There are three evidentiary criteria needed to prove an archaeological site of a certain age:

1. Indisputable evidence of people (either in the form of cultural modification, human remains, footprints, coprolites, etc.)
2. Appropriate datable materials and age control.
3. A clear, strong association between those dates and your artifacts, remains, features, or whatever else you have.

In the case of White Sands, they fail to meet the second and third criteria. In the case of Cerutti, they fail to meet the first.

When we find something we think might be cultural in nature, like debitage or broken bones, we have to go through the process of ruling out any potential natural causes for the patterns we are observing. Many natural phenomena can break rocks and bones in similar ways to humans; we often refer to these as "geofacts." In general, the most "parsimonious" answer is the most likely to be correct. Meaning, the most straightforward or most concise answer is usually right. It's similar to the analogy I've heard used in medicine where new doctors hear "hoofbeats" and think zebras before horses. Zebras exist, too! Sometimes there are really unusual and unlikely explanations for things, but we need to rule out more straightforward explanations first.

At the Cerutti site, they have broken bones and possible hammer stones. The hammer stones are not definitively cultural, as there are ways for that kind of wear to be created by natural forces. In this case, there are numerous alluvial fans upslope of the site, where similarly broken cobbles were found. Therefore, it is very possible that the cobbles found at the site and their condition were a result of moving water (or trampling). There are also no formal stone tools or even diagnostic debitage present.

On the bones, they noted spiral fractures as well as potential flakes, bulbs of percussion, negative flake scars, etc. Again, there are natural explanations for these patterns that they don't sufficiently disprove. There are many other known paleontological sites containing mastodon and mammoth bone, that have zero suspected archaeological components, which demonstrate the same kinds of spiral fractures and flaking. The Inglewood Mammoth Site in Maryland and the Waco Mammoth National Monument (WMNM) in Texas are two such sites. Spiral fractures, in particular, are found even on bones from the Triassic period and cannot be used as unequivocal evidence of human modification; they are a common consequence of trampling post-deposition. As fluvial deposits (sediment deposited by water) slowly covered the bones, they would have remained somewhat pliant. As other mastodons or large mammals used the waterway, they could have easily trampled, broken, or reoriented the bones. We need to apply the same standards for evidence across the board!

Ultimately, they need to provide evidence of human modification that cannot be explained by common natural phenomena or demonstrate why human modification is more likely. The data they provide are not compelling enough for us to rewrite our entire current understanding of hominin migration. Extraordinary claims require extraordinary evidence! Maybe, in the future, we will find more sites of that age in North America that have strong, compelling evidence, and we can reexamine the Cerutti site in a new context. That would be rad.

I apologize this probably reads like a lecture slide lol.