The following comes from a rudimentary understanding of DNA and biology. Correct me if I have wrong assumptions. Each cell of an organism contains the same set of DNA as all the other cells of the body. Exceptions occur from imperfect copying but these are pathological. Since not all cells are identical, so there exists some process whereby the same DNA functions differently to produce different kinds of cells. However, at some level we can identify sets of cells which are for all practical purposes identical. Maybe, for example, all human femur bone cells are identical. Or maybe within the femur the cells at one end are different than the cells at the other. However, at some level, large compared to the size of an individual cell, the cells are all identical to their neighbors. Consider such a section of tissue. It has a morphology, a shape that is essential to its proper function. Whatever this shape is, at the scale of an individual cell, the shape cannot be "known." If we speak for a moment as if the cell has a brain and that brain is following the instructions of the DNA "map", I don't see how the cell can "know" how to behave relative to its neighbors in such a way that they collectively produce the necessary large scale shape. Because the cell can only "know" what its nearest neighbors are doing. It doesn't "know" where it is in the overall shape it is working to produce. Even if each cell had a map of the organ detailing the specific role of every cell in that organ, it would be impossible for the cell to be able identify on the map which cell it corresponds to. And each cell has the same instructions as every other cell. There is no central director communicating separate instructions to the cells. Take a femur for instance. Bone cells on the surface of a femur might be able to "know" they are on the surface of the bone and so they don't reproduce in such a way that the bone would grow deformed. But how do the cells on the ball of the femur know to arrange themselves nearly spherically while those on the shaft of the femur are arranged nearly cylindrically. They can't possibly know that. And there is no central director with a "big picture" telling them how to do it. So I don't see how in principle that DNA alone can determine gross morphology. If anyone here can explain it, I'd be very interested.