Do you have an example of a change to an entirely different species in a single generation?
Yes, many forms of domesticates are produced this way. It's a common method of producing ornamental plants. Diploid versions are altered to produce tetraploids which can no longer breed with diploids. Off the top of my head, I could name daylilies, rhododendrons, spireas, durum wheat etc.
This occurs in the wild mostly with plants but has been known to occur in animals.