Pictures and video for a Sunday afternoon.

Source. A reader pointed me to a second composite image of a "global human." It is "a composite itself from four composite of Northwest European, South & West Asian, East Asian and African faces..."

As I said in the comments at Razib's blog: "My, that is one attractive fellow. He looks decidedly Hispanic to me, which I suppose shouldn't be surprising since Hispanics are already highly mixed people with Asian, African, and European ancestry. However, if you squint, he can look a bit Indian (or Italian, or mulatto, or hapa, or…)." I think the thought exercise here is less what the guy actually looks like, but more what we as individuals see in him.

Source. To correct [people's misinterpretations about the relative size of Africa due to maps using the Mercator projection], Kai Krause has created this map and associated information to show that Africa's total area is almost the same as that of the United States, China, India, Japan and all of Europe combined.

I learned about the faults of Mercator projections when I was pretty young, although I can't remember where I learned it. I think it was something I saw on television. My young brain couldn't quite wrap itself around the geometry involved, but I got the major point. Many maps use a system that, instead of staying true to the curvature of the earth, lay things out in such a way that the lines of latitude and longitude make rectangles instead of curved lines. This is mainly for ship navigation and the like, but it has the unfortunate effect of exaggerating land masses at the poles and diminishing land masses near the equator, such as central America, Africa, and India. In the Mercator projection, Africa looks to be only slightly larger than Greenland! If you've ever looked at a globe (I had a globe when I was a kid, which helped me with the geometry of this issue a bit), you know that's definitely not true. The original blog post has more detailed info on Mercator projections if you're interested.

Source. Myotonia congenita, or congenital myotonia is a skeletal muscle-locking disorder. In affected individuals, when the muscles contract, they do not immediately relax again: for a short period the affected muscles stiffen. If the individuals are standing up, they'll fall over, as the kittens in the video do.

I felt bad watching this video. Every time a kitten would fall down, my immediate instinct was to laugh, but then I wanted to cry. I had a very conflicting experience to say the least. The blog post accompanying this video has a really great explanation of the physiology involved in the disease; I suggest you check that out as well.