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• Levi Raskin

Levi Raskin

Advisor: Maja Å eÅ¡elj

Is Dental Development an Honest Signal of Phylogenetic Placement?

The scarcity of data usable for interpreting the human evolutionary past has forced paleoanthropologists to utilize characteristics in phylogenetic analysis without the requisite study required to understand whether those traits are in fact phylogenetically informative. Dental development, like many characteristics related to life history, is highly variable between taxa and while there may be clear trends at higher taxonomic rankings, the variability of life history traits beguile classification at lower taxonomic levels, like tribe. Despite that, because of the abundance of teeth in the fossil record, dental traits have been utilized to resolve hominin phylogenies almost since its methodological inception. In particular, easy-to-access characteristics like perikymata, a roughly weekly growth line visible on the tooth’s surface, have been used recently to try and resolve speciation in situations where either hominin phylogenetics are poorly understood or there is a paucity of skeletal evidence.

By continuing the reaction against dental development in phylogenetics begun by Kufeldt and Wood (2022), we will expand on their conclusions and disseminate to the paleoanthropological community how, where, and in what ways perikymata can, or cannot, be used in phylogenetics. This summer, we are imaging casts of great gpe teeth to collect data on perikymata counts to eventually test their ability to resolve evolutionary relationships in the great ape clade. If perikymata cannot reproduce the known phylogeny within the great apes, then we will have to doubt its power for reconstructing evolutionary relationships within hominins. If perikymata are able to clearly recreate the genetic tree, then perikymata may be a true proxy of evolutionary relatedness. While more studies at lower taxonomic levels should be conducted, its usage in paleoanthropology would tentatively be supported.