Scientists recently found the residue of Chilean palm fruit (Jubaea chilensis) on gomphothere (Notiomastodon platensis) teeth. This species was closely related to mastodons, and I referred to it as a mastodon in last week’s blog entry. This evidence supports a hypothesis first proposed 44 years ago by Dan Jansen and Paul Martin. They hypothesized many species of tropical plants that produce large fruits and seeds are anachronisms and have limited distributions today because the megafauna that spread their seeds in their dung became extinct about 11,000 years ago. The scientists who published this study looked at 96 gomphothere teeth. Over half of the specimens came from Lake Tagua Tagua, a glacial lake located in Chile. The cold waters of Lake Tagua Tagua preserve evidence dating to the Pleistocene. In addition to remains of gomphotheres, scientists have recovered the bones of horses, llamas, deer, ground sloths, waterfowl, frogs, and fish; all dating to the Pleistocene. They’ve discovered archaeological evidence here as well including a possible hearth, stone scrapers, and bones of horses, deer, and gomphotheres apparently butchered by humans. This archaeological evidence dates to 12,500 years ago.

Location of Lake Tagua Tagua where evidence of extinct megafauna has been found. Image from the below referenced study by Gonzales-Guardia et. al.

Lake Tagua Tagua is a beautiful glacial lake and for people who like to travel might be a real nice place to visit.

Gomphotheres ate Chilean palm fruit and spread the seeds across the landscape in piles of nutritious manure. While preparing this article, AI spell check informed me that I have been spelling the word gomphothere wrong for 16 years. I never noticed the h next to the p. No reader ever pointed this out either.

Lone Chilean palm. They were more common and widespread when gomphotheres existed.

Chilean palm fruit. Reportedly, the fruit is mediocre but the seeds taste like coconut.

Monkey puzzle tree, another anachronistic species that depended upon megafauna for distribution.

Monkey puzzle nuts look like pine nuts, but they need to be processed before humans can eat them.

Gomortega trees have a limited distribution today because of the Pleistocene megafauna extinction.

Gomortega fruit. People make a marmalade out of this fruit.
Chilean palm produces a fruit and a nut. Reportedly, the fruit is tasteless, but the seed has a delicious coconut-like flavor. People make wine from the palm sap. 2 other species of plants found in Chile produce fruits that gomphotheres likely ate and spread in their dung–monkey puzzle trees (Araucaria araucana) and gomortegas (Gomortega keule). Monkey puzzle trees produce pine nuts edible for humans but need to be processed before consumption. Gomortegas produce a fruit used to make marmalade.
The scientists who published this study used a statistical analysis to determine 40% of the tropical plants that depended upon megafauna for dispersal are threatened compared to just 10% of other tropical species. Rodents, birds, monkeys, and tapirs can spread some fruits but are not as effective as extinct megafauna. Some of them consume the actual seeds, thus preventing germination.
References:
Gonzalez-Gaurdia, F.; et al
“Fossil Evidence of Proboscidean Frugivory, and its Lasting Impact on South American Ecosystems”
Nature Ecology and Evolution June 2025
Labarca, R.; et al
“TaguaTagua 3: A New Late Pleistocene Settlement in a Highly Suitable Lacustrine Environment in Central Chile (34 degrees S)”
PLOS ONE 19 (5) May 2024


























































