rASUDAS is a new web-application using a statistical framework that estimates the ancestry of unknown individuals based on their suite of tooth crown and root traits. Users can choose between 21 independent traits, scored following the well-known Arizona State University Dental Anthropology System (ASUDAS). It is powered by a world-wide reference sample representing approximately 30000 individuals from seven biogeographic regions. The statistical framework and the web application were developed using the R open source programming language. The framework uses a naive Bayes classifier to assign posterior probabilities for individual group assignment. To test the application, 150 individuals were selected from the C. G. Turner II database. In a seven-group analysis, the model correctly assigned individuals to groups 51.8% of the time (chance is 14%!). In a four-group analysis (chance = 25%), classification accuracy improved to 66.7%. With three groups, accuracy was at 72.7%. It is still necessary to validate the program using forensic cases and to augment the reference sample with modern skeletal data. However, results from the current version of rASUDAS are presented as proof of concept on the potential of dental morphology in ancestry estimation in medico-legal contexts. This software has been described in the first issue of the new scientific journal Forensic Anthropology. The application is available at rASUDAS is free! You can try it osteomics.

Forensic Anthropology Journal
New scientific journal: Forensic Anthropology

Why teeth?

The incorporation of dental morphological analyses into forensic anthropological casework has several advantages:

  1. there is a robust body of literature outlining the heritability, development, evolution, and population history of dental morphology, which allows for accurate interpretations of results;
  2. teeth are not subject to plastic change over a lifetime; and
  3. teeth are often better preserved than other parts of the skeleton; Further,
  4. dental morphology represents a different aspect of the genotype and is the result of distinct evolutionary relationships that go beyond the mid-face and shape and size of the cranial vault.

The ability to incorporate more information from the skeleton when assessing ancestry is critical in creating accurate estimates of ancestry. Dental morphology couched in a statistical framework can become an integral part of the methods regularly used by forensic anthropologists in ancestry estimation.

rASUDAS is free! You can try it here.

Feel free to read the paper, here is a very cool historical snippet from it on how me and Navega were working on these kind of projects early on in 2015.

rASUDAS creation
Osteomics becoming part of forensic anthropology history!

Congrats to my colleagues,

rASUDAS: A New Web-Based Application for Estimating Ancestry from Tooth Morphology

G. Richard Scott, Marin A. Pilloud, David Navega, João d’Oliveira Coelho, Eugénia Cunha, Joel D. Irish

DOI: http://dx.doi.org/10.5744/fa.2018.0003

Bo asudas rsrsrs

We have a new scientific article out. It discusses how bone mineral density correlates with age, and thus can be used to model age at death from human remains. We employed artificial neural networks, a simple machine learning technique, to learn patterns of femur densitometric data gathered in 100 female individuals from the Coimbra Identified Skeletal Collection. The mean error of the method, depending on the variables used, ranged from 9.19 to 13.49 years. It is also the first publication about the DXAGE app that was developed with the cooperation with some team members from the Laboratory of Forensic Anthropology, UC. Despite preliminary, and only indicated for skeletal remains of adult females, it shows a very original approach for bioarchaeologists and forensic anthropologists to assess age at death.

figure 2
The neural network architecture used.

Congrats to my peers.

DXAGE: A New Method for Age at Death Estimation Based on Femoral Bone Mineral Density and Artificial Neural Networks

D. Navega, J. d’Oliveira Coelho, E. Cunha, F. Curate

DOI: http://dx.doi.org/10.1111/1556-4029.13582

Best regards, Jow-nhs


I am very pleased to announce that the HOT team has a new site:

hot bones
Click on the image to visit HOT BONES

The coolest thing I learned when developing HOT BONES was to create this beauties, using only the R programming language and a simple sheet from Excel.

Dead Weight paper is out

Besides, we published recently, with some of the team members a new paper, Dead Weight: validation of mass regression equations on experimentally burned skeletal remains to assess skeleton completeness, on Science and Justice. It tests the MassReg app on the experimentally burned skeletons of the CEIXXI available at Laboratory of Forensic Anthropology, UC. Despite MassReg being initially developed for non-burned skeletal remains, it seems to perform as well on burned skeletal remains as other techniques (e.g. comparing to references). Thus it is a new promising and useful tool to assess skeletal completeness.

Congrats to all involved!

Dead weight: Validation of mass regression equations on experimentally burned skeletal remains to assess skeleton completeness

D. Gonçalves, J. d’Oliveira Coelho, A. Amarante, C. Makhoul, I. Oliveira-Santos, D. Navega, E. Cunha

DOI: http://dx.doi.org/10.1016/j.scijus.2017.07.003

Best regards, Johny

Hi everyone,

So this is one of those really cool things that passed through my mind when I was a kid. Luckily, it is a dream I can remove from the checklist! So I appeared on a documentary on biological anthropology, more specifically about a recently discovered archaeological skeletal collection from Lagos, Portugal. This collection is unique, worldwide, in how much it can tell us about slavery related to the Age of Discovery.

Die Sklaven von Lagos

die sklaven
Click on the image to watch the documentaries episodes.

The documentary is split into 6 episodes:

  • The skeletons from Algarve
  • Bioarchaeology: working with the bones
  • History meets CSI
  • What the teeth tell us
  • A piece of history for the nameless
  • The general interview with Maria Teresa Ferreira

All very interesting and available in german and english, my 15 seconds of fame are mostly on the fifth one, but best is to watch all of them!

Yours, j d’o c

Congrats to me!

I have finally finished a full tree of knowledge in Duolingo. This means there are not any new games for me to try, with this language in specific, in the platform. Yet, Danish sure is a difficult language, while I can somewhat read it now, it’s still really hard to understand by listening. I’ve watched a few series and listened to a few audiobooks to improve that, yet…

danish is conqueres
Duolingo team celebrates with you.

Well, just wanted to share this little achievement. By the way, you can add me as your friend and check my general scores in all languages:

delvispresley @ duoling

No doubts, one of my favorite sites on the web. Knowledge offered for free is the greatest thing ever!

“Hvis man fortier et spøgelse, vokser det sig større” - grønlandsk ordsprog