Cactus Hill facts for kids

Cactus Hill is an important archaeological site in southeastern Virginia, United States. It's located on sand dunes next to the Nottoway River, about 45 miles south of Richmond. The site gets its name from the prickly pear cacti that grow a lot in the sandy soil there.

Cactus Hill might be one of the oldest archaeological sites in North and South America. If scientists can prove that people lived there 16,000 to 20,000 years ago, it would show that humans were in the Americas even before the well-known Clovis people. The site has different layers showing human activity from various ancient times. Two of these layers show activity from very early Paleoindian times.

Why Cactus Hill is Important

Some archaeologists, like Dennis Stanford and Joseph and Lynn McAvoy, believe Cactus Hill proves that people lived in North America before the Clovis culture. This is a big deal because it challenges older ideas about how the first people arrived in the Americas.

For a long time, many scientists believed in the "Clovis first" idea. This idea said that the Clovis people were the first widespread group to live in the Americas. This belief became popular in 1933 after a flint spearhead was found at Clovis, New Mexico. A mammoth skeleton was found next to it, and it was about 11,500 years old. At that time, this was the oldest sign of humans in the Americas. People thought that the special Clovis point spearheads appeared at the same time as large animals like mammoths disappeared. It was also believed that these people came from Siberia, crossing a land bridge called Beringia. This land bridge appeared when sea levels were low during the Ice Age, allowing people to cross between 14,500 and 14,000 years ago.

However, the discoveries at Cactus Hill in the mid-1990s made scientists rethink the "Clovis first" idea. New evidence started to suggest that humans were here before the Clovis culture. A 2008 study of DNA suggested that the first people came to the Americas in a more complex way. It showed that a group of people from Asia stayed in Beringia during the last Ice Age, between 23,000 and 19,000 years ago. Then, this group grew quickly and spread out between 18,000 and 15,000 years ago. These findings support the idea that people were in the Americas before the Clovis culture. They might have settled the continent quickly by traveling along the Pacific coast in boats. Another site, Page-Ladson in Florida, has also shown signs of pre-Clovis people.

What Was Found

At Cactus Hill, there are several inches of sand between the Clovis-era layer and an even older layer below it. This lower layer, which is from a time before the Clovis culture, includes:

• Two spear points. Small marks on these points show they were attached to handles. Broken tips suggest they were used as projectiles and broke when they hit something.
• Blades. Marks on these blades show they were also attached to handles and used for cutting meat and processing animal hides.
• High levels of phosphates. This usually means that humans lived in that area.
• Many plant remains called phytoliths. These were studied and found to be from burned hickory wood.
• 20 pieces of animal remains. These included ten turtle shell pieces, two deer toe bone pieces, and five fossil shark's teeth.

How We Know the Site is Real

Some researchers questioned the Cactus Hill site because it's on a sand hill. Sandy ground can sometimes mix up layers, making it hard to tell how old things really are.

However, scientists have done many tests to confirm the site's integrity.

• James C. Baker from Virginia Tech studied the soil. He found that the site was made of sand blown by the wind.
• James Feathers from the University of Washington confirmed that the buried sand layers had not been disturbed by later deposits.
• Lucinda McWeeney from Yale University found charred plant remains. She saw a connection between the stone tools and the plants used at the site. This connection shows that the human activity layers at the site have not been mixed up.
• Dr. Carol Mandryk from Harvard University did tests that supported the idea that the 15,000-year-old layer was mostly undisturbed.
• Richard I. Macphail and Joseph M. McAvoy also studied the layers very closely. They found that sand dunes formed, then brief layers of fine soil appeared where humans lived and left tools and charcoal. Animals also helped mix some fine soil into the sand.

Overall, these studies suggest that the layers at Cactus Hill are mostly intact. This means the site is a reliable place to learn about very early human life in the Americas.