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Fall 2012 Progress

16 Sep

The Mammoth News

Fall 2012, Volume 25

Final Lab Work

This term we worked on the last of the bones that we had previously brought in from the field. These included two large clusters of vertebrae, a field jacket with two ribs, and a small rib piece that connects to another rib piece found under the skull. We had sawed through this rib in the field to remove the part that extended beyond the skull block first. The rest of the rib became part of the skull block and was removed from it in the Science Center several years later.

Final Field Work

This fall in the field we had a geotechnology company run a ground-penetrating survey around the perimeter of our excavation pit in an effort to find some bones we had not found yet. The survey results did not strongly indicate that there was bone to be found, but the class made a mammoth attempt to find the missing pieces – the pelvis, the left tibia, the left ulna, to name the big ones. We worked hard, motivated to find the pieces, but as the term went on, motivated also to stay warm. A few of the mornings we started work with air temperatures in the 20s (F), but usually in the 30s. Facilities helped by removing the upper three feet of loess (wind-blown silt) with a Bobcat, while we removed the lower three feet with pickaxes and shovels. Since this was our last term, unless we found more than we could remove, we piled the dirt on the opposite side of the pit, rather than carry it to the surface as in the past; however, we still had to get it to the top of the pile. You’ll be able to see in the photos how big this pile of dirt was at the end of the term.

We found no bones in spite of all our digging, so I have officially closed the excavation. Facilities will be removing the shelter, reusing it to cover some of their used materials. They will fill in the pit (no, it won’t be lined with concrete for a pool, sorry).

Outreach

Visitors
We had about 100 visitors come for tours of the excavation site, lab, and skull block. These included A/U Discovery Bound participants, the Principia 4th Grade class, a large group of professional biologists from the area, a biology professor from SIU-Edwardsville and some of his students from his Mammalogy class, as well as walk-ins. I had to turn away several requests due to lack of time on our part.

Outreach continues with this project as people still want to see Benny, our mammoth, and learn about this amazing prehistoric animal and its surroundings. I have a tour lined up in March for the Parkway Schools System Community Schools adult group. The SIU-E Biology Department has invited me to give a talk for their weekly colloquium series on our mammoth this January. Community interest in our project continues.

Field Trips
We took our usual field trip to the Illinois State Museum where Jeff Saunders and Chris Widga show us their collections of mammoth and mastodon bones, as well as other cool fossils and some nice minerals from Illinois. It’s especially fun to see teeth and other skeletal elements of some of the mammoths we read about in class. Then we visit the Changes exhibit at the museum, which puts the Pleistocene (Ice Age) in the perspective of geologic time. Thank you, Jeff and Chris!

Next Steps

With the excavation pit closed and the last bones prepared in the lab, I won’t be teaching the Ice Age Mammoth course anymore. The mammoth project has been a wonderful learning opportunity not only for the Principia College students who took the course, but for students of all ages and others from the area as well as our alumni and friends from around the globe. My students and I regularly gave tours as part of the course. We have hosted over 9000 visitors over the past 11 years!

The next big task is displaying some of the key pieces of the mammoth in the Science Center. Last year I invited bids from a couple of different museum display experts to create and install a professional interpretive display in the Science Center. Our plan is to place this display in the atrium of the building, just outside the newly renovated aviary, and to incorporate into the display the skull block (with the tusks), some of the major bones, and educational information about the mammoth. We are awaiting approval from the College administration to spend the funds for this project, but once approved we expect to begin the installation process.

-Janis Treworgy

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Fall 2011

28 Nov

The Mammoth News

Fall 2011, Volume 24

Field Work

This fall in the field we moved the west wall back about half a meter in hopes of finding the elusive pelvis. We came up empty handed, but it was a good experience working in the loess and learning the proper digging techniques. We came indoors just as the outside temperatures at 8am were too cold to be comfortable.

Lab Work

In the lab, we opened a large plaster jacket containing a cluster of bones identified on the map as ribs and vertebrae. The cluster had been adjacent to the skull block in the field. After several weeks of careful work on this cluster, we found and prepared three ribs (12-18 in long), several smaller rib fragments, a thoracic vertebra, and another interesting piece we have not been able to identify yet. The latter is only part of a bone and is in a pile of bones that includes rib fragments and the vertebra, making it difficult to identify. It may be another vertebra.

We opened two smaller field jackets too this term. One encased a thoracic vertebra, which the students were able to prepare nicely, and the other was part of a rib that we were able to match up with a previously prepared rib segment. This rib had been cut in the field because it crossed clusters of other bones. Because we have been carefully mapping bones found in the field, taking photos of bone clusters before removing them, and labeling the field jackets, we were able to reunite these rib pieces. It’s nice when all that work pays off!

Outreach

Visitors

We had about 100 visitors come for tours of the excavation site, lab, and skull block. These included the Principia 4th Grade class, Triad High School science class from Troy, Illinois, and a group of the Newcomers and Neighbors of Edwardsville/Glen Carbon, Illinois. I had to turn away a couple of requests due to lack of time on our part.

Field Trip

We took our usual field trip to the Illinois State Museum where Jeff Saunders and Chris Widga show us their collections of mammoth and mastodon bones, as well as other cool fossils and some nice minerals from Illinois. It’s especially fun to see teeth and other skeletal elements of some of the mammoths we read about in class. Then we visit the Changes exhibit at the museum, which puts the Pleistocene (Ice Age) in the perspective of geologic time. Thank you, Jeff and Chris!

This term we also visited the Missouri History Museum in St. Louis to see the special exhibit, Mammoths and Mastodons: Titans of the Ice Age. It features the best preserved mammoth ever found, a one-month old baby, called Lyuba, found in Siberia in 2007. Her skin, a bit of hair, and inner organs were all preserved! I took a class to this exhibit two years ago when it was in Chicago at the Field Museum, so it is nice to have it so close to campus. ☺I highly recommend this exhibit to anyone in the St. Louis area; kids of all ages will love it. In March, we will host a field trip at our mammoth site and lab for members of the Missouri History Museum as part of the exhibit activities. I will be giving a talk at the museum too.

Update on Last Summer’s Find

You may recall that last summer a contractor discovered well preserved spruce in some hard white material, thought to possibly be clay. We have since determined that it is probably part of backfill material in a former trench. The white material looks like some kind of plaster, but we are getting it analyzed and will know more later. This means that the spruce is from a modern tree. While that is disappointing, it is great to know that we have contractors who are keeping an eye out for possible fossils and artifacts.

-Janis Treworgy

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Spring 2011

28 Jun

The Mammoth News

Spring 2011, Volume 23

 

Field Work

We started the term by setting out a grid of points, spaced a meter apart, on the ground surrounding our excavation site for running an earth resistivity survey, one remote sensing method that could possibly help us find where some of the missing bones are located. Dr. John Sexton from Southern Illinois Carbondale and a few of his students taking a class in geophysics brought their equipment on the first Saturday of the term to run the survey. Unfortunately the resistivity equipment did not function properly, so we ran a magnetic survey. Since Benny’s bones don’t appear to have iron minerals in them, we didn’t expect to get usable results with this method, but it showed my students the process involved in careful data collection in the field. They also learned how challenging it can be as equipment failure is an unfortunate part of field work at times. Laying out the grid was a good exercise too.

We decided to dig to the south this term, taking the entire wall back half a meter. We had our Facilities crew remove the upper terrace of dirt, then we proceeded with pick axes and shovels to remove the lower 1m to near the bone level. We moved right through the bone level without finding any bones for the first time this term. Next term we’ll try a different direction.

Lab Work

Postcranial Bones

After finishing the south wall without finding any new bone, we moved into the lab, where the students were guaranteed to find bone as they worked on two clusters of bones removed from the pit in 2004. They learned how to remove the plaster field jackets and then worked from the underside of each piece removing matrix to expose the bone. One cluster revealed two of our best preserved and longest ribs found to date. The other cluster contained two smaller and not so well preserved ribs, a couple of rib pieces, and a poorly preserved thoracic vertebra. We also cleaned an isolated thoracic vertebra.

Exhibiting Benny

I have been getting quotes for mounting and displaying the skull block in the atrium of the Science Center and building a display of the rest of the mammoth upstairs where the mammoth lab currently is in the Interpretive Center. We will need to have a major fundraising effort before we can begin the first task of mounting the skull block. If any of you are interested in contributing to this effort, please contact me. Many decisions are yet to be made regarding the best way to proceed with this phase of the project. I’ll keep you posted.

Outreach

Visitors

We had 217 visitors come for tours of the excavation site, lab, and skull block. These included Principia College parents, families from St. Clair County Christian Home Educators, a group of the Newcomers and Neighbors of Edwardsville/Glen Carbon, IL, Wolf Scout Den #2 Pack #31 in IL, various senior citizen groups touring the campus, and occasional drop-ins.

Talk

Janis Treworgy gave a talk about our mammoth project to the St. Louis Rock and Gem Society in March 2011.

Summer News Flash!

An alert outside contractor, Don Lewis, working on the water main project on campus found an unusual white rock-like specimen with a very well preserved spruce branch imbedded in it while they were removing Peoria loess, a uniform silt deposit, from one of the trenches. The spruce needles are incredibly fresh for being encased in this indurated material, indicating that they must have been buried quickly, like our mammoth. The white matrix may be a relatively hard clay with some dolomite (slow fizz with dilute HCl), and may be a deposit in an ancient (ice age – Quaternary) small pond present in the area. The trench is right next to the road and just down slope of the women’s softball field (3rd base line) so it seems unlikely that the loess is in place, but we haven’t ruled that out yet. That would make the sample much more valuable to us.

My husband, Colin, and I met the contractor and his family the next day, Saturday, at the college to look at the specimen and figure out what it was. We scraped a vertical section in one wall of the trench to get a fresh surface of the loess in order to sample it at various measured depths. We found a couple of lenses of soft clay in the loess, which is unusual to find in the Peoria loess, suggesting that the loess is fill material. The contractor and his family all participated in helping us measure the depths, sample the loess, and take notes. It was a great educational opportunity! I then gave them a tour of the mammoth site, lab, and skull block, which they loved. We are grateful to Don for his alertness.

I have contacted experts at the Illinois State Museum and Illinois State Geological Survey to determine interest in the specimen. Eric Grimm, a palynologist (studies ancient plants) at the ISM, and Dave Grimley, a Quaternary geologist at the ISGS, are excited by the photos I sent them of the specimen, but concerned about whether the loess is in place. If it is in place, we will get a radiocarbon date from the spruce needles. It also may be possible to get DNA from the specimen so my colleague Chrissy McAllister has taken the sample to Saint Louis University where it is being stored in a freezer that maintains a constant temperature of -20° C. If we decide the loess is in place, I will likely have my fall mammoth class help auger a hole adjacent to the trench to determine exactly where the specimen was found stratigraphically – where in the Peoria loess it occurred. This will help us know if it was from the same time period as our mammoth. I’ll keep you posted as we learn more.

-Janis Treworgy

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Fall 2010

28 Nov

The Mammoth News

Fall 2010, Volume 22

Field Work

This term we continued excavating in the field, shaving away walls about a half meter deep on the north and south sides of the site. On each side we found a rib, neither of which were well preserved. This brings our bone count to 145. We are still missing some key pieces – pelvis, left tibia, left ulna and radius, both fibulae. We have some pieces in the lab that may be parts of these bones, but no sign of the pelvis yet. After several weeks in the field, we successfully removed both of the ribs, mapping them and plaster jacketing them. Then we moved to the lab to gain experience there too.

Lab Work

Postcranial Bones
In the lab, the students learned how to remove the plaster field jackets and then worked from the underside of each piece removing matrix to expose the bone. The underside of the bone is generally better preserved because it has not been exposed to the elements as long before the bone was buried. The class proved to be quite efficient at lab work and completed six pieces in the few weeks they worked there – five ribs and a small block that included what appear to be poorly preserved parts of two vertebrae (?). The vertebrae (?) and three of the ribs were removed from the site in the Spring 2010 term.

Skull Block
In the garage I had some teaching assistants working on the tusks. They were tasked with getting at the hard-to-reach parts of the tusks, repairing broken sections, and painting the repaired sections. Painting was done by a TA major in graphic design. We are nearly finished with preparing the skull block.

Looking Ahead. I am in the process of contacting people who can mount the skull block in the atrium of the Science Center. This will be a huge undertaking because of the not-so-perfect condition of the skull and tusks. We have to be so careful moving them, and yet we will need to turn them over again to build a support system for the underside, turn them back again to upright, tilt the block to get it out of the garage, around through the machine shop, which has double doors into the hallway, down the hall and into the atrium – the long way around when we are only 30 feet from the destination now, but separated by only a single door. Each time we move this block we have to rejacket it and secure it to a frame to keep from damaging it. This will be a challenge!

Outreach

Visitors

We had 120 visitors come for tours of the excavation site, lab, and skull block. These included participants on a public field trip sponsored by the St. Louis Science Center, the Principia 4th graders, science students from Triad High School in Troy, IL, the Chesterfield Montessori School 1st graders, and occasional drop-ins.

Talk

Janis Treworgy chaired a session at the Geological Society of America Annual Meeting in Denver on solitary geoscience faculty doing research with undergraduates (yes, there are others in my situation). She gave a talk on projects she does with students including the mammoth project.

-Janis Treworgy

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Spring 2010

26 Jun

The Mammoth News

Spring 2010, Volume 21

Field Work

This Spring we reopened the excavation pit for the first time in five years! Since removing the skull block in the Summer of 2005, we have worked indoors on continuing to excavate and prepare the skull block and other bones removed from the pit in our garage and lab. We are nearly finished with the skull block, so it was time to return to the pit to look for more bones. We expected to find more bones in the area to the west based on results of a ground-penetrating radar survey performed in the spring of 2004 by Dr. Dan Joyce, archeologist and Senior Curator of Kenosha Public Museum in Kenosha, Wisconsin. So we removed leaves from the pit, reinforced the steps, improved the drainage around the pit, shoveled fill dirt from the west end of the pit to the east end, brought in the Facilities crew and their backhoe to remove the upper three to four feet, and then started digging by hand to reach the bone level.

Early in Week 4 we found our first bone, right at the depth we had expected based on the previous excavating work. Eventually we found a total of four bones – three rib pieces and an irregular cluster of bones that we think are connected. The rib pieces include a couple that are over 35 cm long and up to 7 cm wide and a third one that is much shorter and narrower. The irregular cluster cannot be identified for certain yet, but may be part of the pelvis. All four bone pieces were found within 1.5 meters of each other. No other bones were found this term after digging down about 15 cm below the paleosol that marks the bone layer.

We estimate that we removed about 12 m3 of dirt this term. Fortunately I had an eager group of workers that developed a great sense of teamwork and had an awesome work ethic.

At this stage, we have only small, delicate sections of the tusks to finish cleaning, repairing, and stabilizing. This remaining work will probably be done by some of my experienced teaching assistants while the next class will reopen the pit to continue the excavation for new bone material to the west.

Lab Work

This Spring the class did not work in the lab. A teaching assistant did some repair work on the tusks. Some repair work is all that remains to be done on the skull block.

Outreach

Visitors

We had 150 visitors come for tours of the excavation site, lab, and skull block. These included the Godfrey Women’s Club, the Great Rivers Audubon Society, the Geology Club from St. Louis Community College at Meramec, the Eastern Missouri Paleontological Society, the Science Club from St. Francis School in Jerseyville, Principia parents of current students, visiting prospective students, and occasional drop-ins.

Talk

Janis Treworgy gave two talks on the mammoth project to local groups off-campus, including the Eastern Missouri Paleontological Society in St. Louis and Great Rivers Audubon Society in Illinois.

-Janis Treworgy

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Fall 2009

28 Nov

The Mammoth News

Fall 2009, Volume 20

Lab Work

This Fall our class started in the lab working on one cluster of broken bones that had been adjacent to the skull block in the field (4N-1E) and another cluster of rib pieces from the southwest part of the pit in 2N-3W. We turned each cluster upside down relative to its position in the field, and removed the field jacket from what was now the upper half. As we removed the matrix, each student found bone in his/her section, which is always exciting. In the block adjacent to the skull, we found several rib pieces and a part of a cervical vertebra. We were able to connect some of these rib pieces to rib pieces found under the skull block – bone pieces we had to cut in the field in order to get the skull out more easily. Careful mapping of the bones in the field and labeling of pieces brought to the lab made this possible.

Final cleanup and some repair work were done on the right ulna and radius and they have now been completed.

Late in the term we worked on the skull block. We first removed about an inch more of the jacket under the skull to verify if we had cleaned down to the area on the skull we had cleaned from the other side. Only a few areas needed additional work, which we completed. We removed several pieces of rib that had been under the skull in the field (resting on top of the skull in its current position). These rib pieces were matched with the pieces uncovered this term. We also unjacketed, cleaned, repaired, and consolidated additional sections of the tusks. One area on the right tusk that received repair work (Paleo Sculp) was the section struck by the backhoe in 2002 when the pit was initially being opened. Additional repair work will be needed as we unjacket more of this fragile part of the tusk.

At this stage, we have only small, delicate sections of the tusks to finish cleaning, repairing, and stabilizing. This remaining work will probably be done by some of my experienced teaching assistants while the next class will reopen the pit to continue the excavation for new bone material to the west.

Field Work

The current plan is to reopen the pit in the spring 2010 to continue excavating toward the west.We have not excavated since the summer of 2005 when we removed the skull block. We expect to find more bones in this area based on results of a ground-penetrating radar survey performed in the spring of 2004 by Dr. Dan Joyce, archeologist and Senior Curator of Kenosha Public Museum in Kenosha, Wisconsin.

Outreach

Visitors

This term we had a couple of large groups and then several individuals visit. We always enjoy hosting Principia’s Fourth Graders because we let them each make their own plaster-of-Paris cast of a mammoth or mastodon tooth. Both the fourth graders and my students always enjoy this activity. The kids also enjoy getting to see the big bones in the lab as well as skull block.

Dr. Jeff Saunders, Dr. Chris Widga, and Mr. Paul Countryman, all from the Illinois State Museum, visited us this term and helped us think about next steps for the skull block to prepare it for display. Paul is the Museum’s Exhibit Production Chief, and he helped us figure out how we can display the skull block. We are so fortunate to have these experts work with us and help us problem solve. There is no formula for going about most of this work. Each project is different. Subsequent to their visit, one student, an art student, did a concept sketch of what the display area (in the atrium of the Science Center) might look like. Other students built a cardboard model the size of the skull block that we will need to move into the display area, and we walked it along the course we will need to take.

Talk

Janis Treworgy gave a talk at the Geological Society of America conference in Portland, Oregon, on ways of surviving and even thriving as a solitary geologist at a college. This was part of a session on that topic that she co-convened with a colleague. She discussed the opportunity she has to do authentic research with her undergraduate nonmajor students through the mammoth project.

-Janis Treworgy

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Spring 2009

28 Jun

The Mammoth News

Spring 2009, Volume 19

Lab Work

This Spring our class started in the lab working on a large cluster of broken bones that had been adjacent to the skull block in the field (3N-1W). We turned the piece upside down relative to its position in the field, and removed the field jacket from what was now the upper half. This always takes longer than we expect, but once done, we removed the matrix, keeping a level surface as we worked our way down toward the bone that we knew we would find in the lower part of the block. It’s always exciting when each student finds bone in his/her section, which they all did. Everyone worked on this block at some point, and a few students stayed with it all term and helped with the final stages of labeling and preparing the pieces for storage. We found three large pieces that appear to be sections of the left ulna, our first broken limb bone; the question remains as to when it broke – during his life or after his death. We also found three metapodials (foot bones) a couple of wrist bones (?), several rib sections and fragments, and our first caudal vertebra (tail bone).

The class also removed the second half of the field jacket from the right ulna and radius, which are articulated (connected) as in life. We used a dremel and hand saws. The other side had already been prepared, and the bones were resting in a storage jacket we had built to support and protect the bones. The side we worked on this term had been exposed to the elements prior to being buried by the wind-blown silt (loess); it was therefore not as well preserved as the other side. These bones required a lot of patience and meticulous work. After we had cleaned and consolidated the bones and done some repair work, we built a storage jacket with feet for this side of the bones. We always love working with plaster!

We made good progress on the skull block this term. We unjacketed, cleaned, repaired, and consolidated the remaining sections of the tusks leaving about a foot of each one under the support bars still to be prepared. The sections of tusk we worked on are in fairly good condition. The exception is the part of the left tusk that had been in contact with the right tibia. The tibia had been under the tusk when the skull block was upside down, as we found it in the field, and both the tibia and tusk were damaged by being in contact for so many years. We filled in the damaged section of the left tusk with a putty-like material that hardens (Paleo Sculp). The tusks are looking quite majestic. Check the photos to see them. The sides of the skull were cleaned this term as well. We are near the sections cleaned from the other side. We are getting close to finishing our preparation of the skull block!

Outreach

Visitors

This term we had a variety of visitors for whom we gave tours including Fifth and Sixth Graders from Fieldon Elementary in Jersey County, Fifth Graders from The Wilson School in St. Louis, Preschoolers from Principia School, the St. Louis Rock and Mineral Society and several small groups, including three visitors from Nepal. Our visitors from Nepal are quite familiar with elephant behavior and were able to confirm that the hole in Benny’s skull could not have been caused by a tusk of another mammoth because the forehead (frontal bone) is too thick, the tusks are not curved correctly to make that type of impact, and elephants (and presumably their close cousins, mammoths) don’t aim to kill when they fight for mating rights. Dr. Jeff Saunders, Dr. Chris Widga, Mona Colburn, and Meredith Mahoney, scientists from the Illinois State Museum, visited us this term and helped us identify some of the pieces of bone we had in the block we’d been working on. We compared bone shapes to of other bones we had as well as to some bones of an African elephant that we have borrowed from the Museum. We love having them visit.

-Janis Treworgy

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Fall 2008

28 Nov

The Mammoth News

Fall 2008, Volume 18

Lab Work

This fall our class started in the lab working on a cluster of broken ribs that overlapped one another. It was like pick-up-sticks! Preservation was not good, but it was a useful exercise in learning how to clean and consolidate bone. Among the ribs was a relatively well preserved bone from the proximal end of the rear foot called the calcaneum. Another bone that we worked on was the first bone removed from the pit in the summer of 2002. It appears to be one of the sacral vertebrae, five of which fuse as one piece to form the sacrum. The sacrum is fused laterally with the pelvis, anteriorly with the lumbar vertebrae (lower back bones) and posteriorly with the caudal vertebrae (tail bones).

We also worked on the skull block. We unjacketed the tusk socket area where the tusks protrude from the skull and uncovered both tusks and their sockets. The sockets are broken up perhaps due to rotation of the tusks after the organic material had decayed. We found a rib that had been buried under the tusks in this area as well. We also worked on the tusks from the tip end, continuing from the spring. We have encountered damaged areas on both of them that requires great care in cleaning and consolidating. They are cleaning up beautifully!

Outreach

Visitors

The term we had a variety of visitors for whom we gave tours including the Trustees Council, Cub Scouts from Hamel, IL, Fourth Graders from Principia School, and several small groups from the area.

Conference

We helped host the Leadership Conference for Discovery Bound, a program for high school-aged Christian Scientists, by giving participating students the opportunity to tour the mammoth lab and make plaster-of-Paris casts of mammoth teeth.

Homecoming

We had a tent at Homecoming where people could see photos and bone casts of mammoths and kids could make a plaster-of-Paris cast of a mammoth or other Proboscidean tooth to take with them.

-Janis Treworgy

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Summer 2008

28 Aug

The Mammoth News

Summer 2008, Volume 17

Lab Work

This summer we had adults in Principia’s Summer Session work in the lab on a cluster of ribs that had been removed from the excavation site by a previous Summer Session class in 2003. We removed much of the matrix from the underside and found several ribs and a more massive bone that we could not identify in the field. We also began work on another bone that we could not identify in the field; this was the first bone that we removed from the pit in the summer of 2002.

Outreach

Visitors

During Summer Session I gave a tour of the lab and skull block to about 60 people.

Local News

Terry Hillig of the St. Louis Post-Dispatch came to see our progress and interview me for another article. He also interviewed Dr. Jeff Saunders by telephone. Terry’s first article was printed in January 2005 and picked up by papers across the country.

-Janis Treworgy

 
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Spring 2008

28 Jun

The Mammoth News

Spring 2008, Volume 16

The Skull Block and Its Hidden Treasures

This spring term we uncovered a large portion of the top side of the skull, the side that was down in the field, and found several intriguing features. After uncovering most of the top surface, we discovered that the skull is relatively complete but collapsed, probably due to compaction after it had been turned upside down some 17,500 radiocarbon years ago. Compaction would have occurred early as deterioration of bone began, probably after it was buried by the wind-blown silt.

We have also exposed on the skull the right cheek bone, fragile and complex bones in the roof area of the mouth, the attachment area for the trunk, and the two ends of the tusks within the skull where the tusks form and grow. The left tusk has remnants of the tusk socket (alveola) attached, but it appears that the alveola had broken and pieces had shifted prior to burial. This suggests that the left tusk may have rotated in the socket due to its own weight as muscle tissue deteriorated. The alveola on the right tusk appears to be more intact. However, we have not yet completely excavated either alveola.

In the top of the skull we have found a hole or conical shaped indentation (about 5 cm across) that possibly was caused by impact from a tusk of another male mammoth. We have yet to completely prepare this part of the skull and get an expert opinion on the hole, but this idea is intriguing – fighting mammoths! This would explain Benny’s demise. Males fought annually, but generally not fatally, for mating privileges. If this hypothesis is confirmed, then we need to make a case for changing Principia’s mascot to a mammoth – the Fighting Mammoths!

We have also enlarged our Pleistocene fauna finds to include a gray wolf – Canis lupus – and possibly another rabbit! Just above the skull, which would have been beneath the skull when they were buried, we uncovered two bones that we knew right away were not mammoth bones. We sent the bones to the Illinois State Museum where Dr. Jeff Saunders’ colleague, Dr. Chris Widga, identified the larger one as part of the lower leg bone (tibia) of a gray wolf. The smaller bone was part of the second smaller lower leg bone (fibula). Perhaps the wolf died while scavenging the mammoth carcass, but before the skull block had been turned over by, perhaps, another mammoth passing by. It is also possible that this wolf was part of a pack of wolves that was bringing down our mammoth, and it was killed by a blow from one of Benny’s tusks or legs. We also found a few small teeth that are currently being identified – possibly another rabbit.

We uncovered the tusk tips for the first time this term and discovered that they are both complete, coming to a tapered end. Careful excavating and repair work were needed on both tusks, but they are looking beautiful now! A small rib fragment was found against the left tusk. Much more of the tusks remain to be prepared in the fall.

Lab Work

This term in the lab we prepared a number of small bones and continued work on some long bones making the following progress:

The small bones that were prepared included one rib piece about 35 cm long, some bones from the hands (metacarpals), an isolated end section from a long bone, several unknown small bones or bone pieces, and the atlas (first neck vertebra behind the skull). Students sawed off the plaster field jackets, removed matrix, cleaned, and consolidated these bones with butvar.

Right tibia – The side of the tibia that had been exposed before burial and in contact with the left tusk was prepared. This side shows more weathering than the other side and has damage where it was against the tusk.

Right ulna and radius – Preparation of one side of these articulated bones was nearly completed by Rachel Lindstrom over the winter of this year as she was preparing to measure Benny’s long bones for her senior capstone project. Students finished preparing it this spring.

Senior Capstone Project – What Species Is He?

Rachel Lindstrom chose to measure the long bones (leg bones) of our mammoth and compare them to comparable measurements of mammoths identified as Mammuthus primigenius (woolly mammoth) and Mammuthus jeffersonii (Jefferson’s mammoth). Based on teeth measurements made and overall characteristics noted by Jeff Saunders, we think Benny belongs to the latter species. Recognizing the fact that Benny is only one individual and may not represent the average size for his species, Rachel found that his long bone lengths are closer to those of a Jefferson’s mammoth than a woolly mammoth. A Jefferson’s mammoth was larger than a woolly mammoth, and, according to Jeff Saunders, its habitat was open woodland (spruce) in the Great Lakes region of North America.

Dr. David Grimley of the Illinois State Geological Survey notes that terrestrial gastropods (snails), typical of boreal woodlands, and occasional spruce wood have been found in the Peoria Silt (a loess deposit) in uplands and sloping areas adjacent to the floodplains of the Mississippi River in the St. Louis Metro East region (e.g. near Collinsville). The Peoria Silt is the unit that entombed Benny. Early in our project we sifted the Peoria Silt as it was excavated, but found that it is too leached of carbonates to have preserved snails. Based on previous studies of gastropods and ostracodes in the region (Leonard and Frye, 1960; Grimley et al., 2001; Curry and Delorme, 2003), it is envisioned that the Principia campus area would have been an open woodland environment (or parkland-type area), well suited for a Jefferson’s mammoth. During the time of Benny (~17,500 radiocarbon years ago), borealtype woodlands likely occurred in hilly areas along the bluffs, protected ravines and small stream courses, whereas the broad Mississippi-Missouri Valley below (the American Bottoms) more likely consisted of grassland and wetland type vegetation in a shifting braided river environment. More open grasslands may also have occurred in the flatter plains to the north and east of Principia interspersed with areas of woodlands. Climatic reconstructions for the St. Louis region based on ostracode fossils suggest a mean annual temperature about 10 degrees Celcius cooler than today during the last glacial maximum (Curry and Delorme, 2003), with a modern analog occurring in the boreal forests or parkland areas of central or south-central Canada.

Outreach

Visitors

During this term we hosted about 160 visitors including six area school groups ranging from preschool to high school and a few adult groups. We hosted one 5th grade class for a tour and activities that included making plaster casts of mammoth teeth. My students participated in all of our tours as guides explaining what we do in the field and lab and what we have learned about mammoths.

Local News

Channel 4 (KMOV/CBS) News in St. Louis returned May 20th to do a follow-up story on what we had found in the skull. They again shot some footage during the day and returned that night with crew and a satellite dish to do the story live from our Science Center garage where the skull block resides.

Talks

Janis Treworgy gave three talks this winter to about 240 people for the following groups:

  • Jerseyville Historical Society Annual Meeting
  • Madison County Soil and Water Conservation District Annual Meeting
  • Illinois State Museum’s Paul Mickey Lecture Series in Archeology and Natural Sciences

-Janis Treworgy

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