So in what sense are they poorly designed precisely? I"m not asking for a repetition of what you have written. I’m just wondering why you say this is poorly designed? It sounds like it might be optimally designed from a less than optimal starting point. That is not semantically equivalent to “bad design.”
Also, there may be some big advantages to having the retina wired this way. Let me offer a few alternate hypotheses.
It is not clear that this “backward” configuration actually is less efficient at capturing light. What papers are their that demonstrate this? The lengths involved here are are tiny, and cells are transparent (except for the pigment). Do you have any references that can demonstrate that this is suboptimal for collecting light? How was that experimentally tested?
One possible advantages of requiring light to go through cell bodies (the backwards wiring) before collection is that it enables evolution to tune the wavelengths of cells by putting different pigments in cellular vesicles. This is much more important for land vertebrates than water-bound octopi, who do not have as a wide a range of wavelengths to perceive. Given how important vision is to, for example, mammals. It is not clear that the octopi eye could reach the same level of tuning required for colored site as we see in mammals.
I understand your hypothesis, that the “verted” retinal can pack tightly, but it is not clear to me why a mammal retinal couldn’t be packed tight. Can you show me the papers demonstrating that this is the case? Also, the tapetum lucidum is an another interesting case where the biophysics is really important to understand. It very well may be possible that this is an easy way of increasing the sensitivity of the “backwards” retina, but not the octopi retina, which would then explain why the more tight packing of vertebrate eyes is not common.
I"m not trying to be difficult here. I think some of what you have written are reasonable hypotheses. However, that is far from certain. I’m not sure if they have been demonstrate correct over alternate hypothesis yet. Do you know if they have been? What citations do you have?
I want to be clear that I am NOT calling you out @NLENTS, so please don’t take this personally. I’m just not sure that the string of facts here are actually known to be true scientifically. There are alternate hypotheses, and it is not clear which hypothesis is correct. In each case, it might be:
You actually are correct, and this is actually demonstrated in the literature.
You may or may not be correct, but it is not demonstrated in the literature.
You are just not correct, and the opposite is demonstrated in the literature.
The challenging problem, for me, as a scientist, is that this ends up being a very complicated morass to sort out. the argument ends up raising far more questions than it answers, almost like a Gish Gallop. For the argument to work, we have to be dismissive of these questions. However, science doesn’t work that way. We care about those questions, and we know our intuitions on how they will be answered are often wrong.
That is why calling them “Mysteries” is, in my view, far more accurate and true to science.