your system is better described as did darwin, descent with modifications. evolution draws at least two more principles out of an examination of the world of life. 1-common ancestor, i think it is an axiom, but i am open to modification of this. assumption that there was 1 primorial organism from which all life as we know it, both alife now and in the fossil record descended.
you can not derived common ancestor from your 3 principles. "birth death and slight differences"
2-and something about the sufficency of modification to cause all the various forms of life we see. this principle is not universally accepted in the scientific world. sufficency of random mutations plus natural selection is more like a tendative working assumption.
without these two additional ideas your system is not evolution. but some much weaker form of descent with modifications.
richard williams
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