<html><head><meta http-equiv="content-type" content="text/html; charset=utf-8"></head><body dir="auto">The blindspot evolved not because of some ancestors stared at the sun — or so it seems because all vertebrates have it and cephalopods (which have very similar eyes otherwise) don’t. So something early in evolution — before vertebrates made it to the land — took the blindspot path. Most likely it was a developmental constraint rather than anything to do with looking directly at the sun. (Add to this, looking directly at the sun now with no eye protection can lead to retinal damage. I’m not sure how much difference it makes have the retina behind some thin blood vessels... And behind the blindspot itself — even if that is more protected — is, well, blind, no?;)<br><br>I like that frog jumping thing. Reminds of the (a tad overblown) saying in space exploration that Earth orbit is halfway to anywhere in the universe.<br><br><div id="AppleMailSignature" dir="ltr"><div style="line-height: normal;"><div style="line-height: normal;"><span style="line-height: 20px; background-color: rgba(255, 255, 255, 0);">Regards,</span></div><div style="line-height: normal;"><span style="line-height: 20px; background-color: rgba(255, 255, 255, 0);"><br></span></div><div><div style="line-height: normal;"><span style="line-height: 20px; background-color: rgba(255, 255, 255, 0);">Dan</span></div><div style="line-height: normal;"><span style="line-height: 20px; background-color: rgba(255, 255, 255, 0);"> Sample my Kindle books at:</span></div><div style="line-height: normal;"><p style="margin: 0px; font-stretch: normal; font-size: 12px; line-height: normal; font-family: Helvetica;"><span style="font-size: 12pt;"><a href="http://author.to/DanUst">http://author.to/DanUst</a></span></p></div></div></div><div><div style="line-height: normal;"></div></div></div><div dir="ltr"><br>On Jul 21, 2019, at 9:52 AM, William Flynn Wallace <<a href="mailto:foozler83@gmail.com">foozler83@gmail.com</a>> wrote:<br><br></div><blockquote type="cite"><div dir="ltr"><div dir="ltr"><div class="gmail_default" style="font-family:comic sans ms,sans-serif;font-size:small;color:#000000">Well, John, that's a lot of interesting information and no joke.</div><div class="gmail_default" style="font-family:comic sans ms,sans-serif;font-size:small;color:#000000"><br></div><div class="gmail_default" style="font-family:comic sans ms,sans-serif;font-size:small;color:#000000">The eye - is it possible that if strong sunlight were to aim directly at retinal cells it would be too strong? If so, then it's not backwards. It's a necessary filter. (I don't mean looking directly at the sun, but just, say, light bounced off a white building, or a strong fire.)</div><div class="gmail_default" style="font-family:comic sans ms,sans-serif;font-size:small;color:#000000"><br></div><div class="gmail_default" style="font-family:comic sans ms,sans-serif;font-size:small;color:#000000">Your last paragraph reminds me of a metaphor I invented a while back: there are two frogs - one can make a vertical leap of 5 inches and the other 6 inches. Both are presented with stairs that are 6 inches high. One can go to the top and the other cannot go anywhere. Perhaps a difference this small is what separates us from the other apes.</div><div class="gmail_default" style="font-family:comic sans ms,sans-serif;font-size:small;color:#000000"><br></div><div class="gmail_default" style="font-family:comic sans ms,sans-serif;font-size:small;color:#000000">bill w</div></div></div></blockquote></body></html>