Graham Hancock Claims Los Angeles Fossils Are Linked to Younger Dryas Comet

​In a month’s time, Graham Hancock will release his new book, America Before, which attempts to document what he claims to be evidence for a lost civilization that was destroyed when a comet collided with North America at the start of the Younger Dryas period about 12,900 years ago and triggered horrific wildfires that burned much of the continent. Skeptic magazine has commissioned me to review the book, and my review will be published when the book is released in the United States in April. But in the meantime, Hancock tweeted what he said was supporting evidence that his comet holocaust killed off the megafauna of Ice Age America:

The dates & evidence of exposure to wildfires link this to the Younger Dryas comet impacts that devastated North America around 12,900 years ago.Not only the megafauna went extinct then. We also lost an advanced civilization from the record. https://t.co/kJqoDISfWq

— Graham Hancock (@Graham__Hancock) March 6, 2019

​The article Hancock cites describes the discovery of a trove of Ice Age mammal fossils in excavations being done in Los Angeles for a new branch of the city’s subway. One set of sloth bones was found alongside pieces of charcoal, which investigators suggest represented the remains of a wildfire that caused the mudslide that killed an buried the animals. Their analysis, however, does not support the claim that this wildfire was the world-ending apocalypse envisioned by Younger Dryas comet impact believers, even though the fossils date to 12,900 years ago, the same time frame as the alleged impact:

​John Harris, who leads Cogstone’s laboratory work identifying fossils, said in an interview that partial sloth skeleton was discovered in sediments that contained fragments of charcoal, indicating the beast was preserved in a mudslide that likely resulted from an ancient wildfire.
 
“Like today, there’s a wildfire followed by rains which spark a mudflow,” Harris said. “As the mudflows capture people and cars today, they also caught bison and sloths before.”

​There is, of course, no evidence to link the particular wildfire described here to the supposed Younger Dryas comet-induced fires that allegedly burned over the whole globe. I’ll note, though, that the fragments of charcoal don’t match the “carbon-rich black layer” of iridium, charcoal, soot, carbon, and nanodiamonds that Younger Dryas comet researchers claim represents the remains of these global wildfires. They also claimed that the bones of megafauna were not found in the soot layer, unlike the sloth found mixed up with mud and charcoal. “The in situ bones of extinct Pleistocene megafauna, along with Clovis tool assemblages, occur below this black layer but not within or above it,” R. B. Firestone et al. wrote in 2007.
 
By coincidence, the current issue of Skeptical Inquirer contains and article challenging the Younger Dryas impact hypothesis that addresses the issue of the conflagration. Impact physicist Mark Boslough wrote that “the swarm-of-descending-fireballs idea was based on a less-than-accurate TV documentary animation of a simulation I had done to test an idea that I had long since rejected.” He takes issue with a number of comet impact claims, but regardless of whether a comet hit, the existence (or non-existence) of the comet implies nothing about the existence of Atlantis any more than it would unicorns or leprechauns.
 
It remains a point of astonishment that the bones of megafauna that supposedly died in the comet strike turn up with regularity, but every human being and all of the buildings, tools, and material possessions of the lost Atlantis-like civilization were blasted clean off the face of the Earth, without a single trace remaining. I have trouble imagining that a sloth can manage to have its bones preserved for all time, but not a single outpost of Atlantis had even a single bolt or screw remain.