However the core hypothesis of the [Neo-]Darwinian theory of evolution is that
… as a consequence to Natural Selection, entailing
Divergence of Character and the Extinction of less-improved forms.
Thus, from the war of nature, from famine and death, the most
exalted object which we are capable of conceiving, namely, the
production of the higher animals, directly follows. There is
grandeur in this view of life, with its several powers, having been
originally breathed by the Creator into a few forms or into one; and
that, whilst this planet has gone cycling on according to the fixed
law of gravity, from so simple a beginning endless forms most
beautiful and most wonderful have been, and are being evolved.
Page 359 , Origin of Species, The - Charles Darwin
In other words it supposes that evolution began with a simple microbe and by the accumulation of many slight gains it eventually produced man. So evidence for evolution must demonstrate the accumulation of functional gains, and conversely evidence of loss of function would be evidence against it.
If you are arguing for mankind to microbes evolution then indeed this would be supporting evidence.