Field of Science

Replacement for topozone? Not quite.

Back in May of this year Dinochick announced the demise of topozone.com, which was purchased by trails.com and not only no longer free, but also vastly changed. For years I had been using topozone to plot paleontological localities onto 1:24000 scale maps to print and found it indispensable (it could also be used to quickly change between coordinate systems and datums). ReBecca suggested the GeoPDF toolbar offered by the USGS and an accompanying program Map2PDF. This program turns Adobe Acrobat into a geospatial tool. Although ReBecca states that this program did not allow for plotting of coordinates, I found that it did such work, in a variety of coordinate systems and datums. The problem? Map2PDF is only free for a trial period and then must be purchased. Unfortunately the website does not list a price and you must contact a sales representative for purchase. In my mind this raises the big red flag "if you have to ask how much it costs you probably cannot afford it". Like ReBecca I miss the free and very useful topozone.com.

Recently, however, I came across another site that allows free access to topographic maps. TopoQuest.com touts itself as the replacement for topozone.com and was created specifically to be such a replacement. Excitedly I set to work and quickly found that I could access USGS DGRs (Digital Raster Graphics) of a variety of topograhic maps by imputing place names or even coordinates. Just like topozone.com, right? Wrong. Unfortunately I have not found a way to get the program to plot coordinates and print maps, and the website provides no contact information to contact the developer. I also noticed to my dismay that I could not plot sites in Arizona (where I am) using UTMs (my desired coordinate system) because the pull down menu only allows for northern zones, not southern. Still, if you are looking for a free program that will provide and search for DGRs, this may be the place. While it is still not a complete "replacement for topozone.com", the developer does state that the site is still under construction. Therefore I am keeping my fingers crossed that the ability to plot specific coordinates and print the resulting map will be added, or maybe that I just missed that available application.

Induan Dinosauromorphs?

A very cryptic news report and a somewhat clearer blog entry are announcing the discovery of presumably dinosauromorph fossils from the earliest Triassic (Induan) of Germany. Not too many details are given in the reports, but the fossils consist of bone fragments found in a quarry near Bernburg. Although the Early Triassic fauna is characterized mainly by temnospondyl amphibians and therapsids, crocodile-line archosaurs are present (Proterosuchus), but rare (Lucas, 1998). If these fossils are indeed referable to dinosauromorphs it would push the earliest appearance of bird-line archosaurs back from the Middle Triassic (Anisian) to the Early Triassic. This is not a completely unexpected, yet still surprising, find that will fill in some ghost lineages.

REFERENCE

Lucas, S. G. 1998. Global Triassic tetrapod biostratigraphy and biochronology. Palaeogeogeography, Palaeoclimatology, Palaeoecology 143: 347-384.

Polish Dragon

Despite needing to prepare for my first class lecture for my upcoming Age of Dinosaurs class which meets in less than a week, setting up for my kids (twins) 4th birthday party, and being behind on at least 12 manuscripts, reviews, etc.... I for some bizarre reason have decided to try my hand at blogging. Over the last year and a half I have for various reasons regularly monitored several blogs including SV-POW, Tetrapod Zoology, Dracovenator, and Dinochick Blogs and feel compelled to tackle such a chore myself in order to expend some, hopefully, creative energy. Obviously, given my background and employer my posts may deal heavily in Late Triassic paleontology; however, I hope to include posts on other subjects as I feel inclined. I realize that once I get started I will need to post somewhat regularly and hope to provide at least one post a week. I am also toying with the idea of having "guest" bloggers occasionally fill in when my creative energy is nil. Thus I hope that readers will check back from time to time and hopefully enjoy some of my offerings. The first is below.

This story has been bouncing around for about three weeks right now, the discovery of some significant fossil vertebrates from the Late Triassic in Poland. Dr. Jerzy Dzik and colleagues have announced the find of a large theropod and dicynodont from a quarry in Lisowice in southern Poland. What is very interesting about these finds are 1) the proposed age of the deposit, and 2) the proposed taxonomic affinities of the theropod. The deposit is believed to date around 205 +/-5 ma which would make it very late Norian or Rhaetian in age. This is significant given the discovery of the dicynodont, which are not only very rare in Laurasia, but believed (with the exception of a purported Cretaceous occurrence in Australia) to have fallen victim to an extinction event before the end of the Triassic. This find extends the range of Triassic dicynodonts more than 10 million years. As a Triassic worker I find this interesting because recent work by myself and colleagues Randall Irmis, Sterling Nesbitt, and Jeff Martz have found that the Late Triassic faunas of the Chinle Formation and Dockum Group of the southwestern United States remain relatively conservative throughout the Norian and presumably the Rhaetian. Thus, the fauna from the Placerias Quarry, low down in the Chinle, is pretty similar to the fauna from Ghost Ranch which is much higher in the section. An exception to this appeared to be the dicynodonts, which had never been found in the upper Chinle or Dockum. Because of the Lisowice find, it appears that dicynodonts were present throughout the Late Triassic as well.

The theropod is of interest because of its large size (5m in length and 1.5 meters tall according to Dzik and colleagues) and because the preserved material, including an almost complete skull, suggest tetanuran affinities which would make it the earliest known member of that clade. This distinction was previously held by Zupaysaurus from the Late Triassic of Argentina, which in more recent studies is now believed to be a coelophysoid. A recent study by Nesbitt et al. (2007) has suggested that at least in North America theropod dinosaurs were not only rare components of Late Triassic faunas but only consisted of coelophysoids. Although this has not yet been confirmed by a rigorous study for the rest of Pangaea it appears that this may be true for the rest of the world as well, thus the new Polish find would be of some significance.

To date only a couple of preliminary articles, with some great photos of the material (here and here), have been put forth on what is being called the "Dragon of Lisowice" and hopefully the peer reviewed publications will be out soon.


REFERENCE

Nesbitt, Sterling J., Randall B. Irmis, and William G. Parker. 2007. A critical reevaluation of the Late Triassic dinosaur taxa of North America. Journal of Systematic Palaeontology 5(2):209-243.