There s a longstanding debate simmering among biologists who study porcupines. There are 16 porcupine species in Central and South America, but only one in the United States and Canada. DNA evidence suggests North America s sole porcupine belongs to a group that originated 10 million years ago, but fossils seem to tell a different story. Some paleontologists think they may have evolved just 2.5 million years ago, at the beginning of the ice ages.
Human activity is making it harder for scientists to interpret oceans' past phys.org - get the latest breaking news, showbiz & celebrity photos, sport news & rumours, viral videos and top stories from phys.org Daily Mail and Mail on Sunday newspapers.
These plants evolved in Florida millions of years ago. They may be gone in decades. phys.org - get the latest breaking news, showbiz & celebrity photos, sport news & rumours, viral videos and top stories from phys.org Daily Mail and Mail on Sunday newspapers.
Fossil study shows frogs were Florida's first-known vertebrates from the Caribbean phys.org - get the latest breaking news, showbiz & celebrity photos, sport news & rumours, viral videos and top stories from phys.org Daily Mail and Mail on Sunday newspapers.