Morrow County Mastodon Site May Yield Rare Evidence of Paleo-Indian Involvement

Big mastodon bones being uncovered last Saturday, observed by Dr. Brush.  (Photo by Don Comis)

For a change, there were too many volunteers last Saturday, but it was a productive day with finding of possible flint tools near bones with possible cut marks, changing the dig's working hypothesis to a Paleo-Indian mastodon kill and/or butchering site.  (Photo by Don Comis)

In his September 24 e-mail report on the results of the Cedar Creek Mastodon site excavation in Morrow County, Ohio, on September 20, Ashland University’s Dr. Nigel Brush said, “The discovery of clusters of bones in association with some large flint flakes last Saturday, as well as possible cut marks on one of the bones…”  leads to “our present working hypothesis… that this site may be a Paleoindian [Also spelled "Paleo-Indian"] kill and/or butchery site.  This changes the goal of our excavation.  Instead of   trying to recover large bones from the mastodon skeleton, we will primarily focus on recovering evidence to validate our hypothesis that this is a human kill/butchery site.  Many mastodon sites have been found in Ohio and surrounding states, but only a few have good evidence for human interaction.   Therefore, we must change our excavation methodology….Our site has the potential to be rather significant, if we follow proper scientific procedures and are careful in our work.”

The changes include:

·         “Since we want to show the association between bones and possible flint tools, we must leave the bones and flint flakes/tools in place when we find them in undisturbed soils…” ;

·         Not touching flint flakes or tools “since we will be sending these off for blood residue analysis and oils on your skin may negate the analysis…”;

·         “Since we will be looking for additional cut marks on the bone, we must be very careful not to scratch the bones when exposing them.”

·         “Floors of excavation units must be kept flat so we can see what materials are in association at each level. Take each 10 cm level down in 5 cm (2 inch) stages.  In other words, take the whole unit down 5 cm. see what is showing up and record if necessary, then go down the other 5 cm.”

·         “…the final removal of bones, flint flakes/tools, and charcoal samples from excavated levels” will be supervised “to insure that they are properly handled, labeled, and stored.  Materials removed from these assemblages will be stored in separate containers from the regular excavation and screening bags…”.

The reason for these changes is that the new working hypothesis makes it important to document what materials are found near each other, as evidence they are related.   Flint flakes or tools  found near bones can be evidence that Paleo-Indians killed the mastodon at this spot and/or butchered it there.   Charcoal nearby could indicate a fire built by the Paleo-Indian hunters.

Paleo-Indians are prehistoric Native Americans that are generally thought to have arrived in North America from Asia at the end of the last Ice Age by crossing a vast ice and land bridge over the Bering Strait.   They were in Ohio during the time the mastodon being excavated probably died, about 13,000 years ago.  Some have blamed these hunters and a warmer climate for the extinction of mastodons.

Dr. Brush also said that, “When we first began excavating this site, we thought most of the mastodon skeleton might remain undisturbed, except for the damage caused by the backhoe during the digging of the drainage ditch.  That scenario is now much less likely since we are recovering fragmented mastodon bones from various parts of the body.  The skeleton could have become disarticulated by the activities of Ice Age predators, or by human hunters. “

But the discovery last Saturday of the large flint flakes near bones with possible cut marks led him to focus on the human hunters, at least for now.

"Discovering the Ice Age" Students Volunteer

Last Saturday’s excavation was in the fourth week of the mastodon dig and we had 62 volunteers, including 8 students from Dr. Brush’s  “Discovering the Ice Age” class, 12 students from Ashland’s  Geology Club and the club advisor, and 7 students from the University of Toledo. 

There were so many volunteers that I couldn’t find a spot to dig so I ended up sifting dirt all day, which was fine with me.  I shared a sifting screen with two novice students and another novice, the wife of an experienced volunteer.

Boy, did I feel great after finding two small pieces of the mastodon’s ivory tusk, before the other volunteers joined me.  I had learned the previous week to identify bones.  This week I learned to identify many tusk pieces because they tend to look like part of a wooden matchstick.

I had brought one to an experienced volunteer and he identified it as a piece of tusk.  When I found a similar piece I identified it as a piece of tusk.  It made me feel like an expert.  And when the complete novices joined me, they were asking me to confirm "bone or no bone" on their finds.  Soon they were finding bone after bone as well.  It was probably because the soil we were sifting had a lot of bone fragments, but it felt nice for them to say I was a good teacher when I complimented them on their finds.

A 300-million-year-old brachiopod fossil was a mere distraction during the mastodon excavation last Saturday.  (Photo by Don Comis)

  

One found a fossil and took it to her geology club advisor and he identified it as a 300-million-year old brachiopod.  It was exciting for us but of no interest to the mastodon diggers because they are only looking for bones or other things are about 13,000 years old, about the time the mastodon lived.

More big bones were emerging in Unit 14, which has been excavated to the 12- to 16-inch depth.  A new set of bones could be a wrist of the mastodon, but it hasn’t been completely unearthed yet.

The work continues this Saturday, September 27, but I’ll probably miss it because I had an earlier commitment to collect prairie seed at Guy Denny’s prairie in Fredericktown.

As a sidenote, Dr. Brush added that the University of Michigan has developed a 3-D image of a mastodon that we can use to identify the bones as we find them .  It can be seen here.   It is great, allowing you to rotate the skeleton in any direction, including upside down to see inside the rib cage. And  by clicking just right on a particular bone, you can examine the actual bone close-up and rotate it too!

The story behind the creation of this image by using new technology and scanned images of mastodon bones in the collection of the University’s  Museum of Paleontology is here.  It includes a nice video.

Dr. Brush also said that Brian Redman from the Cleveland Museum of Natural History will be visiting the site on Saturday, as well as a reporter from the Columbus Dispatch.

Note:  I'll try to add more of last Saturday's photographs to my "Mastodon Dig" slideshow on my website.

Closing in on a Mastodon

Ashland University and College of Wooster students make up a substantial portion of the volunteers on the Morrow County, Ohio, mastodon dig that began on August 23, 2014.  Photo, taken during lunch break on August 30, shows trench dug  to locate the path of the backhoe that first exposed mastodon remains. Plots are marked by string, with teams of four removing and examining soil, one 10-centimeter- deep layer at a time   (Photo by Don Comis)

Mastodon teeth.   (Photo of teeth from an unrelated dig,; photo found online, in public domain.)

After the second Saturday (August 30) of the Morrow County mastodon archaeological dig, co-leader Dr. Nigel Brush, said, “We believe that we are closing in on our quarry.”

He reported that on this second day—the first day I began participating in the dig—“We continued to find even more bone fragments, tusk fragments, and part of another tooth (in Unit 15).  Much of the bone is coming from disturbed soil in Unit 15.  The two teeth that have been recovered so far are from Unit 5.  Therefore, it is beginning to look like these two units are at the heart of the site.  For the past two weeks we have been focusing our efforts on Units 4-6 and 14-16, because this is where most of the surface scatter of broken bones and tusks was concentrated.

“However,” Dr. Brush, associate professor of geology at Ashland University, continued in an e-mail report, “we are beginning to wonder how much of the skeleton has been damaged.  It appears that most of U-15 has been disturbed.  This is why we cut such a long, deep cross trench through this unit before the excavation began - we were looking for the disturbed soil of the drainage ditch, but we found disturbed soil throughout most of the unit.  We were in hopes that the damage to the skeleton was confined to a 12-inch wide cut made by the backhoe.  Unfortunately, the disturbance seems to be more widespread than this.  By taking these units down in 10 cm. levels, we hope to better understand the nature of this disturbance, as well as recover any bones, flint flakes, or tools that might be in this disturbed soil."

I guess that means we’re narrowing down where the skeleton is, but it could be really broken up.

This was my first archaeological dig and I had a great time.  During my lunch break, on the grass by a bog, I just enjoyed staring at the trench and the square plots marked with staked string and the tools--all under a tent--and the nearby screens to sieve the soil removed from each plot.  And I was sobered by the thought that this was the cemetery of a mastodon who died maybe 12,000 years ago!

To keep up our morale, Dr. Brush made sure we all got to see and touch every find; the one I remember was a piece of tooth which seemed to be about an inch in diameter and length.  I read that a mastodon tooth can be 6 ½ inches long.

I spent the day on the Unit 4 team, with three of the  ten College of Wooster students volunteering on the dig.  Two of us worked on removing the first 10 centimeter layer, while other two sifted the soil and put anything possibly interesting into a small paper bag.   To dig carefully, we stuck the point of a trowel into the dirt and then twisted the trowel, to upend the soil.  If we struck something hard or interesting, we put the trowel aside and brushed away dirt to expose it and then carefully removed it.

Once it became obvious that we weren’t likely to find anything in the first 10 centimeters of Unit 4, I was able to dig with a regular size scraper shovel, shoveling off thin layers while the student members of the team sifted.

I soon learned to spot sandstone, since it easily resembles bones to a novice like me.  One of the students also advised me that bones usually don’t show up as white.

I also met co-leader Dr. Nick Kardulias, chair of the archaeology program at the College of Wooster.

Dr. Brush said that there were more than 30 volunteers on both Saturdays.  In an earlier report, he said that on the first day the volunteers included 10 Ashland University students and 5 College of Wooster students.  The Ashland students couldn’t come on August 30, because unlike the Wooster students, they had a Labor Day break from school.

I'll return for the next dig on Saturday, September 6.

The soil from the plots is sieved through a screen at the teepee-like frames to the right of the tent-covered plots.  (Photo by Don Comis)