A hypothesis: Autonomic rhythms are reflected in growth lines of teeth in humans and extinct archosaurs

O. Appenzeller, H. C. Gunga, C. Qualls, R. Furlan, A. Porta, S. G. Lucas, A. B. Heckert, K. Kirsch, M. A. Costa-Junqueira, S. E. Guillén, M. Sander, T. Schneider, B. Blottner

Research output: Contribution to journalArticlepeer-review


A major determinant of tooth architecture is the arrangement of lines in dentin and in the enamel following the contour of the surface. Since the original description of these lines in the 19th century, they have been attributed to recurring events during tooth development. They have also attracted the attention of dental scientists and anthropologists; however, to date, studies of these structures have been largely theoretical and microscopic. We show here that the statistical properties of the spacing between the lines are similar in teeth from both ancient and modern humans and from extinct archosaurs, reptiles that lived tens or hundreds of millions of years ago-they also resemble heart rate variability of living humans. We propose that the deposition of these recurring structures is controlled by the autonomic nervous system. This control accounts for their regularity and recurrent nature and implies that the lines are an expression of a biologic rhythm which has been conserved throughout evolution. Details of the rhythms give clues to life styles in ancient civilizations and to the physiology of extinct archosaurs.

Original languageEnglish
Pages (from-to)115-119
Number of pages5
JournalAutonomic Neuroscience: Basic and Clinical
Issue number2
Publication statusPublished - Feb 7 2005


  • Autonomic nervous system
  • Biologic rhythms
  • Evolution
  • Extinct archosaurs
  • Human
  • Parametric and nonparametric autoregressive spectral analysis
  • Teeth

ASJC Scopus subject areas

  • Clinical Neurology
  • Cellular and Molecular Neuroscience
  • Endocrine and Autonomic Systems


Dive into the research topics of 'A hypothesis: Autonomic rhythms are reflected in growth lines of teeth in humans and extinct archosaurs'. Together they form a unique fingerprint.

Cite this