Chiquihuite cave facts for kids
Chiquihuite Cave is a possible Upper Paleolithic archaeological site in the Astillero Mountains, Zacatecas State, in North-Central Mexico. Chiquihuite Cave may be evidence of early human presence in the Western Hemisphere up to 33,000 years ago. It is located 2,740 meters (9000 feet) above sea level and about 1 kilometer higher than the valley below. The lithic artifacts discovered here have been dated to 26,000 years ago based on more than 50 samples of animal bone and charcoal found in association with the tools. There is scholarly debate over whether the artifacts should be considered evidence of human activity or if they were formed naturally.
Excavation history
Excavations were started in 2012, when a test pit unearthed unusual stone artifacts. Further excavations were carried out in an expanded 3-meter-deep excavation unit in 2016 and 2017 under the leadership of Dr. Ciprian Ardelean of the Autonomous University of Zacatecas (Mexico). Dr. Ardelean’s team recovered 1,930 stone artifacts from the Cave. Evidence of wind-blown sediment indicates that these artifacts could have moved horizontally, but not vertically through stratigraphic layers used to date them. The researchers obtained 46 radiocarbon dates from bone, charcoal, and sediment samples. They found six more dates using luminescence dating. The dates indicate that the artifacts were used and discarded about 26,000 years ago.
In addition to analyzing the stone artifacts, Dr. Ardelean’s team used pollen analysis and DNA extractions to find if early humans had been present in the Cave.
Evidence of early humans
Many of the artifacts found in Chiquihuite Cave are considered to be human tools. Almost 30 percent of the tools show signs of usage around the edges. They are made of black and green limestone. The use of limestone indicates human selectivity because of its availability near the Cave but not within it. The shape of many of the artifacts also suggest that they were flaked using human tools such as wooden or bone hammers. Dr. Ardelean considers some of the artifacts to be transversal points, suggesting that they were made using microlithic technology. This technology differentiates the artifacts from similar ones found at nearby sites.
Researchers also considered environmental data. They found palm phytoliths in all samples from inside the cave. It is unlikely that the palm phytoliths were naturally present in the Cave based on the high altitude. It is more likely that they are remnants of plants brought into the cave by early humans.
DNA from a wide range of animals was found in the cave, including black bears, rodents, bats, voles, and even kangaroo rats. DNA sequencing indicates that an ancestor of the American black bear was present in the cave 16,000 years ago and a now-extinct giant short-faced bear was in the cave 13,000 years ago. No human DNA was found. The chances of finding human DNA in the Cave were low, so human presence should not be ruled out because of this factor.
The site is lacking in cultural evidence of humans, making archaeologists conclude that the site was visited only occasionally by bands of hunter-gatherers; perhaps it was used as a refuge during particularly severe weather. Evidence indicates that the cave was in use for approximately 16,000 years. If that is correct, Chiquihuite Cave serves as significant evidence that humans were adapted to living in high altitude mountainous areas much earlier than previously thought.
Regional context
According to the scientists involved in this research, recent investigations have uncovered good evidence of a human presence during the Late Pleistocene and Early Holocene epochs in other parts of Mexico, too. They refer to “the northwest region of Mexico, the Chiapas Highlands, Central Mexico, and the Caribbean coast”. This new research pushes back “dates for human dispersal to the region possibly as early as 33,000–31,000 years ago”.
Other sites in the Western Hemisphere including Bluefish Caves in Canada and the Santa Elina shelter in Brazil (Abrigo de Santa Elina) have yielded similar dates to Chiquihuite. Transversal points similar to those found in Chiquihuite Cave are common at Pleistocene sites in South America including the Toca da Tira Peia, Toca da Pena (Serra da Capivara National Park), and Toca da Janela da Barra do Antonião-Norte sites in Brazil.
See also
In Spanish: Cueva del Chiquihuite para niños
