and branches in trees). It may also be useful in identifying and sizing up a pack of rival chimps (fight or flight). In any event, only savants can perform the trick among humans. Neither you nor I could ever hope to outperform a chimp on this particular test of intelligence.
One thing impressive here is the certainty with which chimps respond to this test. There are no conflicted Hamlets here. If they could talk, they’d respond to three consecutive screens this way:
It’s that pattern, it’s that one, it’s that one.
They’d say it that fast. Why? Because they don’t doubt their intuition for a second. They don’t think about it. They don’t fret. They just know the right answer. If they had speech, they wouldn’t have to talk about it or reason with others about it. We might say that chimps have a special mental organ that humans don’t have, a sensus numericatis (a numerical ordering and location sense).
Which raises the issue of religion. John Calvin claimed that Christians have a special organ that is damaged or cannot be found in the damned: a sensus divinitatis (a divine sense; a divine detection device). The way the chimps know the order and position of numbers is the way Christians like Calvin know God: they have a pattern detector. The sheep know the Shepherd’s voice. They recognize His face. He calls them by their name.
The difference of course is that there is publicly verifiable evidence for the chimp’s unique numerical ordering sense while Christians like Calvin show no evidence whatsoever they really detect anything that the rest of us don’t.
Below is Richard Dawkins pointing to another pattern all humans ought to be able to recognize immediately: the pattern of branching lineages and common descent that we can readily see when comparing genomes. If chimps are adept at moving through the branches of physical trees, we are adept at identifying the branchings of the evolutionary tree. Call it our sensus evolutionitatis.