Growth pattern from birth to adulthood in African pygmies of known age

Fernando V Ramirez Rozzi (1) , Yves Koudou (2) , Alain Froment (3) , Yves Le Bouc (4) , Jérémie Botton (5)

1 DEHIPE - Dynamique de l'évolution humaine : individus, populations, espèces [Paris]
2 CESP - Centre de recherche en épidémiologie et santé des populations
3 MNHN - Muséum national d'Histoire naturelle
4 UMRS893 - Centre de Recherche Saint-Antoine
5 CRESS - U1153 - Equipe 6 : ORCHAD - Origines précoces de la santé du développement de l'enfant

The African pygmy phenotype stems from genetic foundations and is considered to be the product of a disturbance in the growth hormone-insulin-like growth factor (GH-IGF) axis. However, when and how the pygmy phenotype is acquired during growth remains unknown. Here we describe growth patterns in Baka pygmies based on two longitudinal studies of individuals of known age, from the time of birth to the age of 25 years. Body size at birth among the Baka is within standard limits, but their growth rate slows significantly during the first two years of life. It then more or less follows the standard pattern, with a growth spurt at adolescence. Their life history variables do not allow the Baka to be distinguished from other populations. Therefore, the pygmy phenotype in the Baka is the result of a change in growth that occurs during infancy, which differentiates them from East African pygmies revealing convergent evolution.

Domains: Biological anthropology

Fernando V Ramirez Rozzi, Yves Koudou, Alain Froment, Yves Le Bouc, Jérémie Botton. Growth pattern from birth to adulthood in African pygmies of known age. Nature Communications, 2015, 6, pp.7672. ⟨10.1038/ncomms8672⟩. ⟨hal-03357388⟩