Evolution (in particular genetic coding) also fails to explain how the body plan is formed. Simply producing proteins is insufficient.
Another of the many problems with evolution is the part about transition from one species to another. It’s never been observed. And if you have an intuition for probability, you might see that for evolution to be true there would have to be a whole lot more transitional species—not just fossils of transitional species, but currently existing transitional species.
Like you say, speciation is one of the key points of contention with evolution, because it’s never been directly observed. That, however, is probably due to the extreme time span which is required for it to happen. Simpler adaption is not in dispute. But speciation is just adaption over a much longer timeframe. When two members of the same species adapt differently under separate environments to the point where they can no longer breed with one another, speciation occurs.
No, you also have to produce fats and sugars.
If you want to know how the body plan is formed, look up embryonic development. First, the fertilized ovum grows. Then, at about 3 weeks, all of the organs start to form and all exist by 5 weeks, along with the limbs. This is all a result of cells producing and responding to chemical signals. After 5 weeks, the body grows and becomes more detailed.
Another of the many problems with evolution is the part about transition from one species to another. Its never been observed. And if you have an intuition for probability, you might see that for evolution to be true there would have to be a whole lot more transitional speciesnot just fossils of transitional species, but currently existing transitional species.
There are transitional species all around you. Considering that evolution is a continuous process, then, by definition, all species are transitional. Also, there exist living organisms at every "stage" of evolution--from simple colonies of identical but communal cells, through every level of complexity until you get to what we usually think of as the most complex organisms.
If you have ever noticed that children do not look exactly like their parents or each other, you have noticed a consequence of evolutionary forces at work.
We ourselves could well be transitional species. We may be transiting from corporeal to spiritual beings. God can do anything.