A cleft palate is a bony defect that is due to the failure of bone union between the two halves of the palate during foetal development. It may be associated with a defect of the upper lip and bone beneath, called the cleft or hare lip (Roberts and Manchester, 2005: 51). The modern incidence of the two conditions is 1 in 700 live births, but of cleft palate alone it is 1 per 1,000 live births (Roberts and Manchester, 2005: 51). Prevalence rates reported for live births for cleft lip with or without cleft palate and cleft palate alone varies within different racial groups.The highest prevalence rates for are reported for Native Americans and Asians. Africans have the lowest prevalence rates (Wikipedia).
The two problems of cleft palate/lip and cleft palate alone are in fact somewhat distinct entities with different causative factors (Roberts and Manchester, 2005: 51). Cases of cleft palate are multifactorial in cause but have a strong family history and are therefore predominantly genetic in origin (Roberts and Manchester, 2005: 51). It is presumed that the problem was probably as common in the past as it is today (and is seen more in females). However, cleft lip frequency does not vary as much as cleft palate among populations and may possibly be more related to environmental influences (Roberts and Manchester, 2005: 51).
Most babies with a cleft lip can be breastfed. However, some babies have difficulty creating a seal around the nipple and may not be able to breastfeed. Cleft palate can also cause problems with speech, tooth development and hearing (because the tube that connects the ear to the palate (the Eustachian tube) can be affected) (BUPA factsheet). Neonates with cleft palate, therefore require potentially time-consuming and laborious care. This may be provided in western societies today, but may have been unacceptable or even impossible in earlier societies, for example, in hunter-gatherer populations (Roberts and Manchester, 2005: 52). Neonatal death of babies with this condition may, therefore, have been common in the distant past. Such deaths may have been motivated by socio-economic attitudes. The respiratory and speech problems that can be associated with cleft palate, in addition to not being able to feed properly and the potential outward disfigurement (for those with cleft lip also) could have attached stigma to, and the ostracism of, people affected, especially in past communities where the condition was little understood (Roberts and Manchester, 2005: 52).
The preservation of fragile neonatal skulls is rarely good enough to allow a diagnosis of cleft palate to be made. Even diagnosing the condition in adult skeletons is fraught with difficulty because of the fragility of the palate bones, and the problem of distinguishing post-mortem breakage from ante-mortem cleft palate (Roberts and Manchester, 2005: 52). There are, however, reported examples from archaeological contexts: a child from 6th-7th century AD Britain, crania exhibiting both cleft palate and hare lip from 2,000-4,000 BP California, and an 11th-12th century AD British male aged 40-50 years old (Roberts and Manchester, 2005: 52).
BUPA Factsheet: http://hcd2.bupa.co.uk/fact_sheets/Mosby_factsheets/cleft_lip.html (accessed April 1, 2008).
Roberts, C and Manchester, K. 2005. The Archaeology of Disease. Third Edition. Stroud: Sutton Publishing
Wikipedia contributors, “Clefting prevalence in different cultures,” Wikipedia, The Free Encyclopedia, http://en.wikipedia.org/w/index.php?title=Clefting_prevalence_in_different_cultures&oldid=201055636 (accessed April 1, 2008).