If you have noticed, you will realize that people from the Island nation of Madagascar look very much different in complexion and other comparisons to other Africans.
Why do the Malagasy people of Africa do not look at Africans?
According to a study published in May 2005 by a UK team, half of the genetic lineages of human inhabitants of Madagascar come from Borneo, 4500 miles away, and the other half comes from East Africa.
Madagascar, the largest island in the Indian Ocean, is 250 miles (400 kilometres) from Africa and 4000 miles (6400 kilometres) from Indonesia. Because of its isolation, the majority of its mammals, half of its birds, and the majority of its plants are found nowhere else on the planet.
The new findings, which were published in the American Journal of Human Genetics, show that the people of Madagascar are also unique, with half of their genetic lineages deriving from settlers from Borneo and the other half from East Africa.
This settlement could have been as recent as 1500 years ago, around the time the Saxons invaded Britain, according to archaeological evidence.
“The origins of the language spoken in Madagascar, Malagasy, suggested Indonesian connections because its closest relative is the Maanyan language, spoken in southern Borneo,” said Dr Matthew Hurles, of the Wellcome Trust Sanger Institute. “For the first time, we have been able to assign every genetic lineage in the Malagasy population to a likely geographic origin with a high degree of confidence.”
“Malagasy peoples are a roughly 50:50 mix of two ancestral groups: Indonesians and East Africans. It is important to realise that these lineages have intermingled over intervening centuries since settlement, so modern Malagasy have ancestry in both Indonesia and Africa.”
The researchers from Cambridge, Oxford, and Leicester studied DNA diversity using two types of DNA markers: Y chromosomes, which are inherited only by males, and mitochondrial DNA, which is inherited only by females. They compared the Malagasy to populations from all over the Indian Ocean.
The Malagasy’s non-African Y chromosomes were much more similar to the non-African Y chromosomes found in Borneo than any other population, demonstrating striking agreement between genetic and linguistic evidence. Similarly, for each mitochondrial DNA sample, a ‘Centre of Gravity was calculated to suggest a possible geographical origin.
This entails calculating a geographical average of the best matches’ locations from a large database of mitochondrial lineages from all over the world.
“The Centres of Gravity fell in the islands of southeast Asia or in sub-Saharan Africa,” explained Dr Peter Forster, from the McDonald Institute for Archaeological Research, University of Cambridge, one of the co-authors.
“The evidence from these two independent bits of DNA supports the linguistic evidence in suggesting that a migrating population made their way 4500 miles across the Indian Ocean from Borneo.”
Even though the Africa coast is only one-twentieth of the distance to Indonesia, it appears that migrations from Africa may have been more limited, as less of the diversity seen in the source population has survived in Madagascar.
But why, if the population is a 50:50 mix, is the language almost exclusively derived from Indonesia?
“It is a very interesting question, for which we have as yet no certain answer, as to how the African contribution to Malagasy culture, evident in biology and in aspects of economic and material culture, was so largely erased in the realm of language,” commented Professor Robert Dewar, of The McDonald Institute for Archaeological Research, University of Cambridge.
“This research highlights the differing, and complementary, contributions of biology and linguistics to the understanding of prehistory.”
The population structure in Madagascar is a fascinating snapshot of human history and a testament to the remarkable abilities of early populations to undertake migrations across vast reaches of the ocean. It may also be important today for cutting edge medical science.
“There has recently been dramatic progress in the development of experimental and statistical methods appropriate for gene mapping in admixed populations,” said David Goldstein, Wolfson Professor of Genetics, University College London.
“To succeed, however, these methods depend on populations with well defined historical admixtures. This work shows provides compelling evidence that the Malagasy are such a population, and again shows the value of the careful study of human population structure.”
Our human history is a rich mix of peoples and their movement, of success and failure. Madagascar holds an enriching tale of the ability of humans to survive and to reach new lands.