Why do scientists interfere with what Mother Nature has designed?

We know that some hybrids occur in nature (Coywolf,Gizzly-Polar,Whalepin,etc) and we know that man-made hybirds have been created. Is it possible that man’s encroachment on wilderness habitat has forced these ‘wild’ hybrids to occur?”

Do you agree with the argument that it’s “Natures Way” for these hybrids to occur, in spite of the fact that some of these hybridizations create infertile offspring? Does that fact that some of the hybrids are fertile mean that this is nature attempting to find a balance?

Do you agree with scientists assessments that these hybrids somehow threaten the genetic pool of the parent species or would you argue that this is evolution in action? Do you agree with the idea of eliminating hybrids as a threat to genetic purity?