The act of twerking on a tree. You can do it with your feet on the tree, or you could just twerk on it. It's a fun thing to do with friends or just by yourself.
Please don't twerk on other people's trees. That is their twerking tree. How would you feel if you looked out the window and saw someone twerking on your tree? It's not nice. Find you own tree and twerk on it. #TreeTwerkin

The safeguarding of Earth and other worlds from biological cross-contamination (i.e. billionaires with too much time on their hands).

Also known as “planetary protection.” Planetary protection / quarantine “reflects both the unknown nature of the space environment and the desire of the scientific community to preserve the pristine nature of celestial bodies until they can be studied in detail.”

There are two types of interplanetary contamination. Forward contamination is the transfer of viable organisms from Earth to another celestial body. Back contamination is the transfer of extraterrestrial organisms, if such exist, back to the Earth's biosphere.