Karl Ammann, a Swiss wildlife photographer, has been searching for the mystery ape of Bondo. His page on The Bondo Mystery Ape starts with the Economist article on his efforts:
A hundred years ago, on October 17th 1902, Oscar von Beringe, a German explorer, ‘suddenly noticed a troupe of large black monkeys’ while climbing a volcano in eastern Congo. ‘We were able to shoot two of these monkeys,’ he wrote, ‘which hurtled down the gorge of the crater with an incredible rumble.’ That von Beringe then found himself ‘unable to classify the monkey’ is not surprising. He was the first European to come into contact with a mountain gorilla.
Gorillas, mountain and otherwise, are rare now. Poachers kill the adults for their meat, and sometimes to make knick-knacks for foreigners. Youngsters are taken from the wild to adorn private zoos. But even after a century, that diminished population may yet hold a surprise.
In 1908 two apes were shot near a place called Bondo, in northern Congo. Their skulls (and two others found in local dwellings) had the crests characteristic of gorillas, but they were unusual enough for taxonomists of the time to classify them as a separate subspecies. Since then, no further specimens of this subspecies have been recorded. Four years ago, Karl Amman, a Swiss wildlife photographer, took up the quest to rediscover the missing gorillas. What he has found is not yet clear. But it might just be a new species of ape.
Mr Amman’s expeditions into the forest of Bili, near Bondo (the latest of which, accompanied by this correspondent, has just returned from the bush) have not seen a live ape. But they have found a lot of ground nests. Such nests are characteristic of gorillas. Chimpanzees, the other species of ape that lives in this area, prefer to sleep in trees. Other spoor point to the presence of gorillas, too. Feces in the area resemble those of gorillas, as does the way that saplings are broken down around nest sites. As if to clinch it, Mr Amman has also found another crested skull lying around.
Some of the nests, however, have hairs in them. And hairs contain DNA. That yielded a surprise. The DNA looks like that of a chimpanzee, not a gorilla. Moreover, a re-interpretation of the skull Mr Amman found has pronounced it to be that of a chimp, albeit a crested one. And analysis of the feces suggests that whatever dropped them was eating a fruit-rich diet. That is also characteristic of chimps. What Mr Amman seems to have found is a chimpanzee that behaves like a gorilla.
Local hunters’ reports point to something unusual, too. Bondo’s hunters do not distinguish between gorillas and chimpanzees. Instead, they divide the local apes into “tree-beaters” and “lion-killers.” These two types look the same, and both flee hunters. But lion-killers, say the hunters of Bili, are much bigger and are difficult to kill, even with a poisoned arrow. Several enormous chimp footprints seem to confirm the hunters’ reports of an out-sized chimp. And, in a photograph recently obtained from a hunter, the body of one chimp appears to be about 1.8 metres tall (five feet or so). Indeed, to nest confidently on the ground in forest thick with lions and leopards, the lion-killers would probably have to be of such a size.
Whether such lion-killers really are a distinct population, corresponding to Mr Amman’s ground-nesting “chimpanzees” and whether they are so different from other great apes that they constitute a separate species, remains to be seen. But it is surprising that in the early years of the 21st century such a discovery could even be contemplated. Apparently, the jungle has not given up all its secrets yet.
Ammann makes some interesting comments:
In 1898 a Belgian officer returning from the Congo provided the Trevuren Museum in Bruxelles with three gorilla skulls which he had collected near Bondo in Northern Congo and a village further south near the Itumbiri River.
This Bondo location is about half way between the extreme edges of the Western and Eastern distribution of any gorilla populations.
In 1937 based on the skulls anatomical differences and their unique origin Henri Schouteden named an new subspecies: Gorilla Gorilla uellensis.
I did a first survey of the forests around Bondo in 1996 returning with a skull which had a pronounced sagittal crest (as male gorillas do). However all the rest of the measurements associated with the skull were those of a chimpanzee.
In the subsequent years the war situation in most of the Congo made travel to the Bili/Bondo area very difficult. I recruited a Cameroonian bush meat hunter to visit and survey the area. This guy had killed dozens of chimpanzees and gorillas in his life and would be able to assess any tracks he would find.
The local population told tales of large and normal chimps. The normal ones could be hunted with the poisoned arrows when feeding in trees, the big ones however hardly climbed trees and would not succumb to the poison fast enough before fleeing and getting lost in the forests. The Azande translation for names used for apes include: The ones which beat the tree! and The one which kills the lion.
Early mitochondrial DNA tests point to the same conclusion:”The ground nesting chimps are clearly of the schweinfurthii subspecies.” (He presents a phylogenetic tree.) I enjoyed the quoted morphologist’s take on genetic analysis:
There is a general misunderstanding about genetics including by those that are working with it. Genetic analysis is not presently a very accurate method for determining relationships of populations. Moreover it is long, labrious and costly and necessitates a large sample to make any sense of it.