America is as much of a melting pot for dogs as it is for their human friends. Walk through any dog park and you'll find a range of breeds from Europe, Asia, even Australia and mutts and mixes of every kind.
But a few indigenous breeds in North America have a purer pedigree — at least one has genetic roots in the continent that stretch back 1,000 years or more, according to a new study. These modern North American breeds — including that current urban darling, the Chihuahua — descended from the continent's original canine inhabitants and have not mixed much with European breeds.
A file photo from 2011 shows a man touching a giant bronze sculpture of a mammoth in the Siberian city of Khanty-Mansiysk. A team of Russian and South Korean scientists who found a well-preserved frozen woolly mammoth carcass this month say it also included blood.
Credit Natalia Kolesnikova / AFP/Getty Images
Scientists in Siberia say they've extracted blood samples from the carcass of a 10,000-year-old woolly mammoth, reviving speculation that a clone of the extinct animal might someday walk the earth, if scientists are able to find living cells. But researchers say the find, which also included well-preserved muscle tissue, must be studied further to know its potential.