Photo by: Purwo Kuncoro

Grantee Spotlight: Alexandra Uhl

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“These are some of the non-adult crania we scanned at Universität Tübingen. That’s our CT scanner in the background. We also did DNA analysis on the teeth from these individuals.”

In the spring of 2014 The Leakey Foundation awarded Alexandra Uhl, PhD candidate from the University of Tübingen in Germany, a research grant for her project entitled “Sex determination in geographically and ontogenetically diverse samples.”

My research looks at sexual dimorphism (differences between males and females) in the bony labyrinth, which is the rigid outer wall of the inner ear, across different modern human populations and different age groups. When human skeletal remains are found in an archaeological context, it can be difficult to estimate the sex of the individual if the bones and features that are sexually dimorphic, such as the pelvis and skull, are incomplete or broken. However, the bony labyrinth is housed in the petrous part of the temporal bone called the petrous pyramid, the best preserved area of the human skeleton and the most often found at archaeological sites and crime scenes. The petrous portion can even survive cremations. Since previous research on adult Europeans has found sexual dimorphism in the bony labyrinth, my research will explore this in world wide populations and different age groups.

Getting one individual ready for a batch scan at Witwatersrand.

Non-adults are extremely difficult to estimate sex for because they have not yet gone through puberty, which would make their bones more female or male. Thus, a technique that can be used on juveniles for sex estimation is extremely exciting, and since the bony labyrinth is fully formed in utero (before birth), sexual dimorphism should be present no matter what age an individual is. We plan to also apply the technique to Neanderthal and Upper Paleolithic specimens, for which sex estimation is also difficult due to robust features.

In September 2014 I went to the University of Witwatersrand in Johannesburg, South Africa to collect 58 scans of Zulu skulls from the Dart collection. I also measured the pelvis and post crania. In November 2014 I will go to Pennsylvania State University to make 40 scans of Oneota (pre-contact Native American) skulls and also measure the pelvis and postcrania. I also plan to do sex estimation using DNA analysis. I am working with a German skeletal collection At the University of Tuebingen, Germany as well.

Alexandra Uhl at the Cradle of Humankind

A Zulu skull from the Dart Collection at Witwatersrand. Female, age 20.

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Alexandra Uhl touring the Cradle of Humankind with Francis Thackeray

Batch scan at Witwatersrand. “This is how we saved time scanning. You carefully stack 2-3 individuals in the tube and set the scanner to do a batch scan. This way you don’t have to come back every 20 minutes to switch skulls, instead just every 40-60 minutes.”



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