The first ascent was made by a climber/physician who--I'm purely speculating here--noted the resemblance between a climber on Homunculus and the popular graphic depicting a homunculus. For a homunculus is a thing.
It is an area of the cerebral cortex dedicated to sensing and moving different parts of the body. The graphic is a map showing what areas of the cortex are associated with the various body parts. The disproportionate sizes of body parts in the graphic represent the number of neurons dedicated to them. As you can see, the hands and face are pretty big. There are a large number of sensory and motor neurons innervating those areas. Makes sense: we need a lot of sensitivity and control in our mouths and hands to manipulate, masticate, and communicate.
It's hard to see in this graphic, but it's also true that the toes and feet take up as much real estate in the homunculus as the entire trunk and neck put together. Why would that be? If you've been through the Rolfing® Structural Integration Ten Series, you may recall Session #2 and it's focus on the feet and lower legs. You may also recall the increased connection with the ground and improved balance you experienced after the session. Your feet and toes felt alive.
When we esconce our feet inside protective shoes, we blunt the sensations those richly innervated appendages crave: our primary physical connection with the environment has historically occurred through our feet. The millions of nerve impulses traveling between the feet and the homunculus enable us to stand upright, balance on one foot, push off while throwing a spear, and chase down an antelope. That's why it feels so good to awaken the sensations of our feet, and probably why so many of us love receiving foot massages. Those nerves thrive on stimulation.
So, next time you wiggle your feet in the sand or tickle the bottoms of your feet with blades of grass (although not likely in California!), imagine that area of your homunculus lighting up. I will continue to daydream about that other Homunculus and imagine myself as the little figure with huge hands and feet splayed on its brainy underside.