Here’s a useful book that, besides teaching you science, promises to be a potent creationism-killer: it’s Evolution’s Witness: How Eyes Evolved, by Ivan R. Schwab. Sadly, it’s $50, even with the $25 discount on Amazon, but you can look inside for free, and maybe ask your library to order it. It’s published by Oxford University Press, which has a record for high-quality books like this.
Remember that eyes have evolved anywhere between 40 and 60 times in animals, though the physical structure can reflect a homology of “initiating” genes: PAX6, for instance, is a key gene in initiating eye formation in both mice (and presumably other mammals) as well as fruit flies, even though insect eyes and vertebrate eyes, as structures, evolved independently.
Over at Science 2.0, Hank Campbell interviews Ivan Schwab, the book’s author. Schwab is an M.D.: an ophthamologist at the University of California at Davis who is afflicted with the curiosity of a naturalist. He speculates about when the first eye evolved, and has a unique answer to the perennial and misguided creationist question, “Of what use is half an eye?”
You can also browse through quite a few pages on books.google.com
http://bit.ly/srUcjB
That’s just plain awesome. I am getting this. Maybe we can all share via USPS. lol.
I am halfway through this book, and it is truly excellent. It is especially good at telling the story of how the basic elements of photoreception and spatial vision may have arisen, and at discussing all of the varieties of vision that are found among living creatures. The book is also notable in that it is lavishly illustrated with beautiful diagrams and photomicrographs.
What type of eye is that on the cover? I don’t recall ever seeing one like that before.
b&
Reptile?
Some sort of shark, I think
No tear duct obvious – I suppose that must be a distinguishing characteristic?
I’d go with amphibian of some sort. The shape of the pupil, combined with the scales, but I am no expert in any of this.
Rixaeton’s research material:
Frog specimen for comparison
I’ll bet it wasn’t easy coming up with that particular answer….
Cheers,
b&
Amphibians don’t have scales.
I’d noted the lack of a tear duct too and thought “marine animal”.
Triaenodon obeses….white-tipped reef shark
Aha!
I do believe you’re correct. Thanks!
Beautiful animals, and gorgeous eyes….
Cheers,
b&
I shall have to suggest it to our ophthalmology librarian! Already have a mountain of reading – an impossible task. Just saw a talk by Daniel Kahneman, on his new book Thinking Fast and Slow, on Wednesday evening at the Royal Institution. Very interesting, and a charming, modest man.
PS OUP are certainly discerning publishers. They published WEIT in the UK! 🙂
ooooooo nice. I work with rhodopsin so it should be a nice read.
Not available in the UK for another couple of weeks.
“Of what use is half an eye?”
If the creationist wears glasses I, point out his eyes are not as “good” as mine, then ask if he would be willing to pluck out his less than “perfect” eyes for a laugh.
I sometimes go down the line of pointing out that an eagle has 8 times better accuity than him, ask him what use 1/8th of an eye is and ask if he will pluck out his eyes.
It’s more effective (and amusing) than explaining selective advantages in early ecosystems etc.
Not available on Kindle dammit. My favourite chapter in Life Ascending was the one about the eye so I was really excited when I read the title of this post, sigh, I hate disappointment.