Some responses to my posts on the evolution of the eye, made use of the other senses to compensate for any short-comings found in vision during its evolutionary history. I would like to begin showing problems with this idea.

1. Physical sensations are the most underrated of the senses, and is perhaps the most important to our survival. There is an entire world of specialized receptors working in unison to provide us with essential information. There is no single sense for touch, instead we have specialized receptors for pain, for temperature, for stretching, for pressure, for vibrations, etc. The results of not having these sensations is harmful and lethal. There are many reasons why a person might lose these sensations, one of them is diabetes, which leads to neuropathy in the extremities. This makes the individual extremely prone to injury. They cannot tell when their circulation is cut-off. They cannot tell when they’ve cut or bruised themselves. They may ignore injuries that eventually lead to infections or ulcers. These infections can lead to rotting or death if the limb is not amputated.

Seeing how important these sensations are to survival. How did our ancestors avoid death and injury before these sensations evolved?

2. Without your sense of touch, you need vision to compensate. Bodily sensations don’t just inform you about what you’re bumping against in the external world, they tell you what your body is doing internally, how you’re oriented, and how you’re moving. Take Ian Waterman, a person that completely lost these sensations. He cannot do the simplest of actions. He cannot grab an egg without crushing it, he cannot stand and walk without looking, he couldn’t even sit up from his bed because he had no way of feeling his weight distributed. He had to learn to use visual cues to accomplish all these tasks.

If our ancestors relied on touch before the eye evolved properly. What did they rely on before these bodily sensations evolved?