How about citing some references to prove your point.  I believe that your understanding that 'the earth's climate has been changing for 4.5 Billion years, without the help of humans' is completely wrong.  With the appearance of humanity, whole species of animals have disappeared, forests [trees which we need for oxygen] have been destroyed.  Since the Industrial Revolution, the climate is warming badly.  Here are a few of my references which counter your points.
-------------------------------
Bill McKibben, THE END OF NATURE [New York: Random House, 2006].
Bill McKibben, EAARTH, [New York: St. Martin's Griffin, 2011].
James Nash, LOVING NATURE, [Nashville: Abingdon Press, 1991].
Jared Diamond, COLLAPSE [New York: Penguin Press, 2005].
David Loy, "The Religion of the Market," in Coward and Maguire, VISIONS OF A NEW 
                       EARTH, p.15-28.

See www.iuch.org [International Union for Conservation of Nature] to keep track of lists of extinct and endangered species.