Updates from the Vertebrate Paleontology Lab

New Carmel Church tooth

Thu, 4 Feb 2010 13:22:24 -0500

During Dino Day, I had a small army of volunteers prepping various materials in the lab, including the bagged material from last August’s Carmel Church excavation. During the course of the day they managed to get through several bags of material, which as usual were mostly shark teeth. Everything was laid out to dry, and yesterday I finally had a chance to look at the material.

I was amazed to see the tooth shown at the top mixed in with the other remains. This is a small tooth with an enormous, swollen, laterally compressed root. There is actually a tiny enamel crown, visible in this closeup:

This appears to be a lower anterior tooth from a beaked whale, from the family Ziphiidae. These are among the rarest of the rare; only two possible ziphiids have been reported from Virginia (Whitmore and Kaltenbach, 2008), and two additional specimens from Maryland, although one of these is a cast of a privately-held specimen (Fuller and Godfrey, 2007). Whitmore and Kaltenbach (2008) also reported a total of 15 fragments from Lee Creek Mine. All the Lee Creek specimens are Pliocene; the two from Maryland are Miocene, and the Virginia specimens could be anywhere from middle Miocene to late Pliocene. Only two of the Lee Creek specimens included anterior teeth, as shown below (Whitmore and Kaltenbach, 2008, Figs. 43 and 44):

While these teeth have some features with the Carmel Church tooth, they aren’t particularly close matches (nor is “b” above, a modern specimen of Tasmacetus shepherdi). In fact, it seems that very few anterior teeth from beaked whales have ever been found, and this may be the first one from the middle Miocene. There was a beaked whale recently described from Peru, Nazcacetus urbinai, that was from the same time period as Carmel Church and had enlarged anterior teeth, but the teeth themselves were not preserved (Lambert et al., 2009). The socket for the anterior tooth in Nazcacetus is about the same size as the root of the Carmel Church tooth. The Nazcacetus type is shown below, before it was completely prepared:

With such limited material for comparison, it will be difficult or impossible to determine which species this tooth represents. Even so, it’s an exciting and surprising discovery for Carmel Church. It also shows promise for the material we’ve already collected, since better than 80% of the material recovered from Carmel Church so far has not yet been prepared or closely examined.

References

Fuller, A. J. and S. J. Godfrey, 2007. A late Miocene ziphiid (Messapicetus sp.: Odontoceti: Cetacea) from the St. Marys Formation of Calvert Cliffs, Maryland. Journal of Vertebrate Paleontology 27:535-540.

Lambert, O., G. Bianucci, and K. Post, 2009. A new beaked whale (Odonticeti, Ziphiidae) from the middle Miocene of Peru. Journal of Vertebrate Paleontology 29:910-922.

Whitmore, F. C. Jr. and L. G. Barnes, 2008. The Herpetocetinae, a new subfamily of extinct baleen whales (Mammalia, Cetacea, Cetotheriidae), in C. E. Ray, D. J. Bohaska, I. A. Koretsky, L. W. Ward, and L. G. Barnes (eds.), Geology and Paleontology of the Lee Creek Mine, North Carolina, IV. Virginia Museum of Natural History Special Publication 14:141-180.

More plants

Tue, 2 Feb 2010 14:10:20 -0500

With a book chapter, Dino Day and an exhibit opening behind me, hopefully things will settle down a bit and I can actually work with some fossils; I was beginning to wonder if that was still part of my job!

We have two paleontology collection storage rooms here at VMNH, with a total of over 120 cases plus oversize shelves (there’s an additional room for unopened jackets). Invertebrate fossils (except insects) are stored in one room, while the other holds vertebrates, insects, and fossil plants. We actually have a fair bit of expansion room in the VP/Paleobotany cases, which we reserved in anticipation of additional collections from Carmel Church, Solite, and Wyoming. But as it turns out, a number of those cases are being filled from an unexpected source: Carboniferous plants.

Between Tom McLoughlin’s fantastic fossil plant donation last year, and two trips to the Boxley Quarry in Beckley, WV, we have quietly almost doubled the size of our paleobotany collection. Among the material Boxley delivered for Dino Day were numerous large specimens of lycopsids, including several Sigillaria like the one at the top. There were also several examples of Lepidodendron:

The great thing about these acquisitions is that Carboniferous plants were underrepresented in our collection; the bulk of our specimens were Triassic in age (due to our extensive collections from Solite and other Newark Supergroup localities). So we weren’t just increasing the size of our collection, but filling a significant gap as well.

We’re currently in the early stages of trying to organize and catalog all this material, and we anticipate more specimens from Boxley over the next year. Expect to hear more about this material in the coming months.

New dinosaur jacket

Wed, 27 Jan 2010 09:07:26 -0500

Having completed our Diplodocus scapulocoracoid, during Dino Day last Saturday we opened a new dinosaur jacket. This appears to be a somewhat crushed sauropod right femur (thigh bone). You’re looking at the posterior surface, with the proximal end at the left and the distal (knee) end at the right (the distal end is poorly preserved). The bulge near the middle is the fourth trochanter, a muscle attachment point. The large light-colored patches at each end are gypsum deposits, which need to be removed. Compare the shape to this Apatosaurus mount from the Sam Noble Oklahoma Museum of Natural History:

I’m not sure yet what taxon our specimen represents. It’s a pretty small femur (length is about 134 cm). We have found Camarasaurus, Apatosaurus, and Diplodocus at the same site.

I’ll have more updates as the preparation progresses.

Dino Day 2010

Sun, 24 Jan 2010 10:34:26 -0500

VMNH’s Dino Day festival was held yesterday. The day started off early with the installation of a new exhibit case. One of our volunteers, Mike Morriss, owns Imageworks, a cabinetry manufacturer in Chester, Virginia. Imageworks is constructing and donating two beautiful cases to the museum, each large enough to hold a decent-sized whale skull. Mike and his family delivered and installed the first case yesterday (above). Here’s the completed case with the skull of “Sinistra”, our Carmel Church Diorocetus, on display:

Boxley Materials was also on hand, to give away samples of fossil plants from their Beckley Quarry. Charles Craddock and several other Boxley employees spent the entire day manning the table, handing out specimens and answering questions (this picture was taken before we opened to the public; one we opened the doors it was hard to see this table for all the kids packed in front of it):

There were two lectures on Saturday. DorothyBelle Poli from Roanoke College spoke on plant evolution, while I spoke about the injuries to “Sinistra”. After the last lecture, we opened a jacket containing a dinosaur femur (somehow, I didn’t take any pictures of it on Saturday, but I’ll post on it next week).

I’d like to thank all the volunteers who helped out in the lab on Saturday, including Brett and Tim Dooley, the Morriss family, Keith Degnan, Alana Dodd, Trell Martin, and Ward Littlefield, as well as the employees of Boxley Materials, for making Dino Day such a success.

“Messages from the Mesozoic” exhibit open

Fri, 22 Jan 2010 21:51:36 -0500

Last night we had a members’ reception at VMNH to mark the opening of a new temporary exhibit, “Messages from the Mesozoic”. The centerpiece of the exhibit is a mounted cast of Acrocanthosaurus atokensis, on loan from the North Carolina Museum of Natural Sciences. A number of specimens from our Wyoming excavations are included in the exhibit, including these Stegosaurus bones:

There are several Triassic-themed displays, since pretty much the only fossiliferous Mesozoic rocks in Virginia are from the newark Supergroup. Several bones from Agnosphitys are displayed, as well as this life-size model phytosaur:

We also have several theropod tracks from the Triassic deposits in the Culpeper basin in north-central Virginia:

The public opening of “Messages” will be during Dino Day tomorrow, and it runs until September 18, 2010.

Back to Beckley

Fri, 15 Jan 2010 07:40:01 -0500

I spent yesterday in Beckley, WV at the Boxley Materials Quarry there. Boxley is donating two truckloads of Pennsylvanian New River Formation to the museum for Dino Day. The material is loaded with fragments of plant fossils, and we’re going to give them away to children during the event (after withholding the best material for the museum collection):

I’d like to thank Boxley for their generous donation, and especially Paul Witt, Stacy Barbour, Greg Jones, and Charles Craddock (left to right, at top) for helping us get this event organized.

Diplodocid scapulocoracoid - almost finished

Wed, 13 Jan 2010 10:41:12 -0500

On Dino Day two years ago we opened a jacket from Wyoming containing a diplodocid scapulocoracoid. It has been a relatively low priority specimen for us (in terms of the urgency to complete preparation), but we’ve slowly been working away (see various updates from 23 March 2008, 1 September 2009, 16 September 2009, and 10 November 2009). We’ve had an increasing number of volunteers working in the lab. As they’ve become more comfortable with fossil preparation, the work pace has picked up.

This morning we finished preparation of this specimen. At this point all that remains is to complete the second half of the storage jacket (see a video on making a storage jacket). We’ll probably start that today, and finish it next week. If all goes according to plan, we will open a new dinosaur jacket during Dino Day on January 23.

New and upcoming exhibits and events

Fri, 8 Jan 2010 08:49:31 -0500

Usually March to October is my busiest time of year, since that’s when I’m in the field, but this winter has been kind of a whirlwind. Besides writing deadlines, I’ve been involved in the planning for several exhibits and events.

Each year we have a “Dino Day” paleo-themed event at the museum (here are the 2008 and 2009 Dino Day posts); this year’s Dino Day is January 23rd. I’m presenting a public lecture about the Carmel Church Diorocetus (now named “Sinistra”), and we’re hoping to open a new dinosaur jacket.

The same week we’ll be premiering a new exhibit, “Messages from the Mesozoic”. We’ll display a number of cast skeletons, both from our collection and loans from the North Carolina Museum of Natural Sciences. We’ll also have Newark Supergroup trackways, some of our Wyoming specimens, and Agnosphitys material in the exhibit, as well as a Cretaceous log from northern Virginia (shown above). There is a reception for museum members on January 21, and the public opening will be during Dino Day. It’s scheduled to run until September 18.

We also installed a new exhibit case just before Christmas. One of our exhibit halls is called “Uncovering Virginia”, and includes displays on six localities in the state (including Solite and Carmel Church). The oldest site represented in “Uncovering Virginia” is Carboniferous, but that leaves almost the entire Paleozoic unrepresented in the exhibits. The new case features 36 Virginia specimens from the Cambrian through Devonian (plus a Proterozoic dropstone):

If you can get to Martinsville, try to stop by on the 23rd for the Dino Day events and all the new exhibits.

From the collections room (Balaenula)

Sun, 3 Jan 2010 13:41:43 -0500

This is more fallout from my forthcoming paper on the fossil vertebrates of Virginia. There are extensive Pliocene marine deposits in Virginia, particularly along the James and York Rivers. The Yorktown Formation, particularly its oldest member (the Sunken Meadow), has a fair number of vertebrate remains that have so far not been extensively described.

Right whales (family Balaenidae) are one of the more interesting types of animal found in the Yorktown Formation. Right whales have a fossil record going back to at least the Early Miocene in other parts of the world, but so far have not been reported earlier than the Pliocene on the Atlantic coast of North America. But in the Pliocene of Virginia they may be the most common type of baleen whale.

As far as I can tell, the most commonly collected balaenid remains in the Yorktown are tympanic bullae. These are very distinctive in balaenids, as they are rather dramatically compressed when compared to balaenopterid or cetotheriid bullae.

According to Whitmore and Kaltenbach (2008) two genera of baleen whale are known from the Yorktown Formation in North Carolina. The more common is Balaenula, a small extinct genus, and we have at least two of these in the VMNH collection, both from Surry County (top and below):

Westgate and Whitmore (2002) also described Balaena ricei from the Yorktown Formation in Hampton, Virginia (this is the same genus as the modern bowhead whale). There were no tympanic bullae described with this specimen, but Whitmore and Kaltenbach (2008) referred two of the balaenid bullae from the Lee Creek Mine in North Carolina to Balaena (they referred 13 bullae from the same site to Balaenula). In part, the basis for the referral to Balaena was the larger size when compared to Balaenula.

In the VMNH collection, we have at least one balaenid bulla, from James City County, that may represent Balaena:

This specimen is about 10% larger than the largest Balaenula specimen from Lee Creek Mine, but still quite a bit smaller than modern Balaena. It does, however, demonstrate the presence of at least two right whales in Virginia during the Pliocene.

See this archived post for more information on cetacean tympanic bullae.

References:

Westgate, J. W. and F. C. Whitmore, Jr., 2002. Balaena ricei, a new species of bowhead whale from the Yorktown Formation (Pliocene) of Hampton, Virginia, in R. J. Emry (ed.), Cenozoic Mammals of Land and Sea: Tributes to the Career of Clayton E. Ray. Smithsonian Contributions to Paleobiology 93:295-312.

Whitmore, F. C. Jr. and J. A. Kaltenbach, 2008. Neogene Cetacea of the Lee Creek Phosphate Mine, North Carolina, in C. E. Ray, D. J. Bohaska, I. A. Koretsky, L. W. Ward, and L. G. Barnes, eds., Geology and Paleontology of the Lee Creek Mine, North Carolina, IV. Virginia Museum of Natural History Special Publication 14:181-269.

Happy Holidays

Wed, 23 Dec 2009 13:11:55 -0500

I had intended to take a short trip to northern Virginia this week, to look at Ordovician and Devonian rocks in the Winchester area. The east coast snowstorm put a damper on those plans; I’ve had to dig fossils out from under snowbanks before, and it’s not an experience I’m eager to repeat. Instead, while technically on vacation, I’m at home trying to finish my book chapter before the end of the year.

The images I’ve included in this post have nothing to do with paleontology, but they do present a bit of a geological mystery appropriate to the season. About two weeks ago we had a hard overnight frost in Martinsville. The image at the top is the view through my truck windshield, of the ice crystals that formed on the glass.

Zooming out a bit, you can see that there were actually two types of ice crystals:

Zooming out even more, the real weirdness is apparent; the regions covered by the two types of crystal are defined by the sweep of the windshield wiper blades, with the large crystals covering the area swept by the blades and the small crystals occurring in the unswept areas:

What’s even stranger is that I had not used the wipers in days. My assumption is that the varying amounts of dirt on the different parts of the windshield caused this variation. Perhaps since there was more dirt on the unswept areas, there were more nucleation points for crystals to form, resulting in less room for each individual crystal. I’m not sure about this (mineralogy was not my strongest subject!), so if anyone has an alternate hypothesis feel free to post it in the comments.