Genetic Study may Track Dogs' Travels with Humans

A genetic study of a sexually transmitted canine cancer has offered clues to how dogs may have traveled around the world with their humans. Scientists analyzed the DNA of 440 nine tumors that exist today. Additional mutation allowed the scientists to trace the tumor's family tree. 

The research estimated the time since the mitochondrial transfer events by counting the number of mutations. One of them really seems to just track around maritime trade routes, in the last few hundred years. We found it along the coast of West Africa, in the Cape Vede Islands, Brazil, South Africa, India and some parts of southern Europe.

Head of Brazilian frogs are venomous wepeons

It's no surprise that some frogs secrete poison from glands in their skin. But researchers have discovered the first two species of frog, both living in Brazil, that are actually venomous. Not only do the frogs produce potent toxins, but they also have a mechanism to deliver those harmful secretions into another animal using bony spines on their heads.

Brazilian Frogs

Source: Science Daily