No because a function is lost.
It's just this simple,let's say the offspring loses an arm due to a mutation what could the offspring gain from the mutation that would benefit the offspring ?
Can a human benefit from the loss of any function ? and what function would be a benefit this person that lost a function ?
Actually, you are absolutely wrong about that. Mutations are ubiquitous. Every human being (you included) has between 100 and 200 unique new mutations. I guess the Charlatans at the Discovery Institute forgot to teach you that.
The sickle-cell anemia mutation occurs at the rate of about 10^-5 per generation. If that mutation occurs in a human living in a region where Malaria is prevalent, it will beneficially protect that person (and any descendents) from Malaria.
That said, this is only a minor, almost irrelevant example of the role of mutation in evolution. The primary role of mutations is to increase genetic variability.
All 200 or so of your personal mutations are point mutations on your DNA, i.e. a change to a single base pair in a single DNA codon. If they occur on a length of DNA that is actually a gene (as opposed to “junk DNA”
These variations in our proteins are the expression of our genetic variability as a species. They are the reason that we come in different shapes, sizes, colors and all the other differences in our bodies and abilities. And this variation is the raw material upon which natural selection acts. If it is beneficial to be taller, then natural selection will favor those variations that increase height and eliminate those that reduce it.
But the eliminated variations are constantly being replenished by each generation’s new mutations. This includes some mutations that will reduce height (and be eliminated quickly) and some mutations that will increase height, even beyond the original variation of the population. In this way, over time, organisms can evolve completely beyond the limitations of their original variation. This is how mutation creates genetic novelty.
Do a bit of research and you will find that over the last several decades, the average height of the Japanese youngster has increased dramatically. The children often tower over the parents.