Divje Babe flute

The Divje Babe flute, also called tidldibab, is a cave bear femur pierced by spaced holes that was unearthed in 1995 during systematic archaeological excavations led by the Institute of Archaeology of the Research Centre of the Slovenian Academy of Sciences and Arts, at the Divje Babe I near Cerkno in northwestern Slovenia. It has been suggested that it was made by Neanderthals as a form of musical instrument, and became known as the Neanderthal flute. The artifact is on prominent public display in the National Museum of Slovenia in Ljubljana as a Neanderthal flute. As such, it would be the world's oldest known musical instrument.
This claim was met with severe criticism and dispute within the scientific community. There are no other known instances of a Neanderthal musical instrument, and such a find from the Middle Paleolithic might indicate previously unknown symbolic behavior among Neanderthals.

Site

The location of the site is a horizontal cave, long and up to wide; it is above the Idrijca River, near Cerkno, and is accessible to visitors. Researchers working at the site have uncovered more than 600 archaeological items in at least ten levels, including twenty hearths and the skeletal remains of cave bears. According to the museum's statements, the flute has been associated with the "end of the middle Pleistocene" and with Neanderthals, about 55,000 years ago.
The cave site's excavation was led by Mitja Brodar from 1978 to 1986, and again from 1989 to 1995 by Ivan Turk and Janez Dirjec.

Neanderthal flute

The bone was discovered in a 1995 expedition led by Ivan Turk. When it was found, he proposed that it was either a musical artifact or a gnawed bone pierced with teeth, favouring the former.
As described by Turk and his colleagues, the Neanderthal musical instrument from Divje babe I would be the oldest known musical instrument. He believes it is currently the strongest material evidence of Neanderthal musical behaviour. It is at least 10,000 years older than the earliest Aurignacian wind instruments discovered in the German caves Hohle Fels, Geißenklösterle and Vogelherd. The Neanderthal musical instrument is on display at the National Museum of Slovenia in Ljubljana.
Whether the artifact is actually a flute created by Neanderthals is the subject of debate, and many believe the holes in the bone are not of artificial origin. Archeologist Mitja Brodar, who worked at the site before Turk, was very skeptical that the bone was of Neanderthal origin. Many others have suggested it could have been produced by animals biting or chewing the bone, and consider a carnivore origin more likely.
The National Museum of Slovenia maintains that evidence presented by Turk in 2005 had "finally refuted hypotheses that the bone was perforated because of a bear bite". The manufacture by Neanderthals "is reliably proven" and its significance in the understanding of their capabilities and the development of music and speech is secure. An experimental [|reconstruction] by Ljuben Dimkaroski demonstrated that a plausible original shape of the bone can be used as a practical musical instrument.
The dating of the bone, the presence of Neanderthals at the site, as well as the presence of carnivorous animals, are generally agreed upon. The primary dispute is whether it is more likely to be a Neanderthal made flute, or simply the product of a carnivore's chewing. Debate focuses on the following three questions:

Were the holes produced by carnivore teeth?
Were the holes produced by tools?
Could the shape of the artifact occur from random chewing, or does it demonstrate musical function so well that it must have been designed?
Description

The artifact is an 11.4 cm long left diaphysis of femur that belonged to a one to two year old cave bear cub. On the posterior side, there are two complete holes in the central diaphysis. At both ends, the bone is broken, but there are two semicircular notches, one on each side of the two complete holes. On the anterior side, there is a semicircular notch in the broken end.
According to Turk, all the holes and notches are arranged in a line and have a similar morphology, except for the larger notch 4.
Proximally and distally to hole 3, a portion of the cortical bone is abraded. On this spot, a longitudinal fibrous bone structure is exposed. Near the proximal edge of hole 3, there are two parallel micro-scores on the abraded surface of the cortical bone.
Inside the medullary cavity from which the spongy bone was removed, the cortical bone is broken off at the edge of notch/hole 1, 2, 3, and 5. A funnel-shaped fracture of the inner edge of these holes is a typical damage occurring during piercing the cortical bone. Notch 4 does not have a funnel-shaped fracture inside the medullary cavity.
On the posterior side of the bone, a V-shaped fracture is present on the proximal end, reaching the nearest notch 1. On either side of this fracture is a partial straight sharp edge, presumed to be a mouthpiece by Turk.
A similar fracture is present on the anterior side of the distal end, reaching notch 5, which was presumed to be a thumb hole for the flute.

Context and dating of the flute

The Neanderthal flute was found in the Mousterian level, which contained lithic artefacts and hearths. The flute was cemented into the phosphate breccia in close proximity to the hearth. The Mousterian level containing the flute was below an Aurignacian level containing stone artefacts and osseous points of anatomically modern humans, separated by about 2 m of sediment. Remains of and evidence for many types of large mammals are present at the site as well, including many carnivores which could have interacted with the bone artifact.
Based on the radiocarbon dating of the charcoal found in the hearth, the age of the flute was initially estimated at 43,100 ± 700 years BP. Later dating using electron spin resonance has shown that the layer containing the flute was outside the accurate range of the radiocarbon method, and that the original dating of samples from this layer was incorrect. According to ESR dating, the age of the flute is now estimated at 50,000 to 60,000 years BP.

Argument for carnivore origin

Arguments have been made that the holes were possibly created by the teeth of an animal, chewing or gnawing on the bone, and that the resemblance to a flute is only coincidental.
Other known Upper Palaeolithic flutes made from the limb bones of mammals show clear traces of artificial creation of holes which were carved or drilled with stone tools. In flutes made from thin, delicate bird bones, the holes were made by grinding the bone cortex. The edges of the holes on the Neanderthal flute differs from those on Upper Palaeolithic flutes and shows no conventional signs of human manufacture. In addition, both ends of the Neanderthal flute show damage typical of gnawing by carnivores.

Francesco D'Errico made an analysis of the artifact in comparison to cave-bear bone accumulations where no hominid presence was known. After inspecting the artifact firsthand, D'Errico wrote that "the presence of two or possibly three perforations on the suggested flute cannot therefore be considered as evidence of human manufacture, as this is a common feature in the studied sample." Of one sample, D'Errico stated that a "femur of a young cave bear from the same site shows two holes very similar in size and shape to those on the supposed flute, recorded on the same face and in the same anatomical position."
Nowell and Chase published an analysis of the flute, stating "the specimen has very clearly been heavily gnawed by a carnivore", compared it to other well known specimens of similar bones, argued that notch 5 was likely created at the same time as hole 3 by the animal's opposing teeth, and that the heavy gnawing at both ends was evidence that the bone had not been cleared of marrow which would have been needed to play it as a flute. "This is a chewed bone, nothing about it is inconsistent with this as an explanation, and nothing about the bone is very surprising given that it was heavily chewed."
Gerd Albrecht et al. conducted experiments with bones and stone tools and concluded that "at this time there are no confirmed arguments for flutes made from bear bones, including the find from Divje Babe."
Ian Morley wrote, in a review of many prior publications, "it is most likely that the Divje babe I object as we see it today is the product of a number of stages carnivore activity, and there is no need to invoke any hominin agency in the creation of the object."
Cajus Diedrich suggested the holes could be explained by scavenging from spotted hyena.

Turk has published many articles rebutting the carnivore origin over the decades since the bone was found. In 2001, Turk's group made metal dental casts of cave bear, wolf and hyena dentition. The casts were used to pierce juvenile and adult fresh brown bear femurs. Several arguments were made:

Only the canine teeth of a bear were a suitable match, but because of the oval cross-section of a bear's tooth it would be awkward for the bear to have aligned this bone correctly to produce the holes in this orientation.
Holes pierced with canine teeth have smooth edges, whereas the edges of the holes on the Neanderthal flute are irregular and serrated.
It would be impossible for a carnivore to make two or more holes on the thickest and the rigid central part of the juvenile femur without breaking it.

Though he argues for Neanderthal origin of the artifact, Turk presumed that the V-fracture at the proximal end is a typical carnivore damage that occurred after the flute was no longer in use.

Argument for Neanderthal origin of the holes

Arguments have been made by Turk and colleagues that it is possible for this artifact to be produced with known Neanderthal tools.
Pointed stone tools appropriate for piercing bone were found in several Mousterian levels at Divje babe I. In addition, several ad hoc bone punches were found in Mousterian levels.

Turk believed that micro-scores near hole 3 suggested the cut marks of stone tools, indicating artificial modification of the cortical bone before hole 3 was made, thinning the cortical bone where it is the thickest to facilitate perforation of the femur.
Turk found broken tips, fractures and macroscopic damage presented on some pointed stone tools. Turk and colleagues found experimentally that the same type of damage occurs if one hits the stone tool with a wooden hammer when chiselling and piercing bone.
Using replicas of pointed stone tools, Giuliani Bastiani pierced bones with a previously undescribed method: he used the pointed stone tool simultaneously as a chisel and a punch, and succeeded in making holes in the fresh femur similar to those on the flute. The conclusion from this experiment was that the edge of the holes made in this way did not always show the characteristic cut marks left by a stone tool. However, the holes made by Bastiani did not have such pronounced funnel-shaped fractures around the inner edge, as found on the holes of the flute.
Following Bastiani's experiment, archaeologist Francois Zoltán Horusitzky used a pointed stone tool, first making a shallow pit in a fresh bone without piercing it, then inserted a bone punch into the pit and struck it with a wooden hammer to pierce the bone cortex. The holes made with this technique have a pronounced funnel-shaped fracture around the inner edge and showed no conventional tool marks.
Turk published a 2005 analysis of the specimen based on computed tomography, in which he concluded that "the two partially preserved holes were formerly created before the damage... or before the indisputable intervention of a carnivore."

Iain Morley was critical of Kunej and Turk's assessment, noting that despite the large number of bones discovered at the site, "only two other possible cases of human action... and the subject
femur is the only one of 600 cave bear femurs to carry any such possible traces of human action." He concluded that "the direct evidence for human agency is, at best, highly
ambiguous, and there is a lack of evidence of other possible human workmanship on the bone."