If mosquitoes used Yelp, they might look for their next meal by searching nearby for a heavy-breathing human with Type O blood, sporting a red shirt and more than a smattering of skin bacteria. Preferably either pregnant or holding a beer.
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 β 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 β including that current urban darling, the Chihuahua β descended from the continent's original canine inhabitants and have not mixed much with European breeds.