Posted: May 03, 2020 11:06 am
laklak wrote:Lol. YOUR explanation is so much better, eh?
Cmon, let's see all those peer reviewed papers that explain how Sky Daddy magicked it all. Show your work. Sauce for ganders and such like.
Lol again.
I will refer you to this research on the eye: Simple Eyes Of Only Two Cells Guide Marine Zooplankton To The Light
https://www.sciencedaily.com/releases/2 ... 140705.htm
The simplest of all eyes, on the larvae of marine ragworms, consist of just two cells. They are a photoreceptor cell and a pigment cell that confers the directional sensitivity to light. It absorbs light and casts a shadow over the photoreceptor. The larvae can sense both the presence and rough direction of light that allows for their movement towards light (i.e phototaxis).
However, crucial to all this is the nerve connecting the photorecptor to the cilia:
The scientists found that a nerve connects the photoreceptor cell of the eyespot and the cells that bring about the swimming motion of the larvae. The photoreceptor detects light and converts it into an electrical signal that travels down its neural projection, which makes a connection with a band of cells endowed with cilia. These cilia - thin, hair-like projections - beat to displace water and bring about movement.
This confirms my own understanding:
1. An eye requires more than just a photoreceptor. It needs another cell to detect the direction of the source of light.
2. A nerve must connect the photorecptor to a locomotive apparatus, like the cilium, to permit a reflex action in response.
If these were not present, then a single photoreceptor would not itself have been useful enough to be preserved.