Why not marry your cousin? Millions do

In 2012, The Conversation had an article about cousin marriage:

The topic of consanguineous marriage raises both interest and unease in Western societies. For those who are wondering, that big word means “marrying your cousin”.

But why would anyone want to marry a cousin when there are so many other potential partners out there?

In generational terms this mode of thought is actually quite recent, and until the middle of the 19th century first cousin marriage was common in most Western countries, in part due to the shortage of available unrelated spouses in many outlying areas.

Further, many of the ill-effects on health that have been ascribed to “inbreeding” are more probably due to a wide range of adverse non-genetic factors, including young maternal age, very short birth intervals, trans-placental infection of the developing fetus with organisms such as rubella and cytomegalovirus, and inadequate nutrition both during pregnancy and early childhood.

In assessing whether or not consanguinity is “good” or “bad” there has been a notable failure to take into account the social and economic benefits of close kin marriage, which is a particularly important consideration in the poorer sections of societies where consanguinity is more common. Or to acknowledge that wives in consanguineous unions generally seem to enjoy more equal status.

Alan Bittles is the author of "Consanguinity in Context".