|MadSci Network: Evolution|
Dear Sir: Your question is really outside my area of expertise, but I will answer it as well as I can. Part of the answer is that most of Gondwanaland did not experience 6 months of darkness. That condition only holds quite close to the poles. Gondwanaland was large, and most of the continent never experienced multi-day darkness. I do not know exactly how bright the moon was when it was closer to the earth in the geologic past, nor exactly how much light plants need. However, my feeling is that even a much brighter moon would not have been sufficient to support photosynthesis. I believe that you could find out from a plant physiologist how much light plants need, and from an astronomer how bright the moon has been. These two facts would show whether my assessment is correct. Remember though that most plants absorb light at some wavelengths more readily than at others. Moonlight is probably not as useful as sunlight. If there was a time and place in which plants got by on reflected light from the moon I would expect an unusual flora. the Gondwana flora was lush and does not seem to me to show evidence of survival with limited light. Best Regards, David Kopaska-Merkel Geological Survey of Alabama PO Box 869999 Tuscaloosa AL 35486-6999 (205) 349-2852
Try the links in the MadSci Library for more information on Evolution.