HOMO - Journal of Comparative Human Biology 64 (2013) 205–214 Contents lists available at SciVerse ScienceDirect HOMO - Journal of Comparative Human Biology journal homepage: www.elsevier.com/locate/jchb Is increased constitutive skin and hair pigmentation an early sign of puberty? A. Sitek a,∗ , E. ˙ Z˛ adzi ´ nska a , I. Rosset a , B. Antoszewski b a Department of Anthropology, Faculty of Biology and Environmental Protection, University of Łód´z, 90-237 Łód´z, Poland b Department of Plastic, Reconstructive and Aesthetic Surgery, Institute of Surgery, Medical University of Łód´z, 90-153 Łód´z, Poland article info Article history: Received 29 August 2012 Accepted 13 March 2013 Available online 17 April 2013 abstract The paper analyzes data concerning the constitutive skin and hair pigmentation of 7–10-year-old Polish children to examine whether the hormonal activity of the gonads, which increases in this period, causes changes in pigmentation levels that may be considered an early sign of puberty. The study involved 289 children (151 girls and 138 boys). Skin pigmentation was examined on the medial side of the arm, while hair pigmentation on strands of hair close to the scalp in the occipital area. Additionally, body height (B-v) was measured and compared with population norms. On this basis, it was ascer- tained that the studied sample was representative of the population from which it was taken and that it represented the prepubertal and early pubertal stages of ontogeny (prior to the pubertal growth spurt or the first menstruation in the studied girls). It was found that in 7–10-year-old Polish children there is a statistically significant (p = 0.001) increase in skin and hair pigmentation levels, while the degree of pigmentation of both structures at this stage of ontogeny is sexually dimorphic: girls are characterized by stronger pigmen- tation than boys. At the age of 10 years, the dimorphic differences in skin pigmentation intensify due to a rapid rise in pigmentation in girls. This change may be deemed an early morphological sign of puberty, as it precedes the pubertal growth spurt and menar- che. This fast increase in skin pigmentation is not paralleled by an analogous change in hair pigmentation. © 2013 Published by Elsevier GmbH. ∗ Corresponding author. Tel.: +48 42 6354454; fax: +48 42 6354413. E-mail address: asitek@biol.uni.lodz.pl (A. Sitek). 0018-442X/$ – see front matter © 2013 Published by Elsevier GmbH. http://dx.doi.org/10.1016/j.jchb.2013.03.003