A new paper in the Journal of Human Evolution by Matthew Skinner and colleagues  announces the new availability of an open archive of microCT data from the site of Kromdraai, South Africa, with a large collection of hominin specimens curated in Pretoria at the Ditsong National Museum:
Digital representations of vertebrate fossils are quickly becoming a standard source of data for scientific inquiry and non-destructive imaging of the internal structure of fossils is opening up new avenues of research that will further our understanding of fossil taxa. The purpose of this paper is to formally announce the availability of high-resolution microtomographic (microCT) scans of hominin fossils from the site of Kromdraai B (known as the ‘hominin site’, as opposed to Kromdraai A, the ‘faunal site’), South Africa. These microCT scans are the result of a collaborative research project between the curatorial institution of the Kromdraai fossils, the Ditsong National Museum of Natural History (DNMNH; formerly the Transvaal Museum) in Pretoria, South Africa and the Department of Human Evolution of the Max Planck Institute for Evolutionary Anthropology (MPI-EVA) in Leipzig, Germany.
In publishing these scans, we hope to stimulate research on these important specimens using virtual representations of the original fossils. We also envision that increased access to such data will stimulate additional research requiring study of the original fossils.
This is really an outstanding development, a rich resource for education and further research. I want to congratulate all the people involved!
The CT archive is hosted at the Max Planck Institute website, "DITSONG - CT Archive".
Solving the problem of access has been especially difficult for scan data of hominin fossils. The physical specimens that represent ancient hominins are curated by museums in many countries around the world. Museums and other national institutions have a mission to steward their historical and cultural resources. A central archive, whether from a government sponsor like NSF or from a commercial entity such as Google, would be more convenient for researchers and save facilities and labor costs, but might take away some of the stewardship capability exerted by the separate institutions now. So to see a large institute entering into this kind of collaboration with a prominent national museum in another country makes me hopeful that the field is being persuaded about the benefits of more open access -- especially for educational use.
Paleoanthropology is a comparative science, and good science requires comparing a specimen to the variation across samples of fossils and living primates. This is why casts have had such an important role in the history of the field. The key fossil specimens may never be in the same room with each other, but casts can be brought together for comparisons.
Now with CT data, technology in principle makes it possible for every paleoanthropologist to have an archive of fossil morphology. That has such a potential to save morphologists time and trouble. Simply keying a publicly available 3-d scan model with a label can allow much clearer communication about the form of a trait that may appear ambiguous on a fossil fragment.
So why has this technology taken so long to get into the hands of paleoanthropologists? In 2005, I reflected on an article that forecasted a bright future for CT data archives in paleoanthropology: "Frontiers of human origins". I wrote:
Personally, I think CT will have a limited set of impacts. The best thing is that it will allow any lab in the world to have as full a set of comparative data as have been released. Currently, it's useless for that purpose; there's just not enough access. But that is changing, and CT scans are as useful to a practiced eye as casts -- which are much less available today even as CT increases. In fact, high-resolution CT may essentially end casting of new fossils, since that is one of the major sources of damage. We'll be doing a lot of comparative work with imaging in the future.
There is still not enough access. There are a very limited number of scans of hominin fossils that are openly available for download -- for example, Harvard's Peabody Museum made CT data for the Skhul V cranium available several years ago. Other CT data are available for sale; some are available with a consortium membership, and some can be acquired by direct inquiry to researchers. Right now, a student cannot use these Kromdraai data in comparison with other open fossil data unless that student is well-connected in the hierarchy of paleoanthropology. The day is still far away when every laboratory has access to a useful archive of fossil hominin morphology.