In one of my earlier incarnations, I very much wanted to study the origins of homo sapiens on Earth. I was extremely interested in archaeology, with an emphasis on paleo archaeology and anthropology. My heroes were people like the Leakey family, Donald Johanson (discover of the hominid known as "Lucy"), and Leakey proteges like Diane Fosse and Jane Goodall.
At some point, I shifted my emphasis to the paleo history of the Americas and read everything I could find about it. At the time I first became interested, the conventional wisdom was - and, in fact, for a long time continued to be - that humans first set foot on these continents via a bridge from Asia that existed across the Bering Straits around 13,000 to 11,000 years ago. They were designated as the Clovis people based on distinctive spearheads that were found among mammoth bones near Clovis, New Mexico.
Those spearheads were found in the 1930s and the theory that arose from them held sway in the archeological community for decades, More recently, however, technology has improved the ability of archaeologists to study sites and find artifacts, plus there have been a lot more people looking and interpreting what they find. Cracks began to appear in the edifice built by the Clovis theorizers.
And now, discoveries made in a sinkhole in the Aucilla River, south of Tallahassee, may have dealt the lethal blow that will bring the whole structure tumbling down.
The artifacts discovered so far include a stone knife, mastodon bones, and fossilized dung, and scientists are able to deduce from them that humans lived in the northern regions of what is now Florida at least 14,500 years ago. These humans butchered or scavenged the mastodon at the sinkhole which at that time was a shallow pond that was a watering hole for humans, mastodons, bison, bears, and dogs. (It's unclear if the dogs were with the humans or were competitors for scraps.)
Where did those humans come from? How did they get to Florida? Did they cross all the way west to east across the continent to get there? Or did they arrive from some other direction? By water? Overland?
However they managed to get there, it must have taken a while, all of which argues for a much earlier pre-Clovis date for humans in the Americas. They must have been there before the 14,500 date of the artifacts recovered. The sinkhole is presently the earliest documented site for humans in the southeastern United States. Until the next discovery.
A new theory postulates that the ancestors of these humans may have entered the Americas by boat along the Pacific Coast. They could have traveled by boat to Central Mexico and then crossed the continent by traveling along the Gulf Coast all the way to Florida.
Using that reasoning, they might have crossd my yard some 15,000 years ago. Now, I like that idea!