They are all of long extinct creatures too, nothing that was alive 5,000 years ago. (religion.blogs.cnn.com)
Not only are the causes of extinction different, the time frame and the role that extinct creatures played in their ecosystem varies greatly. (treehugger.com)
UNEARTHED Evidence from South American fossils of extinct creatures such as Glyptodon, a giant relative of armadillos, ultimately helped Charles Darwin develop his theory of evolution. (sciencenews.org)