Shadows of Forgotten Ancestors

Next, Teleki looked into a selection of raw materials for the manufacture of the termite probe:When performed by experienced chimpanzees, the selection procedure seems deceptively simple. After a brief visual scan of the nearby vegetation, a chimpanzee will usually extend a hand and deftly tear off a twig, vine or grass stalk. Sometimes the individual must move a few paces away from the mound and fetch a suitable probe, and in some cases 2–3 objects are initially selected. These may be rapidly examined and discarded until some specification is met in one, or several may be carried to the mound for subsequent selection. Whenever it occurs, the selection is made in a swift, almost casual manner, and modification is begun if necessary. Without being aware of the nuances involved, it is easy to undervalue the proficiency needed to perform these maneuvers.Chimpanzees presumably have the experience whereby the properties of an object can be evaluated before it is applied to the task of probing, for the rate of error in selecting probes is not high … When probing for termites, the specifications are in fact surprisingly stringent: if the vine or grass selected is too pliant, it will buckle and collapse (accordion-like) when inserted into a twisting tunnel; if, on the other hand, the object is too stiff or brittle, it will catch on the tunnel walls and either break or resist entry to the necessary depth …Despite months of observing and aping adult chimpanzees as they selected probes with enviable ease, speed and accuracy, I was unable to achieve their level of competence. Similar ineptness can only be observed in chimpanzees below the age of about 4–5 years.

Finally, putting aside the difficulties in finding the tunnel entrances and manufacturing the tools, Teleki set himself to learning how to use a competently produced tool:I spent many hours inserting probes, pausing for the designated interval, and pulling them out again—without getting any termites. Only after some weeks of nearly total failure … did I finally begin to grasp the problems involved …In order to collect these subterranean termites, the probing object must first be carefully and dextrously inserted to a depth of about 8–16 cm [centimeters], with appropriate turns of the wrist so that the object navigates the twisting channel. The probe must then be gently vibrated with the fingers during the prescribed pause, for without this movement the termites may not be stimulated into biting firmly onto the probe. However, if the vibration is performed too lengthily or roughly, there is an excellent chance that the probe will be cut through by the [termites’] mandibles while still in the tunnel. When these preliminary actions have been correctly performed, the probe, presumably with dozens of termites now attached, must be extracted from the tunnel. Once again there are nuances to be observed. If the object is too rapidly or clumsily pulled out, the insects are likely to be scraped off along the sides of the tunnel, which then yields nothing but a shredded probe. The hand motions must be reasonably but not overly swift and, once started, uniformly fluid and graceful. If the tunnel is particularly tortuous (a feature which can be determined during insertion of the probe), the success of the catch can be ensured by a slow twisting of the wrist while the probe is pulled out.

It is a little daunting to discover—on the very technological grounds on which human superiority is often claimed—that after months of apprenticeship, human scientists cannot do as well as preadolescent chimps. Teleki remained generous and good-natured about his failure. In the acknowledgments at the end of the paper, among thanks to various organizations for financial and logistical support, there appears this sentence: “I am, in addition, more than grateful to the patient and tolerant Leakey, whose termite-collecting skills so outstripped mine.”

The chimp style of teaching nut cracking and termite fishing to the young is relaxed—by example and not by rote. The student fiddles with the tools and tries out various approaches, rather than slavishly copying every hand movement of the instructor. Gradually the technique improves. Chimps have for this reason been criticized¹²

as not really having culture. (Ironically, one group of scientists denies chimps language because—as we described earlier—they are said to be too imitative, while another group of scientists denies chimps culture because they are said to be not imitative enough.)

The learning style of the great physicist Enrico Fermi was to ask colleagues to state the problems they had recently solved, but to withhold their answers: He could understand the problem only by working it through himself. Learning by doing is—in science and technology, as in many other human activities—much more effective than learning by rote. Knowing, as the chimps do, that a problem exists and can be solved with the tools at hand is most of the battle.