Biology Reference
In-Depth Information
Thankfully I had begun planning well in advance and had ample time to adjust and
reframe my research questions. I was looking for information from the deciduous teeth of
living primates that might enhance interpretation of the hominin fossil record. At this point,
I am not aware of any fetal fossil hominins; please contact me if you have information to the
contrary! However, there are quite a few juvenile fossil hominins that have a mixed set of
deciduous and permanent teeth in place. Therefore, the question became whether or not
museum collections had an ample number of chimpanzee specimens fitting this develop-
mental stage. When I discovered that the answer was “yes,” I changed my research ques-
tions. Studying the mixed primary and permanent dentition in living primates would
also likely result in great insight into the mixed dentition present in dozens of fossil
hominins.
As most often presented, the scientific method is a neat, orderly path from observation
through to hypothesis testing, analysis, and presentation of findings. In reality, logistics often
create unforeseen obstacles for completion of the ideal project. In my case, revision of my
research question was necessary due to sample availability. Finding out what materials are
available and what museums will actually let you do with their collections (e.g., in the
case of destructive analyses or transporting specimens off-site for analysis) well in advance
of your presumed start date is essential to getting the project completed on time. Refer to
DiGangi and Moore (Chapter 2), this volume, for more advice on managing logistics.
While I was working on locating collections with specimens appropriate for my study, I
was also considering equipment. I would be taking X-rays of the teeth of museum specimens
to analyze for the project. It was necessary to ensure that all of the images were as clean, reli-
able, and as easy to read as possible. For my Master's project I had worked with traditional X-
rays and knew that it was difficult to ensure that every exposure turned out well. Further-
more, small details like proper alignment of the film, tube, and specimen as well as exposure
time could greatly affect the quality of the resulting image. Another consideration was that
processing traditional X-rays takes a considerable amount of time. Using traditional
methods, review of images would be delayed until after they were developed, leaving less
time to retake images if necessary.
Fortunately, I had two colleagues who were working on their own projects using a portable
X-ray source coupled with a digital film system. This technology makes the process much
faster, with exposed filmbeing scanned and directly uploaded to a computer.With this system,
the film is then erased and reused. Watching the rapidity with which my colleagues imaged
individual specimens intrigued me, so I set to work investigating the available options. Since
their work dealt with full skeletons, they needed larger sensor plates and amuchmore power-
ful X-ray source. My project would be investigating teeth, so I could get the images I needed
using bite-wing film (just like what is used in a dentist's office) and a handheld X-ray source.
After several searches, I ended up locating separate dealers for the X-ray source and the sensor
plates. Even better, I had found digital bite-wing sensor plates that connected via a USB port
directly to my computer. This would considerably speed up image acquisition and review as
images would open immediately on my laptop after exposure.
Since this system is expensive, I decided to rent rather than purchase it. Prior to rental, I
had to arrange for training in the use of the equipment. The dealer of the sensor plates was
kind enough to put me in touch with a veterinary dentist in my area who graciously agreed to
show me how the sensor plates and associated computer software worked together. I took
