eprintid: 10115102 rev_number: 17 eprint_status: archive userid: 608 dir: disk0/10/11/51/02 datestamp: 2020-11-16 14:13:10 lastmod: 2020-11-16 14:13:10 status_changed: 2020-11-16 14:13:10 type: article metadata_visibility: show creators_name: Dean, C creators_name: Zanolli, C creators_name: Le Cabec, A creators_name: Tawane, M creators_name: Garrevoet, J creators_name: Mazurier, A creators_name: Macchiarelli, R title: Growth and development of the third permanent molar in Paranthropus robustus from Swartkrans, South Africa ispublished: pub divisions: UCL divisions: A01 divisions: B02 divisions: C08 divisions: D09 keywords: Anatomy, Biophysics, Evolution note: This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/. abstract: Third permanent molars (M3s) are the last tooth to form but have not been used to estimate age at dental maturation in early fossil hominins because direct histological evidence for the timing of their growth has been lacking. We investigated an isolated maxillary M3 (SK 835) from the 1.5 to 1.8-million-year-old (Mya) site of Swartkrans, South Africa, attributed to Paranthropus robustus. Tissue proportions of this specimen were assessed using 3D X-ray micro-tomography. Thin ground sections were used to image daily growth increments in enamel and dentine. Transmitted light microscopy and synchrotron X-ray fluorescence imaging revealed fluctuations in Ca concentration that coincide with daily growth increments. We used regional daily secretion rates and Sr marker-lines to reconstruct tooth growth along the enamel/dentine and then cementum/dentine boundaries. Cumulative growth curves for increasing enamel thickness and tooth height and age-of-attainment estimates for fractional stages of tooth formation differed from those in modern humans. These now provide additional means for assessing late maturation in early hominins. M3 formation took ≥ 7 years in SK 835 and completion of the roots would have occurred between 11 and 14 years of age. Estimated age at dental maturation in this fossil hominin compares well with what is known for living great apes. date: 2020-11-04 date_type: published official_url: https://doi.org/10.1038/s41598-020-76032-2 oa_status: green full_text_type: pub pmcid: PMC7642444 language: eng primo: open primo_central: open_green verified: verified_manual elements_id: 1828751 doi: 10.1038/s41598-020-76032-2 pii: 10.1038/s41598-020-76032-2 lyricists_name: Dean, Michael lyricists_id: MCDEA52 actors_name: Allington-Smith, Dominic actors_id: DAALL44 actors_role: owner full_text_status: public publication: Scientific Reports volume: 10 article_number: 19053 event_location: England citation: Dean, C; Zanolli, C; Le Cabec, A; Tawane, M; Garrevoet, J; Mazurier, A; Macchiarelli, R; (2020) Growth and development of the third permanent molar in Paranthropus robustus from Swartkrans, South Africa. Scientific Reports , 10 , Article 19053. 10.1038/s41598-020-76032-2 <https://doi.org/10.1038/s41598-020-76032-2>. Green open access document_url: https://discovery.ucl.ac.uk/id/eprint/10115102/1/Growth%20and%20development%20of%20the%20third%20permanent%20molar%20in%20Paranthropus%20robustus%20from%20Swartkrans%2C%20South%20Africa.pdf document_url: https://discovery.ucl.ac.uk/id/eprint/10115102/8/Dean_et_al_2020_SI.pdf