BY MATT MIHLBACHLER
One could say that the main goal of the Aucilla River Prehistory Project is romantic excitement. The search for Florida's first people is certainly one of the most special scientific endeavors currently taking place within the region. In the study of the past, the search for the oldest or the first of anything can be among the most exciting aspects of field work. Discoveries of this sort are of the kind that make major headlines. On the flip side of the coin, the Aucilla River Project has revealed a first of another sort. This first is certainly not glamorous nor romantic, yet for the paleontology enthusiast and for the scientific community it remains overwhelmingly exciting. This discovery consists of literally tons of mastodon digesta. To be more blunt, lying on the bottom of the Aucilla are loads and loads of dung from extinct elephants.
In case you are wondering just what mastodon digesta looks like, it consists of abundant little sticks and small chunks of bark, with an occasional seed here and there (see Figure 1 for a comparative specimen of modern African elephant dung.) It seems to be concentrated within the deepest portions of the Aucilla river. Matt Mihlbachler These deep areas are sinkholes that at one time served as watering holes for the huge beasts during drier portions of the year in the late Pleistocene. The digesta was laid down rapidly by these creatures as they relieved themselves while drinking from the water hole or even wading in it as modern elephants do today in Africa. Elephants produce a lot of waste, and presumably, so would a mastodon. This fact is largely responsible for the unique preservation of this material. The rapidity at which the dung layer was built up and compacted quickly isolated the lower layers from any exposure to oxygen, thus giving us beautifully preserved plant remains eaten by the mastodon.
So far, two sites have revealed the presence of this wonderful material. Latvis/Simpson contains mastodon dung that dates to at least 30,000 years old, prior to human occupation in Florida. The Page/Ladson site has gifted us with much younger dung dating to at least 12,000 years old, a time when people did inhabit Florida. You might think of this as a reasure chest full of gold because it gives us new insight into the interactions of Paleoindians and the now extinct Pleistocene megafauna.
Strangely enough, the mastodon digesta has traveled all the way to Carbondale, Illinois at the Southern Illinois University. It was brought to this unlikely destination by Lee Newsom, a University of Florida graduate and archaeobotanical specialist for the Aucilla Project, who now acts as curator for the Southern Illinois University Archaeology program. Fortunately, at this point, I was able to become involved with this work.
It is not surprising that there is no standard procedure for the analysis of mastodon digesta. Certainly the only way that we know to go about this process is by tediously picking through countless thousands and maybe even millions of individual plant fragments, sorting out whatever seeds and other identifiable plant remains can be found. The material is then identified, counted and recorded. Individual sticks and bark fragments are measured and drawn. Also, we have looked at how the sticks have been broken to determine if and how they have been bitten off and chewed by the proboscideans.
The waste products of an animal can reveal a potpourri of otherwise unavailable in formation about extinct animals.
1. Most importantly we now have a way of interpreting the exact diet of the Florida mastodon, which consisted of many browse plants including cypress, wild grape, buttonbush, willow, pine, pokeweed, mexican poppy, and wild gourd seeds.
2. Wild gourd seeds were found in the digesta. This is very interesting because most scientists previously believed that the gourd was first domesticated in Mexico and gradually reached Florida through the hands of Indians. We now know that this is too simplistic. Gourds reached Florida at least 30,000 years ago and were here before the arrival of Florida's first people. Indians in the eastern United States may have independently domesticated gourds, most likely without the outside influence of others.
3. The fact that some of the seeds recovered are dry land species that could not exist near the watering hole tells us a substantial amount about the ranging behavior of mastodons. They probably went on feeding sprees lasting for possibly up to two or three days, ranging far from the water source as the food supply was diminished in an ever growing ring centered around the watering hole during the driest months of the year. This tells us that the waterhole was one of a few limited areas for large animals to come and satisfy their thirst during dry season "starvation periods" of the Florida Pleistocene.
Stay tuned for more enlightening information derived from the mastodon dung research. We are continuing research on the digesta and are continually finding new things to learn from it. Some topics planned for the future are an examination of the preferences for different species of tree bark by mastodons. Like elephants, mastodons could have debarked, stripped, and knocked over trees, thus creating a substantial impact on the environment. The digesta can provide valuable information on the behavior and ecology of the Florida mastodon. We hope to discover ways to examine the chewing process exhibited by mastodon teeth and to differentiate between vegetation chewed by young and old mastodons. Another interesting avenue of research would be to compare the population dynamics before and after the presence of native Americans in Florida.