Putative native South Amerindian origin of head lice clade F: evidence from head lice nits infesting human shrunken heads

Abstract

The head louse, Pediculus humanus capitis, is a strictly obligate human ectoparasite with a long history of association with humans. Here, 17 ancient head lice nits were recovered from six shrunken human heads (known as tsantsas) of individuals from the Shuar/Jivaro tribe, a native Amazonian population from Ecuador, South America. Cytochrome b DNA analysis revealed the presence of three known mitochondrial clades. Clade A was the most frequent (52.94%), followed by F (35.29%), and B (11.76%). Eleven haplotypes were found in 17 samples, and nine of the haplotypes were novel, indicating an unusually high genetic diversity. In conclusion, we confirmed the presence of clades A, B and F in South Amerindian population. Moreover, the description of clade F, together with its previous reports in another Amerindian population from French Guiana, strongly support the hypothesis of a native South American origin for this clade, and probably derived from clade B which was carried to America by an ancestral Eurasian Beringian population. Further support to our conclusion and new insights might come from the analysis of a larger collection of modern and ancient native American lice.

Human pediculosis, a global public health problem

“…Clade F also included a few sequences of lice from Argentina and Mexico [ 25 ]. The recovery of ancient head louse nits from six shrunken human heads further supports the hypothesis of a native South American origin of clade F [ 29 ]. P. mjobergi , a louse of South American monkeys of the Cebidae family, also belongs to this clade.…”

Are museums the future of evolutionary medicine?

“…This perspective could respond to certain ethical reflections, and in particular those concerning the scientific over-solicitation of the populations studied and the impacts generated on their life and functioning-impacts that have already tainted the relationship between scientists and populations. Faced with the distrust of certain Indigenous peoples regarding the fear of the theft of their genetic (and globally biocultural) heritage, is it possible to draw legally and respectfully from these objects constituting the collections of museums of ethnology, ethnography, anthropology and natural history?We have recently been able to show the interest of a bio-molecular study of the typing of lice subspecies on a set of six reduced heads (tsantsas) from the Achuar/Jivaro (Bolivia/ Ecuador): beyond the precise identification of ectoparasites, it also highlights that historical migratory movements can be reconstructed (in particular clades that were carried to America by an ancestral Eurasian Beringian population thousands of years ago) (Amanzougaghene et al, 2022).Other scientific work is possible, which would provide information as much about the physical reality of the object as about its journey and/or the history of the population from which it came. Currently, at the quai Branly-Jacques Chirac museum (Paris, France), we are developing the bio-molecular analysis of partially carbonized residues in a dozen African pipe mouthpieces and chambers (sub-Saharan Africa, Central Africa, and East Africa): if the proteins of botanical species could be highlighted (paleo-proteomics), allowing the identification of the type of plant smoked (tobacco, cannabis, other local species), human DNA related to the saliva of the smoker(s) will most certainly also be…”

“…We have recently been able to show the interest of a bio-molecular study of the typing of lice subspecies on a set of six reduced heads (tsantsas) from the Achuar/Jivaro (Bolivia/ Ecuador): beyond the precise identification of ectoparasites, it also highlights that historical migratory movements can be reconstructed (in particular clades that were carried to America by an ancestral Eurasian Beringian population thousands of years ago) (Amanzougaghene et al, 2022).…”