title: Perikymata distribution in Homo with special reference to the Xujiayao juvenile.
abstract: OBJECTIVE
  This study investigates where the Xujiayao juvenile (I(1) and C(1) ) fits into the array of perikymata distribution patterns found within the genus Homo.
  
  
  METHODS
  In addition to the I(1) and the C(1) of the Xujiayao juvenile, this study includes samples of early Homo (H. rudolfensis and H. erectus), Neandertals, early modern humans (Qafzeh), and recent modern humans from Southern Africa, Newcastle (UK), and North America (Inupiaq, AK). Three sets of analyses were undertaken, including a comparison of percentage of perikymata in the cervical half of the crown, repeated measures analysis of the percentage of total perikymata in each decile, and canonical variates analysis using both total perikymata number and the percentage of perikymata in the cervical half of the crown.
  
  
  RESULTS
  The I(1) and C(1) of early Homo and Neandertals have a lower percentage of perikymata in the cervical half of the crown than modern human samples. Repeated measures analysis reveals clear distinctions in the distribution of perikymata between the modern human and fossil samples. Canonical variates analysis suggests greater differences between modern humans and the fossil samples than within the fossil samples, and classifies the Xujiayao teeth among modern humans.
  
  
  CONCLUSIONS
  The present study further clarifies variation of perikymata distribution patterns within the genus Homo. The perikymata distribution of the Xujiayao juvenile tends to be more similar to that of modern humans than to either early Homo or Neandertals.
authors.affiliation: Key Laboratory of Vertebrate Evolution and Human Origins of Chinese Academy of Sciences, Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, Beijing, 100044, China.
authors.forename: Song
authors.initials: S
authors.lastname: Xing
authors.affiliation: Department of Anthropology, the Ohio State University, Columbus, OH, 43210.
authors.forename: Debbie
authors.initials: D
authors.lastname: Guatelli-Steinberg
authors.affiliation: Department of Anthropology, the Ohio State University, Columbus, OH, 43210.
authors.forename: Mackie
authors.initials: M
authors.lastname: O'Hara
authors.affiliation: Key Laboratory of Vertebrate Evolution and Human Origins of Chinese Academy of Sciences, Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, Beijing, 100044, China.
authors.forename: Xiujie
authors.initials: X
authors.lastname: Wu
authors.affiliation: Key Laboratory of Vertebrate Evolution and Human Origins of Chinese Academy of Sciences, Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, Beijing, 100044, China.
authors.forename: Wu
authors.initials: W
authors.lastname: Liu
authors.affiliation: Department of Anthropology, the George Washington State University, Washington, DC, 20052.
authors.forename: Donald J
authors.initials: DJ
authors.lastname: Reid
mesh_terms: D000818:Animals; D000885:Anthropology, Physical; D002681:China; D003743:Dental Enamel / Q000033:anatomy & histology* / Q000254:growth & development; D015186:Hominidae / Q000502:physiology*; D059125:Neanderthals / Q000033:anatomy & histology; D014070:Tooth / Q000033:anatomy & histology*
keywords: Xujiayao; homo; perikymata; teeth