Thursday, August 13, 2009

Dog Domestication Likely Began in Africa

Jennifer Viegas, Discovery News

Aug. 3, 2009 -- Modern humans originated in Africa, and now it looks like man's best friend first emerged there too.

An extensive genetic study on the ancestry of African village dogs points to a Eurasian -- possibly North African -- origin for the domestication of dogs.

Prior research concluded that dogs likely originated in East Asia. However, this latest study, the most thorough investigation ever on the ancestry of African village dogs, indicates otherwise.

"Village" dogs are local, semi-feral dogs that cluster around human settlements in much of the world.

"I think our results cast some doubt on the hypothesis of an East Asian origin for dog domestication that was put forward based on previous mitochondrial DNA genetic research," lead author Adam Boyko told Discovery News.

Boyko, a research associate in the Department of Biological Statistics and Computational Biology at Cornell University, and his colleagues looked at three genetic markers for 318 village dogs from seven regions in Egypt, Uganda and Namibia. The scientists performed the same DNA analysis on a number of putatively African dog breeds, as well as on Puerto Rican street dogs and mixed breed dogs from the United States.

The scientists determined genetic diversity was just as high for the African dogs as it was for the East Asian village dogs that were the focus of the earlier research.

"Species tend to show the highest genetic diversity near their place of origin," said Boyko. He explained that this is because the species have "been there longer and therefore have had more time to accumulate diversity, and because as a species expands its range by colonizing a new region, it usually does so with a relatively small band of individuals carrying just a subset of the genetic diversity found in the ancestral population."

Humans might have then first domesticated dogs from wolves in Africa, with Egypt being one possibility, since wolves are native to that region. Many existing wild species of canid, such as the Egyptian jackal, popularly featured in ancient Egyptian art, are now critically endangered.

The new study, published in the latest issue of the Proceedings of the National Academy of Sciences, also found that some so-called "African" dog breeds are not really native to Africa. These include Pharaoh hounds and Rhodesian ridgebacks, which turned out to not have much indigenous African ancestry.

On the other hand, "Basenjis are clearly an indigenous sub-Saharan breed, and Afghan hounds and Salukis appear to be indigenous to North Africa or the Middle East," Boyko said.

The pattern seems to be that if a region was colonized or otherwise settled by Europeans, dogs of that area now tend to be less indigenous. Dogs in central Namibia, for example, "looked nearly identical genetically to dogs you would find on the streets of Puerto Rico or in animal shelters in the U.S., a pretty clear indication that these are mixes of various modern breeds."
Robert Wayne, an expert on wolves and dog domestication and a professor in the Department of Ecology and Evolutionary Biology at UCLA, told Discovery News that he supports the new findings.

"It's clear dogs did not originate in sub-Saharan Africa, since wolves are not native to that area," asserts Wayne. However, he agrees that Eurasia is the more likely overall place where dogs were first domesticated, with Egypt being a possibility.
Both Wayne and Boyko hope future genetic research on canines will continue to shed light on the origins of indigenous dog populations to better confirm and pinpoint exactly where the domestication of dogs first happened.


Viegas, Jennifer. 2009. Dog Domestication Likely Began in Africa. Discovery News. Available online:


Why am I interested in this story? Because it involves Basenji's. Basenji's are the only breed that is physiologically incapable of barking. Why is this important? Because, Basenji's greeted Christopher Columbus when he "discovered" the New World. He describes them in his logs:


He went from there in search of the island of Cuba to the south-south-west, to the nearest part of the island, and entered a very beautiful river which was very free from dangerous shoals and other inconveniences. And the water all along the coast there was very deep and very clear as far as the shore. The mouth of the river was 12 fathoms deep and it is quite wide enough to beat about. He anchored inside, he says, at a distance of a lombard shot. The Admiral says that he never saw anything so beautiful, the country around the river being full of trees, beautiful and green and different from ours, with flowers and each with its own kind of fruit. There were many large and small birds which sang very sweetly, and there was a great quantity of palms differing from those in Guinea and from ours. They were of medium height without any bark at the foot and the leaves are very large, with which the Indians cover the houses. The country is very level. The Admiral jumped into the boat and went to land, and approached two houses which he believed to be those of fishermen who fled in fear. In one of the houses they found a dog which never barked and in both houses they found nets made of palm-threads and cords and fish-hooks of horn and harpoons of bone and other fishing materials and many fires (huegos) within and he believed that many persons lived together in each house. He ordered that not one thing should he touched, and thus it was done. The grass was as tall as in Andalusia in the months of April and May. He found much purslain and wild amaranth. He returned to the boat and went up the river a good distance and he says it was such a great pleasure to see that verdure and those groves and the birds that he could not leave them to return. He says that this island is the most beautiful one that eyes have seen, full of very good harbours and deep rivers and it appeared that the sea never rose because the grass on the beach reached almost to the water, which does not usually happen when the sea is rough. Until then he had never found in all those islands that the sea was rough. The island, he says, is filled with very beautiful mountains, although they are not very long but high and all the other land is high like Sicily. It is full of many waters, according to what he was able to understand from the Indians he was taking with him, whom he took in the island of Guanahani, who told him by signs that there are ten large rivers and that with their canoes they cannot go around it in twenty days. When he was going to land with the ships, two rafts or canoes came out and as they saw that the sailors entered the boat and were rowing in order to go and find out the depth of the river so as to know where they could anchor, the canoes fled. The Indians said that in that island there were mines of gold and pearls, and the Admiral saw a good place for them and for mussels which is an indication of them, and the Admiral understood that large ships belonging to the Great Khan came there, and that from there to the mainland it was a ten days' journey. The Admiral named that river and harbour San Salvador."


He weighed the anchors from that harbour and navigated to the west he says, in order to go to the city where it appeared to him from what the Indians said that the King dwelt. One point of the island projected to the north-west six leagues from there, another point projected to the east ten leagues: having gone another league he saw a river not with as wide an entrance as the other which he named the Rio de la Luna. He sailed until the hour of vespers. He saw another river very much larger than the others, and the Indians told him so by signs, and near this river he saw good villages of houses. He named the river the Rio de Mares. He sent the boats to a village to have speech with the Indians, and in one of the boats he sent an Indian from among those he was taking with him, because the Indians already understood them somewhat and showed that they were pleased with the Christians. All the men and women and children fled from these people abandoning the houses with all they had, and the Admiral ordered that nothing would be touched. He says that the houses were more beautiful than those he had seen and he believed that the nearer they approached the mainland the better they were. They were constructed like pavilions, very large, and appeared like royal tents without uniformity of streets, but one here and another there, and within they were very well swept and dean, and their furnishings were arranged in good order. All are built of very beautiful palm branches. They found many statues of women's forms and many heads like masks, very well made. it is not known whether they have them because of their beauty or whether they adore them. There were dogs which never barked. There were small wild birds tamed in their houses. There were wonderful outfits of nets and hooks and fishing implements. They did not touch one thing among them. The Admiral believed that all the Indians on the coast must be fishermen who carry the fish inland, because that island is very large and so beautiful that he could not say too much good of it. He says that he found trees and fruits of a very wonderful taste. And he says that there must be cows and other herds of cattle on this island, because he saw skulls which appeared to him to be skulls of cows. There were large and small birds and the crickets sang all the night, which pleased every one. The breezes were soft and pleasant during all the night, neither cold nor warm. But in regard to the other islands he says that it is very warm upon them and here it is not, but temperate as in May. He attributes the heat of the other islands to their being very level, and to the fact that the wind which blows there is from the south and on that account very warm. The water in those rivers was salt at the mouth. They did not know the sources whence the Indians drank although they had fresh water in their houses. The ships were able to turn around in the river to enter and to go out and they have very good signs or marks. They are seven or eight fathoms deep at the mouth and five within. He says that it appears to him that all that sea must always be as calm as the river of Seville, and the water suitable for the growth of pearls. He found large snails without taste, not like those in Spain. He described the disposition of the river and the harbour which he says above that he named San Salvador, by saying that its mountains are beautiful and high, like the Rock of the Lovers (pena de lo senamorados) and one of them has at the summit another little mount like a beautiful mosque. This river and harbour in which he was at this time, has to the south-east two quite round mountains and to the west-north-west a beautiful level cape which projects outward."


And this opens up a whole other discussion....

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