Names of Monkey Sounds

I saw this study the other day that played the sounds that monkey's make to other monkeys. The sounds were scientifically labeled: "coos, grunts, barks, and harmonic arches." I thought that "harmonic arch" probably isn't what the monkey had meant to say!
There is an even more extensive list in this paper Y. E. Cohen 2006, but I have censored it for the general public . . . you'll know why if you look it up.


Photo courtesy of link

Optical Brightness Illusions, and Hazyness

These optical illusions are so great that they have the privilege of gracing my new wall.

The gray Diamonds are all the same shade of brightness.
Note the much stronger effect in the upper one.

The gray rectangles inside are the same shade of brightness.


Below is my current all time favorite.

The two inside diamonds are identical.

Unlike the normal illusions of brightness, this time one of the diamonds appears "Hazy" quite an impressive feat. It takes some nuance to explain why this happens (E. H. Adelson 2000), but the other illusions are easily explained by the similar illusion below:

If you were to see this in real life, the actual reflectance of B would be lighter than A, and so your brain computes this and tells you that its brighter even though on the screen they have the same brightness.

These are fake-motion drawings: