Posted on 12/12/2010 6:29:46 PM PST by decimon
The Egyptian vulture population of the Canary Islands was established following the arrival of the first human settlers who brought livestock to the islands. A genetic comparison of Iberian and Canarian birds, published in the open access journal BMC Evolutionary Biology, found that the Egyptian vulture population in the Canary Islands was likely established around 2500 years ago around the same time as humans began to colonise the islands.
Rosa Agudo worked with a team of researchers from the Doñana Biological Station, Seville, Spain, to investigate genetic and morphological changes between 143 Iberian birds and 242 from Fuerteventura, one of the Canary Islands. She said, "We found that the island vultures are significantly heavier and larger than those from Iberia. The establishment of this insular population took place some 2500 years ago, matching the date of human colonization. Our results suggest that human activity can trigger divergent evolution and that this process may take place on a relatively brief time scale".
The authors suggest that before the arrival of humans, the Canary Islands would not have been able to support vultures, as food resources would have been scarce, consisting only of the remains of seabirds and sea mammals, or of rodents. They say, "The introduction of new and abundant food sources by humans could have allowed not only colonization by vultures, but also their demographic expansion and their putative adaptation to the new island environment". For once, human activity has actually assisted in the diversification and adaptation of the Egyptian vulture, now globally threatened and classified as 'Endangered' on the IUCN Red List.
Once upon a time ping.
I guess that similar may have occurred many times in many places.
I’m getting bored. And more bored. And Zzzzzzzzzzz.
The old timers tell me that there used to be a lot fewer deer here in southern michigan. Big farms and widlife management has caused their numbers to explode.
· join list or digest · view topics · view or post blog · bookmark · post a topic · subscribe · |
|||
Antiquity Journal & archive Archaeologica Archaeology Archaeology Channel BAR Bronze Age Forum Discover Dogpile Eurekalert LiveScience Mirabilis.ca Nat Geographic PhysOrg Science Daily Science News Texas AM Yahoo Excerpt, or Link only? |
|
||
· Science topic · science keyword · Books/Literature topic · pages keyword · |
ferinstance.
Did you mean:
"I'm yawning. I'm yawning some more. Zzzzzzzz"?
Unanswered is the question of whether they were introduced deliberately, perhaps as a religious totem or as a means of keeping dead animals cleaned up, or were colonized by the vultures themselves.
Disclaimer: Opinions posted on Free Republic are those of the individual posters and do not necessarily represent the opinion of Free Republic or its management. All materials posted herein are protected by copyright law and the exemption for fair use of copyrighted works.