Cannibalism: A Perfectly Natural History(27)
But among anthropologists, even this type of evidence sparked a controversy.
In 2000, researchers working in the Four Corners region of the American Southwest reported that human myoglobin (a form of hemoglobin found in muscles) had been identified from a single fossilized coprolite described as being “consistent with human origin.” The petrified poop had evidently been deposited onto a cooking hearth belonging to prehistoric Puebloans (Anasazi) sometime around 1150 CE. Together with defleshed human bones and butchering tools coated with human blood residue, the 30-gram fecal fossil was used to support the claim that cannibalism had taken place at the southwestern Colorado site known as Cowboy Wash. It is a finding that has been the subject of considerable debate, with some researchers insisting that the bone and blood evidence could also have resulted from corpse mutilation, ritualized executions, or funerary practices.
These scientists also point out that while the myoglobin in the coprolite was certainly human in origin, the animal that produced the feces was never positively identified. This raises the possibility that a coyote or wolf consumed part of a corpse and subsequently defecated in the abandoned cooking hearth.
Even with a set of paleoanthropological safeguards in place, mistakes can still occur. Some of these have been the result of bad writing, while in other instances, further research led to the discovery of additional non-cannibalism-related alternatives, these having nothing to do with animal or human interactions.
“In many cases you’re finding bones in the normal paleontological environment,” Ian Tattersall explained. “That is to say, they’ve all been scattered and they’ve been concentrated by water or whatever’s happened to them, which had nothing to do with the actual human activities that may or may not have been carried out after they were deceased.”
To envision how this “scattering” or concentration of fossils can occur, picture a stream cutting through a fossil-containing layer of rock. As the stream walls gradually wear away, fossils are exposed, washed out, and deposited into the stream bed randomly and over time. Similarly, different parts from the same organism might be exposed at different times, which can also lead to fragments from a single individual being scattered across a wide area.
This water-assisted movement can also take place before the specimens are fossilized. For example, the bodies of creatures that died along the length of an ancient body of water—or in it—may have been carried away by currents and deposited together due to gravity or the physical properties of the stream or river. If sediments covered the bodies rapidly enough, they may have become fossilized, but their final location may have little or nothing to do with the behavior and associations that took place when the organisms were alive. For this reason, archaeologists must be cautious when animal and human bones are found mixed together. The mélange does not necessarily prove that humans did the mixing.13
One instance in which the evidence for human cannibalism remains solid involves Homo antecessor (“pioneering man”), the reputed ancestor of Neanderthals. The first fossils of this species were uncovered in the 1980s in Atapuerca, a region in northern Spain. Initially, spelunkers found the bones of extinct cave bears at the bottom of a narrow 50-foot-deep pit. Excavation of the pit, now known as Sima de los Huesos (Pit of the Bones), was initiated in 1984 by paleontologist Emiliano Aguirre. After his retirement, Aguirre’s students continued to work at the site, and in 1991 they began emerging from the stifling heat and claustrophobic conditions with well-preserved hominid bones.
Since then, the site has yielded more than 5,000 bone fragments from approximately 30 humans of varying age and sex. The researchers noted that some aspects of the skull and post-cranial skeleton appeared to be Neanderthal-like (including a large pelvis that someone christened “Elvis”). Eventually, though, the remains from Atapuerca exhibited sufficient anatomical differences from Neanderthals to warrant placing them into a separate species.
According to Ian Tattersall, Homo antecessor was “almost Neanderthal but not quite. . . . These guys were on the way to becoming Neanderthals.” To the surprise of researchers, the remains of Homo antecessor recovered from Sima de los Huesos were dated to a minimum of 530,000 years, indicating that the Neanderthal lineage had been in Europe 300,000 to 400,000 years before the first Neanderthals, far longer than anyone imagined.
By 1994, researchers were claiming that Homo antecessor remains showed evidence of having been cannibalized. In this case, the fracture patterns, cut marks, and “tool-induced surface modification” were identical to the damage found on the bones of non-human animals that had presumably been used as food. All of the bones (human and non-human) were randomly dispersed as well. The researchers at Atapuerca concluded that the H. antecessor remains came from “the victims of other humans who brought bodies to the site, ate their flesh, broke their bones, and extracted the marrow, in the same way they were feeding on the [animals] also preserved in the stratum.”
Interestingly, the presence of so many types of game animals led the same researchers to suggest that Atapuerca did not represent an example of stress-related survival cannibalism, and Tattersall agreed. “Sometimes the environment was pretty rich and you wouldn’t necessarily need to practice cannibalism to make your metabolic ends meet, as it were. You’d be able to relatively easily find sources of protein otherwise.”
Accordingly, the Neanderthal ancestors living at Atapuerca were likely not prehistoric versions of the Donner Party—stranded in horrible conditions and compelled by starvation to consume their dead. Instead, Homo antecessor, like many species throughout the animal kingdom, may have simply considered others of their kind to be food. In other words, they may have eaten human flesh because it was readily available and because they liked it.