the way i see it (and a few billion others) is that it is impossible for all this diversity to come from a common ancestor,and without god, where does the new information come from to turn a single cell into a human or an avocado tree,?
Again, dispense with the "know" idea. You're basing this argument on the idea that "nature needs to know new information in order to make changes."
That's not how it works.
you say "it just did it because it needed it" but how?
The descendants of any one ancestor are not identical - each has different traits. If none of those traits affect survival, all are equally likely to pass on their genes. If some traits help survival, those are more likely to continue being passed on, and if some hurt survival, those are less likely to be passed on. Any organism that carries genes that promote survival will be more likely to live longer and procreate more often, and those that carry genes that inhibit survival will be less likely to live longer and will procreate less. Over time, the trait that inhibits survival will generally disappear or, at the least, become an infrequently inherited trait.
THAT is how "natural selection" works. Nature doesn't consciously select anything. It happens naturally in the course of birth, life, survival, and death.
With fruit trees. Let's not even consider the artificial manipulation that humans have subjected fruit trees to in order to produce better fruit. Let's simply consider the wild banana that was pictured earlier. The fruit itself carries the seeds for future generations of banana trees. By itself, the fruit and seeds will simply, eventually, fall off the tree, rot in the ground, and potentially become a new tree. Problem is, if this happens with all the fruit, there will be a lot of closely clustered new growths near the original tree, and not all of those will survive. The competition for resources will be fierce (water, soil nutrients, sunlight, etc.) and it may be that
none will survive because the original tree, being mature already, will overshadow the saplings and prevent them from growing (those banana trees have large leaves - and that's another survival trait, incidentally). If the tree continues to produce that kind of fruit, it won't pass on its genetics to any viable trees. So long as the fruit continues to fall just around the tree, future saplings will continue to deplete the soil of its nutrients, continue to compete with each other and the mature tree, etc. etc. That banana tree won't produce a huge population of future banana trees.
But say the fruit happens to be edible. Now, the tree doesn't
know that the fruit is edible, nor does it consciously
make the fruit edible, nor does any other entity consciously decide "let's make this fruit edible." But it
is edible. Rodents and birds thrive on edible fruit. When one of them eats one of these wild bananas, it tends to eat both the fruit and the seeds. (It is important to note again the fruit is
not designed to be edible by others. The fruit contains the nutrients needed for the seeds to start growing when they are deposited in the soil, in the absence of any other nutrients being available at the outset.) The bird or rodent doesn't stay put - they move. They keep eating more fruits and keep moving. Eventually they eliminate their waste somewhere, generally
not right around the original tree. The fruit is digestible, the seeds are not. They generally pass through undigested, and the waste plus seeds generally are deposited in soil somewhere. Now the seeds can grow in a
new area. They've been spread out. This tends to be more beneficial in terms of the new trees' survival into maturity, to the point where
they can produce similar fruits, and so it goes, on and on.
This is the same way that natural selection works with animals. One can look at cheetahs and antelopes, for example. The key trait here is speed. Antelopes that are faster than others will outrun the cheetahs, leaving the slower ones behind, and the faster antelopes survive longer to pass on their "faster" genes. Cheetahs that are faster will more likley catch the faster antelopes, and be more likely to eat enough to survive longer and pass on their "faster" genes. Cheetahs weed out the slower antelopes, which has the effect of promoting faster generations of antelopes later. Faster antelopes weed out the slower cheetahs, who are less able to eat enough to survive. No one is directing this consciously, any more than you need to consciously regulate your heart or digestion. It simply happens.
