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Thomas Farm Volunteer Dig--April 2016

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digit

I took the opportunity to volunteer with the Florida Museum of Natural History (FLMNH) in April of 2014 and had a great time (though it was off to a rough start with a rain out on the first weekend we tried. We finally did manage to do some digging and found a spectacular carnivore mandible toward the end of the dig which was our "trip-maker". For anybody who missed this tale, you can find it here:

http://www.thefossilforum.com/index.php?/topic/45220-thomas-farm-volunteer-dig-spring-2014/

I missed the Thomas Farm dig in 2015 as I was out of the country playing a coral reef scientist on TV (one of my numerous avocational interests). When the opportunity came around this year I jumped on it. Because of the new Montbrook site that the FLMNH is working this year, they are spending a limited time (5 days) at Thomas Farm this year--so not wanting to miss any of the fun, I signed up for the entire 5 day dig. The new Montbrook site dig will continue through mid-May and I encourage any who have the opportunity to give it a try. I'll probably try to get back there once more before the end of the season. Here is my report from a month ago:

http://www.thefossilforum.com/index.php?/topic/63056-volunteer-dig-with-the-flmnh/

So anyway, back to Thomas Farm. The section I was digging back in 2014 (which they continued in 2015) was now dug down deep enough that they wanted to balance out the area by going back to a section that they haven't dug for several years. When I was there last it had an aluminum frame car port with a canvas top covering a cache of sandbags and some other stored gear. They moved all of those sandbags up out of the digging area to ground level near the outbuilding on site. The plan is to dig this area down to match the level of the adjacent section which is now quite a bit lower. They like to try to keep things relatively level as it promotes good water run-off during the rainy season (though Florida seems to have nothing but a rainy season this year).

For anybody who has been to the Thomas Farm site in the recent past, here is what the site looks like now:

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digit

The grid square that I was assigned to dig had a horse leg bone already exposed toward the middle of the back boundary of the square. Last week was the Hummingbird Challenge hosted by Dave Steadman and other FLMNH scientists. It is a chance for people to dig at Thomas Farm and hear presentations on the site and the quest for tiny bird fossils from the site--possibly even bones from hummingbirds which were just coming into existence some 18 million years ago which is the age of this fossil site.

The task for me was to remove matrix material from the rest of this square down to the same level that had already been reached in other parts of the grid square. This would help to allow enough room for this horse bone to be properly jacketed. You can just make out a bit of detail in the dark brown bone in the middle of the pedestal that someone had started forming.

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I continued, with flat blade screwdriver and dental pick, removing the matrix and tossing it into a waiting plastic sandbag. The matrix material is layered with gravely, sandy, and sticky clay layers alternating throughout the depth. Mostly the section of the matrix I was removing was rather fossil-free but I did come across several dark brown pieces--though when they were probed further, most turned out to be small bone chips. Later in the afternoon, I made my first interesting find. It was a small piece and as I dug it up and then cleaned off the sticky clay that was obscuring its shape, I could see it was a small tooth. Initially, I thought it might be an artiodactyl tooth (a deer or small camelid) due to its shape. Once I had it cleaned-up a bit I showed it to Jason from FLMNH and he properly identified it as Parahippus molar. It's a good thing when you have enough knowledge to identify your find as a tooth (pretty basic) and as a molar (a little better) and be able to make a guess as to what type it could be. It's even better when you are wrong but can find out the true identity and learn a bit so you know more than you did a minute ago. Here's this little lesson as it came out of the ground and a bit more cleaned up.

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Within a few minutes more I saw the telltale sign of more bone (bones here are conveniently a dark brown color which contrasts well with the yellowish sand and gray or golden colored clays). As I cleaned around it a bit more with a dental probe I could see two ridges that looked a lot like the Parahippus molar I had just found. A few minutes more and I could see that this was indeed a confirmation of my recent lesson--for which which I now had a working search image.

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These teeth were pretty fragile so they each were placed in their own plastic vial with a wad of toilet paper to keep them from sloshing around.

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digit

It was a bit of a slow day for me and the only other notable finds that turned up came shortly after the two Parahippus molars. While I worked down the level of my square I finished the back left corner and started working my way to the right--closer to the horse leg bone on its pedestal. I heard a scrape when loosening material with the screwdriver. Brushing away the loose material revealed a dark speck of that same dark coffee grounds brown coloration. A little probing with the dental pick showed this was a small isolated item and after a bit of cleaning of the surrounding material I was able to lift up the piece for closer inspection and cleaning. As the material dropped off the piece I could see it was a toe bone with a rounded end and a concave side opposite where the phalanx would have articulated with the other bones connected to it. This one was really tiny--smaller than any I had found back in 2014. A quick presentation to those more knowledgeable to me at the dig site confirmed my analysis--this was a toe bone of the genus Archaeohippus, a genus of smaller horses likely only weighing in at around 20 kg. A perfect lap horse (as in lap dog--not laps around a racecourse :)).

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The only other item of interest was found not to far from this toe bone. When I first spotted it my instincts were working adeptly. I could see a faint keeled ridge emerging from the clay and what appeared to be pockmarked holes. At about the size of a quarter, it was exactly as I had suspected--a gator osteoderm. I found several of these at the Montbrook site but they were all bone white while this one was in the dark chocolate tones characteristic of Thomas Farm.

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digit

That was pretty much the sum total of my finds for the first day. It was approaching 4:30pm--quitting time--and so I began to clean-up my spot for the day. I did a little bit of material removal from the front edge of the pedestal with the horse leg bone and then started cleaning up.

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One of the things I needed to do was to keep the leg bone from drying out too much before it could be jacketed so I laid back on some damp PT--Paleo Tissue (aka TP--Toilet Paper). I then topped this with a plastic collection bag and a couple of kneepads before pulling a small carpet square over it to keep it safe through the night. Here is my completed square at the end of the day.

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My plastic bag for finds was pretty sparse. A few larger bone fragments loose in the bag and a pill vial packed with small chips and shards of bone. The other two vials, packed with that versatile Paleo Tissue, contain the two Parahippus molars. Not a lot of finds for removing three sandbags full of matrix from the square. These will join the army of sandbags waiting to be washed and screened for micro fossils.

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digit

When I was here before in 2014 it was so humid from recent rains (and overcast) that we didn't do any washing of the matrix to screen out micro fossils. Unless the washed matrix can dry out enough to get it out of the sifting screen and into plastic bags they don't even attempt to wash any matrix. This year we've got sunny skies and low humidity so it is a perfect time to reduce some sandbags to small plastic bags of concentrated matrix to be searched at a later time back at the museum.

Over the years they have accumulated quite the backlog of sandbags. Each bag has a date written on it to indicate its vintage. Inside of each bag is a piece of paper with all of the collection information written on it--enclosed in a small zip-top bag to keep it fresh.

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The matrix inside the bags are first dried out which causes the clumps of clay to shrink and crack. The matrix is then loaded into a 5-gallon bucket and filled with water to permeate and break down the matrix into a sloppy slurry. After a bit of soaking, the bucket is emptied into a wood and mesh sifting screen. The screen is a fine window screen mesh in a sturdy wooden frame. A smaller square screen with 1/4" mesh is placed over the top as the slurry is poured in.

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The coarse screen filters out any of the larger chunks of rock and any sticks or other large debris. Any fossil material larger than 1/4" that gets caught in this screen is easily seen and moved manually to the lower screen. The rest of the larger material is dumped out. A hose is then used to wash out the rest of the sand and silty mud leaving behind only the small gravel, bone fragments and micro-fossil material.

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digit

The screens with the washed micro-matrix are then set out in the sun to dry out. It was interesting to look at the row of sifting screens and view the material left behind in each of them. In some screens there was hardly any material at all. In other screens there was a lot of bone flakes visible or other larger items.

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I could see in one of the screens that a Parahippus toe bone (phalanx) had somehow slipped past the person digging their grid square back in 2011 and ended up in the sandbag instead of in the plastic bone bag with the rest of the finds. Along with any micro-fossils found in the concentrated washed micro-matrix (rodent teeth, bird bones, lizard bits, etc.) the larger pieces will finally be added to the collection having spent a few years resting in a sandbag in a pile. Art showed me one other macro-fossil he had just recovered from the last sandbag he had just processed--a hoof core from one of the little 3-toed horses. This is the reason for bagging all of the matrix--no specimens (big or minuscule) get left behind.

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Tomorrow I'll be back for Day 2 of my Thomas Farm adventure. I'll likely be working the square behind where I was working today--leveling that so that we have access to all sides of the horse leg bone so we can give that one a plaster jacket and remove it from the square. More tomorrow night.

Cheers.

-Ken

Edited by digit

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caldigger

Maybe you kids on the other coast will have a dry summer this year, since you seem to be having so much rain over the winter months.

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jcbshark

Good luck out there Ken, nice finds: )

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digit

A good day in the field. Not spectacular finds for Thomas Farm but (with the exception of the gator osteoderm) not things you'd tend to find in the Peace River (and certainly in better--but more fragile condition). It's also from the early Miocene (~18mya so Burdigalian) which is older than the Plio-Pleistocene stuff we find in the Peace. I think we occasionally get some Miocene in the Peace but I think is from the younger end of that epoch.

Heading out from my hotel room this morning. I'm moving hotels today as I realized I'd be closer if I stayed in Alachua rather than Gainesville. I think I'll start my morning by helping out with some screening of the matrix before moving down into the dig site for another fun day with screwdriver and dental probe.

Another update tonight.

Cheers.

-Ken

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ynot

Looks like Y'All are off to a good start!

:popcorn:

Tony

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digit

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My wife suggested I start off with this as I got skunked even more than my meager finds yesterday. Just to be clear--there are lots of fossils in the sinkhole at the Thomas Farm site--they just don't seem to be in the square I'm working. To give you an idea of how crazy dense the fossils can be, here is my friend Cindy's square:

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The edge of the new area we are working (which has been under tarps for several years while the other section was dug down) seemed to have a fossil dense area. Everywhere Cindy dug more bone fragments popped up.

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We're waiting for Dr. Richard Hulbert to make it out to the site so he can give some guidance on this mass of bones. There are (as of now) no skulls or complete important looking bones--mostly broken-up pieces, but lots of them. The area is really too big to make a single large jacket for all of this assortment of bones. Dr. Hulbert would easily be able to make the call as to what bones could be pulled out and bagged to allow a trench to be dug around the rest so that a reasonable size jacket could be placed to get the rest out.

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digit

My task for the day was to move to the square adjacent to the one I worked on the first day and lower the level of that square to match the level I had brought yesterday's square down to. This is what my new square looked like at the start of the day.

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The piece of rug (under the screwdriver to the left of the white bucket) is where the horse leg bone is located awaiting the surrounding material to be removed so a jacket can be made and this specimen can be removed. This square is at the edge of the working area and you can see my blue bucket with the sandbag sitting in it on the lower level to the right. This lower level is a drainage pathway down to the sump pond about 100 feet away at the other end of the dig site. Rains last week have made this area still quite sticky (hence the carpet squares to keep from standing in mud and tracking it all around.

The task is to bring the level of this square down to the level of the square to its left (where I worked yesterday). You'll notice in back of the white bucket is a smaller square of taller material. A small jacketed specimen was removed from the middle of this square last week and for some reason this section was left high and proud from the rest of the square. More material for me to work through. Before I show my day's progress on this task let me show you the two finds that were not insignificant bone fragments--yup, I said two.

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The first is a broken Parahippus molar. I didn't immediately recognize it when it was revealed covered with clay. the long tapered point on one end seemed odd. It wasn't till I realized this was a complete root and that the item was a tooth that it all made sense. Looks a bit nicer cleaned up but still is only a partial tooth. The other piece is a mystery but I'm assuming may be something like part of a turtle plastron (lower shell). When I first came upon it I thought it might be another gator osteoderm (upside down) but it looked a bit too square. It turned out to be a thin section of bone that did not resemble an osteoderm on the back side.

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digit

While removing matrix material from this square I started on the lower half of the square in the picture below. The top layer was a few inches of clay--with gray and yellow banded layers within the larger clay stratum. It formed a rather loose attachment to the sandy layer below it and so when it was removed formed a rather clean smooth surface once the overlying clay had been removed. You can see I've moved the purple kneeling cushion off to the side and exposed the damp toilet paper layer that is protecting the horse leg bone diagonally through yesterday's square and impinging upon the edge of today's square. I would occasionally work this square from the right standing below the square and using my blue boat cushion to lean one hip against the wall while working the right half of the upper section of the square.

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Once I had a lot of the clay layer removed from the bulk of the square, I focused on the tall smaller square of matrix along the top edge. Over time I managed to nibble this down to near the level I needed to match the adjoining square. I've got about one more hour or so of work to finish off the clean-up of this square so that it is at the level I need it to be. Then the horse leg bone will be able to be jacketed and removed. After this, I plan on moving over to another square (possibly one with some fossils). ;)

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digit

I did take some time out of my busy day leveling a square (and filling 5 sandbags with matrix) to learn how to wash the matrix to remove the clay and sand and reveal the micro-gravel and micro-fossils. The matrix is dumped into a 5-gallon bucket and allowed to hydrate by topping it off with water. The first step is to use a wooden stake like a paint stirring stick to try to mix the wet matrix into a relatively even slurry. This is then poured into the smaller sifting screen with the 1/4" mesh sitting atop the larger sifting box with the finer window screen.

Care must be taken not to overload the screen and to rinse it out well so it doesn't clog-up too much. More water is added to the bucket and it is stirred again to loosen-up the matrix toward the bottom of the bucket. When all the matrix has been dumped into the upper sifting screen and the bucket rinsed out then the hose is used to break down any last clumps of clay and make sure as much material as possible makes it through the top coarse screen. Any bone bits visible in the upper screen are moved to join the finer grit in the lower screen. Some final washing of the material in the fine screen to remove the last of the clay completes the washing phase. The screen boxes are then taken out to rest in the sun so that heat and airflow will dry out the residual material making it easy to bag up.

The first of a handful of bags of matrix I washed turned up two little fossils that got by the person who bagged this matrix. The first is a nicely complete small artyiodactyl phalanx and the second is a piece of jaw (or possibly skull) with two teeth still in situ. These fossils had waited patiently in that sandbag since 2011 to be revealed (and, of course significantly longer in the ground).

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Day 3 tomorrow and I'm still excited to go back out. Will be doing a bit more matrix washing and hoping to complete the work on today's square so I can move onto another square and maybe find some interesting items to make for some fun postings.

Cheers.

-Ken

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ynot

Hey Ken,

At least You got to find some nice things in the bags.

Wondering what Tammy is finding while You are getting a little skunk?

Tony

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digit

Tammy has always been my better half (and smarter too). She had work obligations and so didn't join me on this trip so I'm having all the fun moving mountains of matrix and getting skunked for finds and she's laughing at me during our evening skype calls. We'll probably make one last trip to the new Montbrook site together before the dig operations wrap for this season.

Cheers.

-Ken

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digit

So here's today's update--day three of five completed. On the first day I found two Parahippus teeth, yesterday I found one Parahippus tooth, today zero Parahippus teeth. By tomorrow it looks like I'll owe them one if this trend continues. Yesterday's findings were meager--today (though I did not think it possible) they were less. Other than a few small bone fragments I found one crumbly alligator osteoderm in all my digging--not a hugely productive day for science.

I started the day screen washing some more bags of matrix (from 2010 and 2011). I got down to the dig area at around 9:30am and dug pretty much straight through with breaks only for drinks and to carry bags of matrix up from the digging area. By about 2:00pm I was able to complete the last of the matrix removal from square 13N x 1E to flatten its surface to the level of the adjoining square--about 8 sandbags full of matrix. Doesn't look like much when it is sitting in the square but it seems to add up.

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When I was done the square was flat and clean save for the toilet paper--uh, make that Paleo Tissue--covered Parahippus leg bone in its completed pedestal. Cindy and I spend a few more minutes accentuating the undercut at the base of the pedestal to make sure it would detach easily once the jacket was in place. We then pulled off the old layer of toilet paper that I had been using to protect the clay on the top of the pedestal from drying out, shrinking and cracking. We replaced the old paper with some fresh layers of 2-ply squeezably-soft "paleo tissue". I then used a whisk broom dipped in water to spritz the paper to dampen it enough so that it could be pressed down to remove any air gaps between it and the fossil below. A few more layers were added where we could see through to the fossil below. This is the only thing separating the bare parts of the fossil on the top of the pedestal from contact with the plaster from the jacket so this is both important padding as well as a means to keep plaster from sticking to the fossil (which would be a mess).

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After the wetted toilet paper was in place we ripped strips of gauze to the lengths we needed for the jacket. The gauze we use is medical grade material designed for constructing casts to immobilize broken limbs. It comes pre-impregnated with plaster which is activated by a quick dip in the water followed by a gentle squeeze to wring out the excess. The strips were then stretched out and smoothly wrapped around various portions of the fossil pedestal. Several layers overlapping at different angles are used to build up the jacket with care taken to make sure it is pressed down so no air bubble voids were created which could cause the fossil within to shift or could form weak spots in the jacket. When we were done adding layers and smoothing out the plaster, the gleaming white jacket looked reasonably professional.

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digit

Once we had the jacket complete I made up a collection label for the specimen. These are the same types of labels we make for our other finds (and also to identify where the bags of matrix came from when they are opened later and washed to separate out the micro-fossils). The information is filled-in on pre-printed slips of paper and sealed into small zip-top bags.

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This protected label is then attached to the plaster jacket in a simple and permanent way--with a couple more strips of plaster gauze. This information can then be accessed when the jacketed specimen is being prepped by simply cutting the bag open and retrieving the slip of paper. As some of these jackets may have to wait years before there is time to prep them, it is important for data management that the tags are secured so they cannot be separated from he fossils and lost.

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At the end of the day (4:30pm) the jacket was still cool to the touch so we knew the plaster was not fully cured. Had we been able to jacket it earlier in the day when the sun was beating down on that square at midday, the jacket would certainly have cured within an hour or so. As it is, it will have to wait till tomorrow before it has reached its maximum strength and we can pop the jacket from its base. There is a slight chance of overnight rain showers so we pulled a super sized tarp over the entire working area and secured the corners with sand bags (we have a lot of those). Tomorrow I'll use a small shovel and a hammer to release this jacket and I'll move on to a new square (hopefully) with a few more interesting fossils than the areas I've been working so far. Fingers crossed.

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Cheers.

-Ken

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ynot

Very nice report, and it will be hard to find any less tomorrow!

Hope Your luck turns for the better!!

Tony

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digit

This would be the point in the made-for-TV movie that the hero (that's me by the way) pulls off an incredible turnaround and snatches victory from the jaws of defeat. My life is often like some weird independent film so who knows--I could get lucky in the end and ride off into the sunset with my best girl at my side.

I was telling Cindy this afternoon that my knick name should be 'steamroller' because I'm good at flattening the squares. Now I just have to get better at finding fossils. Actually, there is really very little skill involved in finding fossils while digging here--only skill in not destroying fossils when you do come across them. It really comes down to what's in the square you are working. There's about as much skill in finding fossils here as there is in playing slot machines--they both pay off when they are ready and not before.

On the plus side, I've now got my Junior Jacketeer merit badge--So I got that goin' for me, which is nice. (obscure Bill Murray Caddyshack quote).

Hoping for a change of luck tomorrow.

Cheers.

-Ken

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digit

Here's my update for day 4 of 5 at the Thomas Farm dig site. Today brought a welcome change with Dr. Richard Hulbert joining us at the site. Dr. Hulbert had planned on being here all week but was unavoidably detained by another dig site--the new Montbrook site. It seems that last week a complete lower jaw of a gomphothere complete with teeth intact. This was sitting under one of the squares nearby the ones we were working when we were at Montbrook a month or so ago. We likely walked directly over this remarkable find several times each day--you never know what's just under the surface. Dr. Hulbert believed the upper maxilla and skull might be found nearby and he was right as that was recovered from the site early this week.

This morning someone had remembered to retrieve the box with the articulated resin casts of various horse fossils from one of the cabinets on site. Since Parahippus leonensis and to a lesser extent Archaeohippus blackburgi are some of the most common fossils found at the Thomas Farm site, they have resin replicas on hand as examples and training aids.Many of us had been finding jaws, teeth, and foot components of these two species in our squares so having these articulated models to envision how our parts fit into the whole is a useful visualization tool. I took a moment this morning before we got started to take some photographs of the more robust Parahippus and more slight Archaeohippus articulated legs. Looking at the casts it is plain to see why these are called 3-toed horses. There was also a skull and mandible (in two halves) of a Parahippus which was more complete than most of the mandible pieces we've been seeing while digging at the site.

Here are the Archaeohippus (top and right in the comparison photos) and the Parahippus leg reconstructions. You can see how the central toe is the one that bore the weight of the animal. Later in horse evolution (e.g. Equus) the two vestigial toes disappeared completely leaving the single hoof that we come to associate with horses (and related kin like zebras, donkeys and the like).

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The skull--and in particular the mandible--are interesting to see in a complete state as most of the pieces we see are fragmentary.

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It was great (as usual) to have Dr. Hulbert on site. He is a walking Wikipedia of vertebrate paleontology knowledge. And as the collections manager for the museum he is invaluable to have onsite when trying to figure out how to proceed during the dig. My friend Cindy had been dealing with an embarrassment of riches grid square that peppered with a cluster of fossil bits that made figuring out how to continue digging rather troublesome. Within minutes Dr. Hulbert took stock of what Cindy had uncovered and deduced that most of the material was from the two horse species that dominate the fossil finds at Thomas Farm. At other sites each and every piece would likely be carefully extracted and preserved. The museum has over 20,000 specimens already from these species and so only more rare or better preserved specimens are kept for these common species. With such an extensive collection already they can afford to simply remove lesser quality (partial) or more common bones in order to get access to (and create jackets for) more unusual finds.

Dr. Hulbert quickly identified a large leg bone of a camelid and a vertebra that were worth jacketing for later preparation. He was able to make the executive decision that we could not of which specimens to give special attention to and which to just carefully dig up and bag all the pieces. This kept Cindy (and Dr. Hulbert) busy for the rest of the day clearing out lots of bones from this square.

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When Dr. Hulbert arrived in the morning I informed him of how my previous three days had been going (largely uneventfully) and he was surprised that I had landed on such unproductive squares. I told him about working the largely clay-filled and largely unproductive squares around the horse leg bone that was in my square from the previous week. He mentioned that he doesn't usually consider horse leg bones (of which they have enough to build a fleet of horses) interesting enough to jacket. He said they would use that less valuable jacketed specimen to train some new preparators with so that it wouldn't be a great loss if they screwed it up. Dr. Hulbert used a trowel to pry under the jacket and pop it off the square. This is the only evidence that something was ever there--kind of like negative space in a painting.

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We found me a new square to start digging in (a couple down from where I was on the first three days). This one didn't appear to have as much clay and when we pulled off the four small carpet squares that were protecting the surface (so we could walk on it with minimal impact) we could see a wad of toilet paper covering something in the middle of the square. We peeled off the paper to see signs of several crushed brown bone fragments. Hard to tell what was being marked there but at least there was something in the square to look forward to digging up.

I progressed from one edge of the square dropping the height down to the prescribed level. It didn't take too long to find my first complete bone (phalanx) though I can't seem to match it up exactly with either of the two horse species--which are the odds-on favorites for any supposition of the species for any fossil found here.

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I soon spotted the shiny dark brown coloration that signals the first indication of a buried bone in the area. At first I could only see just the corner and suspected it might be a broken end of a long bone. The more I probed with the dental pick I realized this might be larger than I originally thought. I started gently pulling off the clay layer in which this bone was encased. The bone was exceedingly fragile and liked to flake away as the clay matrix was removed. When I could see this was a much wider bone than the long bone I'd originally supposed, I called over Dr. Hulbert for his opinion. He could see from the hint of the vague outline that I'd already uncovered that it was likely a scapula (shoulder blade) from a Parahippus horse. He said if he was correct that there would be a thin neck on the one end with the concave connection to the upper leg bone (humerus). Dr. Hulbert mentioned that these scapulas are very thin and brittle and that they do not tend to come out in anything near one piece but that the thick end where it attaches to the leg would probably hold together reasonably well. My instructions were to just back all of the pieces in a smaller zip-top bag and put that in the larger bone bag.

I started working out the outline and working in from the outside till I met the edge of the bone. I found the socket end--called the glenoid cavity--and indeed it appeared more sturdy than the crumbly remainder of the scapula. Once I had it outlined (more for my photos than anything else) I was able to slip a trowel under it and lift out the entire scapula as more or less a single entity. This would likely crumble with further handling so I slipped it into its bag--to keep its bits segregated--and slid this bag in my bone bag.

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Most of what I found today in my (finally more productive) square tended to be horse--mainly Parahippus. I did, however, recover a few nice specimens from a much different beast--Alligator olseni. I'd found several gator osteoderms here at Thomas Farm as well as at the Montbrook site (though those were bone white instead of dark chocolate brown). The little osteoderm--about the size of a nickel--popped out of the matrix while digging. It seemed pretty well ossified and wasn't crumbly like many that come from here. All it needed was some gentle cleaning to reveal its beauty.

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A little while later a tooth revealed itself. At first I thought it might be a canine tooth but closer inspection revealed that it was likely a small gator tooth with a nice long root.

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The next solid bone I encountered I thought might be broken due to the straight sides along one face and the overall odd shape. Dr. Hulbert was quickly able to confirm my suspicion that it was in some way part of a horse leg (those bones are well ossified and fossilize in good shape). He said it was one of the bones in the wrist/ankle joint of the horse--a tarsal bone and that despite its odd appearance that it was complete. It's so nice to get a definitive answer quicker than I would be able to look up the information online or in a book.

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