Dryopithecus, the tool-wielding ape

For most of anthropology's history tools had been thought to be the exclusive hallmark of humanity. That only our species could use and manufacture tools was a sign of our superiority, be it the result of evolution or divine fiat, at least until it was discovered that apes could make tools, too. Though anecdotal accounts of tool use by primates had existed for centuries it was Jane Goodall's research at Gombe in Tanzania that truly shattered the "Man the Tool-Maker" image. When told of her discovery Louis Leakey is said to have responded "Now we must redefine tool, redefine Man, or accept chimpanzees as humans."

This was not the first time a tool-wielding ape threatened to take Homo sapiens down a peg. At the end of the 19th century numerous physical anthropologists were debating whether an extinct Miocene ape called Dryopithecus could have been a tool user. The argument centered around some shards of stone and cut bones from the Miocene rock of France.

Before diving into this debate, however, something needs to be said about the way Deep Time was understood. Today we regard the Miocene as having stretched from about 23 million years ago to about 5.3 million years ago but this was not always so. In the 1870's, 1880's, and 1890's there was no way to obtain absolute dates for geological strata like we have now. Relative dates could be obtained by carefully examining strata and the fossils found within but this was certainly not a foolproof method. Because of this fossils or artifacts found where they were not expected had the potential to throw scholars into a quandary.

Such were the mid-Miocene flint shards and cut-marked manatee rib from Thenay in France. Similar relics had been found elsewhere but in much younger deposits. No one had yet found any sign that humans, the only toolmaking organism known, had lived at so ancient a time. Perhaps the tools were made by a rude human precursor that had already diverged from the line leading to modern apes, a true "Dawn Man."

The English geologist William Boyd Dawkins did not think so. He followed the argument put forward by the French paleontologist Jean Albert Gaudrythat the Miocene deposits of France contained a unique fauna that had largely gone extinct. If humans had existed during this time why should they be unchanged while the animals around them evolved or perished.

The problem was that this did not resolve the question of who had made the tools and cut the bone. To resolve this problem Gaudry and Dawkins argued that the extinct ape Dryopithecus had been responsible for these signs of industry. As John Fiske wrote in his article "Europe Before the Arrival of Man";

... for although it is not known that any existing apes are in the habit of chipping flints or cutting bones, yet it is not impossible that the dryopithecus may have somewhat surpassed the present apes in intelligence.

This would make even more sense if Dryopithecus turned out to be a human ancestor, or at least closely related to us.

Not everyone was convinced by the arguments of Dawkins and Gaudry. In Man and His Handiwork the English natural history writer John George Wood responded;

To my mind, there never was a feebler attempt at reasoning. It is a pure assumption that, because actual personal relics of man have not yet been found in the mid-Miocene strata, and that no other then- existing mammal has survived, man never existed in that epoch. Exactly the opposite conclusion ought to have been drawn, i.e., that the presence of a tool, or of marks made by a tool, is a proof that the tool was made by man, and used by man. What could an ape want with a flint-flake, and why should a terrestrial and vegetarian animal cut the ribs of an aquatic mammal? The imperfection .of the tool or its work signifies nothing, and the flint-flake and scratched rib are as absolute proofs of man and his handiwork as if a chronometer watch or a Nasmyth's hammer had been discovered in the same strata.

The question of tool-using apes also raised the question of why they had not inherited the earth. Surely if they were smart enough to make and use tools they would have continued the onward and upward march of evolution and claimed the world for themselves. This would have left no room for our own ancestors. (This might seem confusing given our current understanding of our own evolution but at the time the idea that there was a line of ancient proto-humans distinct from apes was a popular one.)

Many commentators on the issue did not cast their vote with one side or the other, however. The possibility of tool-making apes must have seemed almost as objectionable as Miocene humans. Either way more evidence would be required before the competing hypotheses could be tested.

The opinions of Gaudry, Dawkins, Fiske, Wood, and others relied on the assumption that the flint shards and rib bone have been properly identified. Not everyone was sure this was so. In 1872 five scientists attending the Prehistoric Congress in Brussels examined them and could not find any sign that they have been made as tools. If this determination was correct then both sides were in error. As F.A. Seeley stated at a meeting of the Anthropological Society in 1883;

It is clear that neither to Prof. Dawkins and Prof. Gaudry, nor to their critic, is it hard to imagine that a creature, inferior to man both in physical and mental structure, may have made such progress in art as to be able to work so difficult a material as flint, and have developed such wants as to call for the practice of that art. If they do not mean this, their language is meaningless. There is no practical difference between their notions. Both lose sight of the nature of art and the laws of human progress, and both indicate a conception of art prior to man, but an inability to conceive of man as existing without a certain degree of progress in art.

Seeley rejected the hypotheses of his colleagues on the grounds of art and culture, but he may have been right for the wrong reasons. I have not been able to find a source that lays this debate entirely to rest but it appears that the "tools" and cut-marked bone were naturally made. They did not indicate an ancient intelligence. It is entirely possible that scholars made more out of them than was warranted.

Before concluding, however, I hasten to add that we now know nonhuman apes (particularly chimpanzees) to be quite capable of making and using tools. A paper published in PNAS in 2007 by one of my former professors and other scholars even indicates that chimpanzees have been using tools for over 4,300 years. Unfortunately materials used by apes for tools, like sticks and rocks, do not always make it into the geological record or can be identified, but we presently understand tool-wielding apes to be more than just speculation.