If adaptation improves a species success, why do species go extinct instead of adapting and surviving

Forum Question: This week we learned about some key fossils that help us understand our place in nature. If adaptation improves a species success, why do species go extinct instead of adapting and surviving? Helpful Hint: You may be tempted to write a post including the phrase “survival of the fittest”. This is a commonly misused and misunderstood phrase in describing natural selection and evolution. Scoville (2015) provides an easy, quick read about this issue.

Scoville, H. (2015). Survival of the Fittest? Retrieved from http://evolution.about.com/od/NaturalSelection/a/S…