Recently in Prehistoric Life Category

Today was, as it turned out, a great day! I got to go out to a region of the Grand Staircase-Escalante National Monument that is noted as something of a "bone yard". But, as I would soon learn, there was more to the place than just bones. Clams, petrified wood, turtle shells, and even a live reptile. The rocks, sandstones and mudstones were from a period over 80 million years ago in the Late Cretaceous. What is now southern Utah was a land of rivers, streams, and swamps, inhabited by creatures like Parasaurolophus, Gryposaurus, and Troodon.

Clicking on the thumbnail will open up a nine image Flash slideshow with photos from the day's trip. (Click on the "i" info button to learn about the photo.)

I've put in a lot of time recently, even on my "days off", on work related projects - I think I've mentioned (too lazy to go back and look) that I've been shooting a lot of video that is destined for the park's first self-produced video podcast. Most of the shooting is done - just a few seconds of my mug on screen is all that is left in that regard - then a little additional editing, and that project will be complete. Did I mention it will be about Utah Prairie Dogs?

We also have some other ideas - Glacier NP seems to be something of a leader in this regard, so they're not original ideas - for virtual tours and hikes that I'm working on, too. Problem there is that rather than be video they'll use Flash and, while I have a piece of software that allows me to produce Flash "movies" (like on the opening page of my website), it chokes and crashes badly when I try to do something more complex. So that means that I'm going to have to learn to use the actual Flash program and will be investing a lot of time in that over the next several days.

This past Friday and Saturday was the park's 2nd annual Geology Festival and the guest speakers each night were paleontologists. That was cool stuff! Friday night we had Dr. Alan Titus who is the chief paleontologist for the Grand Staircase-Escalante National Monument and he talked about Deinosuchus. What a croc! They found a skull fragment last summer - though known in other places, a first for Utah - and this thing was a monster. The complete head would have been close to 2 meters (6+ feet) and the sockets for the largest teeth were 5 cm (2 inches) at the base (the teeth would have been about 15 cm/6 in. long). Total body length of this creature would be on the order of 10 meters or 33 feet, and it ate dinosaurs for lunch! Here's the other scary part: These crocodiles evolved in the late Cretaceous at a time when there was extensive volcanic activity, high CO2 levels in the atmosphere, and the ice caps melted raising sea levels. Let's hope climate change doesn't cause a repeat in crocodilian evolution.

The other speaker was Jeff Bartlett, Director of Collections and Research at the College of Eastern Utah's Prehistoric Museum, and the topic was recent findings in Utah. The highlight of his presentation was the fossils he brought with him. In addition to several bones, he brought along a trackway and a coprolite. Last fall I wrote about some of the trackways out in the Grand Staircase (here and here), but the one he brought along had been removed from the bedrock and was amazing in that some poor gar-like fish had been in the wrong place at the wrong time. Remnants of the fish, in the form of scales, were embedded in this dinosaur's track! I have some coprolites in my collection of fossils - if you remember, coprolites are fossilized "poop" - but nothing like what we saw Saturday night. He showed a photograph of a very large coprolitein the presentation and what he brought was a fragment (measuring about 15 x 10 cm/6 x 4 inches) of this much larger piece - and this thing contained bone fragments! This chunk of fossilized excrement came from a freakin' carnivore that was roaming around (what is now) Utah in the Cretaceous!

At times, avian activity seems to be slowing down some around here. I'm not seeing as many of the migratory breeding species like Western Tanager and, oddly, I haven't seen any of the tanagers with young in tow, either. I did see a Dark-eyed Junco the other day being followed around by a cowbird chick - ugh!

Several weeks ago I had the chance to go digging around in the Tropic Shale for Cretaceous fossils and came back with a pretty good haul of shells, snails, and ammonites. Today I got to visit another area in the Tropic and came back with more cool stuff! In this first image are two shark teeth along with one from a ray. The shark tooth on the right measures over 3 cm. (1.18 in.) and is the largest of the 36 I collected - most of them only about .64 cm. (about 1/4 in.). The ray tooth is about 1.5 cm. ( 0.6 in.) and the largest of 7 that I found.

These are pretty cool, too: Fossilized jawbones fragments from some kind of fish from the period. The smaller fragment still contains a tooth and, in the larger fragment you can see where the teeth have broken off when looking at it from the top.

Unlike my last "expedition" where it was sometimes necessary to use a rock hammer to break apart pieces of rock, this time all I did was look around on the ground (on my hands and knees!). Once I knew what I was looking for, the teeth would really stand out against the normal rock. It wasn't like they were just lying around for the taking, either, as it did require some diligent searching. Included in the day's take were some assorted fish bone fragments and a vertebrae as well as a few pieces of coprolites (that would be fossilized, um, fish poop), and some pieces of sandstone with ammonite impressions embedded in them.

It was all great fun, though now my knees are a little sore!

The past couple of days here have been miserable. Snow on and off all day yesterday, the value of today's highest wind gust (41) exceeded the value of the day's high temperature (35). Though I would have rather been out chasing birds on these final 2 days of my "break in service", I spent them playing Junior Invertebrate Paleontologist, instead. Yesterday I gently cleaned everything up then, today, got them all identified. I thought I would share some of the incredible detail on a few of them, too.

This first example is a straight ammonite named Sciponoceras gracile; straight ammonites are members of a family known as Baculites. Extinct, Baculites ranged from 7 cm (2.75 in.) to 2 m (6.5 ft.) in length, but the fossils are extremely fragile and rarely found intact. This fragment is 2.5 cm (1 in.) long, 1 cm. (0.4 in.) in diameter and is interesting because of the markings. The lines that you see are called sutures and divided the shell into chambers. Similar in some respects to the ballast tanks on submarines (I'm no expert by any means, but it is an easy way for me to explain this - even if not the correct scientific description), these animals could add/remove water from the chambers and thereby control their depth in the water column. Like all the other ammonites, Sciponoceras disappears from the fossil record 65 million years ago.

Perissoptera prolabiata, while extinct, is a member of a gastropod (snails and slugs) superfamily that includes modern conchs. Missing from this fossil is a "wing-like" extension that protrudes from one side. The attraction, of course, is the incredible detail that remains in the fossilized shell. Of the 3 I collected, this one exhibits much more of the shell detail and 1 still has the wing-like appendage (though little of the shell texture remains). Length is about 2.5 cm. (1 in.) and diameter (at the widest point) is 1.3 cm. (0.51 in.).

Another gastropod, Turritella whitei, was first described in 1893 by T.W. Stanton from the Tropic Shale. The fine detail in the coils around the shell are what makes this such a cool find (my last entry featured another one). Turritella species first appear in the fossil record in the Cretaceous and there are modern examples living today. This fossil is 3.5 cm. (1.375 in.) long.

Last we'll take a close look at a Pycnodonte newberryi. As noted in the last entry, these were all over the place at many of the limestone concretions. This one, at 2.5 x 2.0 cm. (1.0 x 0.79 in.), is not the largest I collected, but does feature a hole not found in the others. About 90 million years ago this oyster became a meal for a Gastropod that bored the hole then ate the tissue inside (then kindly left it for me to collect!).

fossiliferous adj. bearing or containing fossils; "fossiliferous strata"

I can think of no better way to describe the area I got to explore today with the director of the Bryce Canyon Natural History Association (the park's bookstore). Though we were outside of the park on private land, the Tropic Shale is one of the oldest sedimentary layers exposed within Bryce, and it is home to lots of fossils. The Tropic Shale are marine sediments that represent the period when the Western Interior Seaway (also called the Mid-Cretaceous Seaway) was at its greatest extent during the Cretaceous Period.

Mostly a dark gray dirt, I learned that you look around for "concretions" of limestone exposed as the dirt is carried down the hillside - this is where you look for fossils. These first 2 images are ammonites: cephalopods related to modern squids and octopi. The first is one with a coiled outer shell, the second with a slightly curved shell. Sometimes you find them just lying on the ground, sometimes they are embedded in the rocks. In the case of this second ammonite, I first found a rock containing the fossil's impression, then found the fossil itself after several minutes looking around in the rubble. An interesting fact about ammonites is that they are never found above the K-T Boundary: they became extinct at the same time as the dinosaurs 65 million years ago. The first measures about 5.25 cm (2 in.), the second 3.75 cm (1.5 in.).

Unfortunately I don't remember any of the exact names of the fossils I collected today (I have over 20 pounds of rocks and individual fossils), I'll be be getting all of that once I've had a chance to clean and sort. This is some kind of shellfish a Turritella species, a gastropod family that arose in the Cretaceous and still around today, measuring 3.2 cm (1.3 in.), very well preserved and still attached to the rock on one side. The rock that underlies the Tropic Shale is called the Dakota Formation and, across the highway from where we were working, radiometric dating determined the Dakota to be 93 million years old, making these fossils younger than that, but older than 65 million years. To me that is just amazing!

This is a small collection of some other examples; the three at the top are Pycnodonte sp., a type of extinct oyster. The first (left to right) is the outside top portion of the shell, the middle shows the inside of another shell, the one on the the right is the bottom part of a shell. The Pycnodonte are just everywhere - in one spot where I was standing there were thousands just lying there on the ground. These measure roughly 2.75 cm. (1.5 in.) On the bottom row we have another ammonite (4.25 cm., 1.75 in), a small clam (also 2.75 cm., 1.5 in.) and a gastropod - in this case a small marine snail type creature (2.5 cm., 1 in.).

All in all, it was a very interesting day (in the next few days I'll try to get the names and, when I do, I'll update the post).