Evolutionitwits love to use the phrase "descent with modification" when talking about their "theory".
They say that you are a modified version of your parents, thinking that proves
However when pressed they never say what gets modified.
Sure they will give very vague answers like "the DNA gets modified" or "the existing structures get modified", but never do they tell us any details.
And that is because they don't have any idea whether or not the transformation required are even possible.
Take for example the human foot.
It is very different than all other extant primate feet.
No one knows whether or not the human foot could "evolve" from a non-human foot with an opposable big toe.
This year is the 150th anniversary for the release of Charles Darwin's "On the Origin of Species" and we still don't have any idea if those transformations are even possible.
There isn't any genetic gata which we could use to test that premise of descent with modification can lead to the diversity of life from some unknown population(s) of single-celled organisms.
Yet the "theory" of evolution is considered scientific.