The Harlequin Mantis Shrimp "has the most sophisticated visual system in the world," and may "be able to distinguish up to colors (compared to the seen by human beings).
All Of Earth's Water In A Single Sphere This picture shows the size of a sphere that would contain all of Earth's water in comparison to the size of the Earth. The diameter would be roughly the distance from Salt Lake City, Utah to Topeka, Kansas.
"Feudalism is a social system that existed in Europe during the Middle Ages in which people worked and fought for nobles who gave them protection and the use of land in return"
The system. A 1911 Industrial Worker (IWW newspaper) publication advocating industrial unionism that shows the critique of capitalism. It is based on a flyer of the "Union of Russian Socialists" spread in 1900 and
Feudalism evolved in western Europe, Military elites of the landlord class could afford horses and iron weapons. The greater lords provided protection to lesser lords (vassals) who in return supplied military and other service.
