Uploaded April 2026 | Updated September 2026, 1 week ago

---

Smiling is something that humans do. What does it mean? Do animal smiles mean the same as human smiles? Why do humans laugh? Our detectives are getting all the pearly white facts.

Earth Science Investigators sees extra-terrestrial operatives Major Letdown and Private Groupchat, also known as the worst undercover detectives in the universe, find out what is going on around the world.

Subscribe for more at YouTube.com/Channel9