Some times there are mistakes in nature (for instance, a three legged duck). Sometimes scientists just haven't figured out the evolutionary purpose for certain adaptations. There is an article in this morning's San Francisco Chronicle speculating about the possible reason for the cries certain apes make in the middle of sex since it puts them at risk from predators. As for, are we helpless? Modern medicine can make some amazing changes in "birth defects" yet, if you're born with some abnormality (this is not being being gay!) it might be altered but not eliminated, such as a phsyical handicap of some sort.

Nature makes mistakes at random. But these maistakes can turn out to be beneficial. In genetics they are called loads. A random mutation of a gene might reduce the fitness of the organism, i.e., the oranism and the population of organisms are not operating at full genetic potential. The organism's lack of fitness is a load on the population. Then bam, the environment (either physical or economic) changes and all the least fit are now more fit and the organism that were operating at full genetics potential are now leass fit. If it wasn't for that gene changing the whole population might not perpetuate itself. These are mutational and recessive loads.

Neither.

If you read up on Darwin, you'll learn that he documented 'variations' in nature. Some of these variations turn out to be beneficial enough that their hosts proliferate better, or live longer to breed more than the hosts w/o it. And then the 'variation' becomes the norm.

No mistakes, no errors, no perfection. Everything is an attempt to balance expansion and entropy, order and chaos, creation and destruction. Randomness is built in to the design so that potentially lethal errors can be balanced out by corrections. If it weren't for dung beetles, we'd be up to our eyeballs in shit.

Nature made her biggest mistake when she created human beings, thus ensuring her own destruction!

I don't think it is either. I think evolution is a random crap shoot. Species who don't have the ability to adapt, die off. Those that have adaptability like the cockroach live to see millions of species born and die and yet remain. When you look at the next roach in your kitchen, remember he lived in the dinosaurs' kitchen as well. You can't say the same of our ancestors!

It is too early to know if humans are the last stage of adaptation of our species. We certainly are different even from our grandparents' generation. We are taller, fatter, less suseptible to many of the diseases that killed them, live longer. Part of adaptation is developing tools and techniques to deal with the environment. In my lifetime, there have been so many inventions that preserve or lengthen life and some that even can change it entirely ... if we choose to go in that direction. I have seen many species die off. You know, I haven't seen an elephant in my back yard for ... well for almost forever. You think they are still around somewhere?

I know mistakes do occur. I have an eight-track and a VCR in my storage space to prove that point!

Nature really isn't in a position to make "calculated choices," since that would imply consciousness and an intelligence to nature--as well as some "mechanism" through which it might act.

As far as we know, nature does not possess any of those faculties.

Now, about nature "making mistakes"...again, this implies that there is some "golden path" that nature should be following (or should, somehow, "know enough" to be following?). Sure, you can call the platypus a mistake, but I think it really reflects the viewer's own point of view more than anyone else.

Would you consider the dinosaurs mistakes? They did roam the earth for about 63 MILLION years! We, as humans, should only do so well!