The twin role played by the skin – protection from excessive UV radiation and absorption of enough sunlight to trigger the production of vitamin D – means that people living in the lower latitudes, close to the Equator, with intense UV radiation, have developed darker skin to protect them from the damaging effects of UV radiation. In contrast, those living in the higher latitudes, closer to the Poles, have developed fair skin to maximize vitamin D production.
A global atlas of skin color.
The Veins And Muscles Of The Arm (16th century) by Leonardo da Vinci
Lateral radiograph illustrating articulation of the knee joint
The human knee is a massively complicated system of muscles, bone articulations, tendons, ligaments, and bursae. Given that over 300% of the body weight is exerted upon the knee when you’re doing nothing more than walking (and nearly 600% while running), is it any surprise that it’s the most common joint needing operation?
Atlas for Electro-diagnosis and Therapeutics. F. Miramond de LaRoquette, translated from German by Mary Gregson Cheetham, 1920.
1. Studies of the arm showing the movements made by the biceps (c. 1510)
2. Studies of the muscles of the neck, shoulder, chest and arm (c. 1509-10)
3. View of a skull (c. 1489)
This is produced by a hand drawn photogram on top of a medium format photo.
DO YOU HAVE BONES?
DO YOU USE THEM?
DO YOU WANT TO KNOW ABOUT THOSE BONES THAT YOU HAVE AND USE?
Cro-Magnon, early modern homo sapiens, skull ca. 35,000 BP
To obtain a true and perfect knowledge [of the vascular system] I have dissected more than ten human bodies, destroying all the other members, and removing the very minutest particles of the flesh by which these veins are surrounded. And as one single body would not last so long, since it was necessary to proceed with several bodies by degrees, until I came to an end and had a complete knowledge; this I repeated twice, to learn the differences…