New research carried out by the School of Anthropology and Conservation suggest that a biorhythm may be one of the many factors that affect bone growth in children.
Biorhythms are cyclic changes in an organism’s growth or functioning that can be driven by an internal biological clock and synchronised through environmental cues. Evidence of two biorhythms is retained in human tooth enamel in the form of incremental growth lines. The first biorhythm corresponds with a daily, circadian, rhythm: the second corresponds with a longer period rhythm, known as an infradian biorhythm.
Researchers from the Skeletal Biology Research Centre (SBRC) further developed recent studies which indicate that there may be a biorhythm that coordinates aspects of human hard tissue growth and influences adult body size.
The study, led by PhD candidate Rosie Pitfield, investigated if evidence of the infradian biorhythm retained in human teeth corresponds with the microstructural growth of a non-weight bearing bone, in this case the ribs of medieval children, in a sample of fifty human juvenile skeletons.
Using static histomorphometric methods, the incremental growth lines of one permanent tooth from each skeleton was calculated and combined with measures of bone remodelling in a rib from the same individual. Results provide the first evidence that the infradian biorhythm is linked to bone remodelling in children.
The study, funded by the Dora Harvey Memorial Research Scholarship from the University of Kent, also found that children with a faster biorhythm had a larger amount of bone deposited inside the bone structural units and also relatively thicker rib bone overall.
In conclusion, the results support the idea that there is an infradian biorhythm that coordinates aspects of human hard tissue growth.
The study – Microscopic markers of an infradian biorhythm in human juvenile ribs – by Rosie Pitfield, Justyna J. Miskiewicz and Patrick Mahoney is published in the journal Bone.
Image: A cross-section of the rib (100x magnification) of an eight year-old child from medieval Canterbury.