The reality is that there are very few places on earth that haven't been altered by humans. In Galveston, Texas, coyotes dubbed "ghost wolves" carry high amounts of red wolf DNA. Scientists consider whether their genetic material could save the few red wolves that are left in captivity. Across the country, groups consider whether they'll welcome American Chestnut trees that are engineered with a wheat gene to resist the blight that nearly wiped out their existence.