New Zealand Tree Stuck In Evolutionary Time Warp
sciencehabit writes "A eucalyptus-like tree from New Zealand is still waging a battle that should have ended over 500 years ago. The tree continues to sport evolutionary adaptations, such as barbed leaves, to protect it from a large, flightless bird known as a moa. There's just one problem: the moa went extinct around 1500 AD."
And humans still have tailbones.
You're assuming that the human appendix is useless, which isn't necessarily the case. There are at least two open suggestions as to its function.