Dinner and a presentation: An evening with PZ

By PvM

I happened to read PZ’s write-up Local Boy Gets Obnoxious, in which he mentions how he has been interviewed by the Seattle-PI. If I had known PZ was in town, I would have attended the Pacific Science Center talk. Instead I ended up at a Seattle Skeptics “An Evening with PZ MYERS” event. This well attended meetup included a fascinating lecture about the evolution of the eye and introduced me to several aspects of eye evolution with which I had not been familiar.

The story of how science discovered how humans have two “pairs” of eyes, one built around Rhabdomeric photoreceptors and one built around Ciliary photoreceptors. The Ciliary photoreceptors form the photoreceptors which allow us to see, the Rhabdomeric photoreceptors provide another important function, circadian rhythms. What fascinated me is how humans use Cliliary photoreceptors and insects use Rhabdomeric photoreceptors for seeing. And yet, a lovely little worm Platynereis led researchers to understand their common origins.

This is a beautiful story of suspense and solid detective work based around the molecular biology of the eye with many twists and turns and little subplots. Such stories should be written up and presented to students as they show how evolutionary theory leads to further understanding of how life evolved, as opposed to ID Creationism which has no scientific explanations for the origin and the evolution of the eyes. The eye, once seen as an insurmountable argument against evolution, has revealed itself to be a showcase example of evolution, and how science has unraveled these minor mysteries of life.

Sources:

Detlev Arendt, et al Ciliary Photoreceptors with a Vertebrate-Type Opsin in an Invertebrate Brain , Science 29 October 2004: Vol. 306. no. 5697, pp. 869 - 871

And from Russel Fernald’s lab at Stanford

Fernald RD 2006 Casting a genetic light on the evolution of eyes. Science 313:1914-1918

Fernald RD 2004 Eyes: variety, development and evolution. Brain Behav Evol 64:141-147

Fernald RD 2004 Evolving eyes. Int J Dev Biol 48:701-705