Introducing the Dental Microwear Image Library

Dental microwear, seen in the tiny pits and scratches on a tooth, provides lots of detailed data for inferring diet and chewing behavior in animals. Analyses are often conducted by digitizing highly magnified images of the tooth surface and counting up and classifying the various microscopic features. Animals with a certain percentage of pits and scratches may have browsing habits, whereas those with another profile may be grazers. By measuring extant animals with known diet, we can (hopefully) infer the diet of extinct animals.

Dental microwear; modified from figure 3 in Mihlbachler et al., 2012

In this age of increasingly open science, microwear studies can be problematic. A cornerstone of science is reproducibility - yet, inter-observer variation and error can greatly affect measured data. Furthermore, one study alone may generate dozens or hundreds of images. Even if you wanted to re-analyze teeth, it's pretty tough - how could you get access to the necessary images? Ideally, we want a world where anyone can access the raw image data, make their own observations, double-check published analyses, and add new data for comparison.

Thus, a new project - called the Dental Microwear Image Library, or DMIL - may change things. Assembled by Brian Lee Beatty and Matthew Mihlbachler, the website aims to become a clearinghouse for dental microwear images. This will allow greater standardization of analyses and hopefully better interpretations of paleoecology and diet for extinct organisms and modern organisms. The first data (from a recent paper in Paleontologia Electronica) are now posted, along with many other data sets.

Brian Lee Beatty (who blogs at The Aquatic Amniote and tweets as @Vanderhoofius) was kind enough to answer a few questions about the DMIL. Thanks, Brian!

Was there a particular moment or incident that inspired you to build the DMIL? If so, what was it?
As we set out to test and develop the method that Nikos Solounias and Gina Semprebon started, we found ourselves frustrated by not only the lack of information on methods that were given in most microwear papers, but also the inability for people to check their work. Interobserver error is a major cause of problems for microwear, and the only way for anyone to be aware of those differences is if they compare interpretations of microwear surfaces, not just their numbers on a spreadsheet. The DMIL was the only possible solution to the need to share such images.

How has community response been so far? Is there any particular type of skepticism that you're working to overcome?
The DMIL hasn't yet come up against skepticism, but our first paper on this method that uses it has.

What license, if any, are the data housed under? Or is it on a case-by-case basis?
There is no license for the data. We want it to be completely open-access and simply available.

How would you envision the DMIL 10 years from now? What goals might you have for the long-term?
We hope it will be a place that people can use to learn how to use the methods we are continuing to develop. I most sincerely hope that it will not only be home to our own data, but also be a place for others to deposit their data using similar methods so that more work of this sort is available in a similar, comparable format.

Authors of the recent paper in PE, along with a research assistant. Photos courtesy of Brian Lee Beatty.

For more information, check out the DMIL, or read the recent paper (open access) about the work.

Citation:
Mihlbachler, Matthew C., Beatty, Brian L., Caldera-Siu, Angela, Chan, Doris, and Lee, Richard, 2012. Error rates and observer bias in dental microwear analysis using light microscopy. Palaeontologia Electronica Vol. 15, Issue 1;12A,22p.

The Open Museum Notebook - Torosaurus Style

A new paper on the Torosaurus / Triceratops issue was just published in PLoS ONE, bringing some additional analysis to the table. I won't comment on it any more here (I'm saving my thoughts for a formal reply on the PLoS ONE website itself), other than to refer you to my own paper and the Scannella & Horner response.

In any case, I have a pile of notes from my own work on Torosaurus (or whatever we should call it), and figured it was time I distribute them a little more widely. So, I just uploaded my notes on the Yale Torosaurus specimens to figshare.com. There isn't really anything earthshaking in there (most of the meat of it has been previously published), but in any case now other folks can use them. The sketches of real bone vs. reconstruction should be particularly useful.

My sincere hope is that at least a few other paleontologists will follow suit with their own notebooks - there are a lot of unused data that will never see the light of day otherwise. I also have a goal of gradually digitizing and posting my other museum notebooks, but that will probably take some time!

Citation and Link

Notes and Observations on Specimens of Torosaurus at the Yale Peabody Museum of Natural History. Andrew Farke. Figshare. Retrieved 15:40, March 02, 2012 hdl.handle.net/10779/664bf2cb5ac486da32c7fb7261e595cd

Update: Since this posted, I have uploaded a number of other notebooks. Find them on my figshare author page.

Building Momentum for Open Data in Paleontology

Thanks to a variety of "real world" concerns and deadlines, I've been a little sparse on the blog for the past few weeks. But, that doesn't mean that important things haven't been happening elsewhere in the realm of digital paleontology. If you haven't already, take a look at and consider adding your signature to "An Open Letter in Support of Palaeontological Digital Data Archiving." Kudos to the folks who got the ball rolling on this effort! As paleontology becomes more data driven, and as more of those data are digitized, we need to get our act together as a community now.