Ask any scientists what gets people all riled up within their field of expertise and you will get plenty of answers. Outsiders may think that these individuals, who are scientists and are supposed to be logical and even minded about things, have gone bonkers. Yet that is the way things are in many areas of scientific endeavor.

Take for example the hot button topic within the field of archaeology concerned with dating the arrival of the first human beings in the Americas. Some have argued that this interest, going back many generations, is, in fact part of a “Seventy year itch” within the field of archaeology.

So let’s see what this is all about.

photo credit: mitchgibis

There are many fascinating aspects related to the peopling of the New World, some of which I intend to write about in future contributions, but one of these is undoubtedly the most contentious of all: when did people arrive? In an earlier blog (Beyond Clovis) I wrote about the “Clovis First” school of thought and those who accepted Pre-Clovis human presence in the Americas.

As outlined in this earlier blog, most of the evidence pointing to human presence pre-dating the so-called Clovis people pushes the boundaries back by perhaps one thousand years. While that is certainly nothing to sneeze at, what would you say to those who are proposing to push the arrival of humans in the Americas back to 40,000 years ago, almost 30,000 years earlier than Clovis? Now there is something to chew on.

photo credit: BradWright79

Reports coming out of Central Mexico over the last few years have referred to fossilized footprints preserved in volcanic ash in that region. The research team that made the initial discovery in 2003 was led by Silvia Gonzalez who works at the John Moores University (JMU), in Liverpool. That year she was visiting a site at Cerro Toluquilla in the Valsequillo Basin, located near Puebla, about 100km southeast of Mexico City.

What caught people’s attention was the date associated with these footprints: they were said to be 40,000 years old.

Such a notion of great antiquity has ensured great attendance at scientific meetings. If this early date is accepted, it will blow the “Clovis First” hypothesis clean out of the water. However, when these findings were first published, the dates were dismissed as improbable and wrong, going back instead to no less than 1.3 million years ago. Some even suggested that the footprints were not, in fact, footprints, but pure geological phenomena that just happened to look like a footprint. This is where things remained for a few years, at least to outsiders. I am sure that the researchers involved in the project remained intensely interested in the dates and whether or not we were looking at real human footprints or else just tricks Mother Nature had up her sleeve for us. 

Researchers have now reaffirmed the originally suggested date of 40,000 years. This is the equivalent of throwing another big rock in the pond of Paleoindian archaeology. I am sure there will be pushback again and we will see where this ends up.

I have a feeling however, that these footprints could be a turning point in the field of Paleoindian studies. If the dates hold up, then scientists have a whole lot more questions to address. Such a development would also prove the way in which science moves: for every answer we find, ten new questions pop up.

Exciting stuff.