Claim:  There has never been any creature on the planet with the consumptive power of human beings.  We humans, thanks to our usage of tools and our dominance of the land, have left the biggest 'footprint' of our existence of any creature and thus, have the capability of causing the greatest impact (beneficial or otherwise) to the planet.

Support: There is extensive structural remains of most ancient civilizations, including China, Egypt, Greece, The Romans, hell even the Double Harbor of Carthage (which was utterly destroyed by the Romans) still endures.  I will gladly offer support for this, but I hope we don't have to debate on the existence of ruins from ancient civilizations.

Why do I start with this as my opening statement?

I choose to open with this because our consumption leads to waste and debris and it is my position that this waste and debris will be/is currently harming the planet.  It is a natural by-product of our way of life.  As Cpt Charles Moore says "Only we humans make waste that nature can't process."  This is critical

 We manipulate the environment (like all animals) to our benefit.  However, unlike other animals, we have the powerful tool of technology with which we sculpt the world.  

Roads girdle the globe; the construction of those roads requires man power, and tools and energy source.  As our ability to wield technology grows, so does our ability to affect change on a large scale.

Example 1:

We are seeing the impact of our plastic consumption in the North Pacific Gyre.  Here is Cpt Charles Moore talking about his experience in the gyre (he has led several expeditions

http://www.ted.com/talks/ca pt_charles_moore_on_the_sea s_of_plastic.html

additionally, here is support of Charles Moore's credentials and his claims.

A yachting competition across the Pacific led veteran seafarer Charles Moore to discover what some have since deemed the world's largest "landfill" -- actually a huge water-bound swath of floating plastic garbage the size of two Texases. Trapped in an enormous slow whirlpool called the Pacific Gyre, a mostly stagnant, plankton-rich seascape spun of massive competing air currents, this Great Pacific Garbage Patch in some places outweighs even the surface waters' biomass six-to-one."

 This is also from www.TED.com

This is just one example of the footprint we leave on our planet that our planet is not equipped to deal with.  We create waste that our planet cannot break down; we synthesize chemical processes that do not naturally occur in nature (and therefore cannot be undone by nature).

These things are having a massive impact on the planet already, and we are only 160-200 years into the Industrial Age.  While people may debate about the 'warming' of the planet, they are ignoring something that is utterly irrefutable (although, this is supposed to be a debate, KenTX, so I hope you will try), The waste of man is already affecting the environment of the planet negatively.  Global warming, climate change.  Call it what you like.  It's the by-product of pollution, consumption and negligence coupled with a lack of a sense of responsibility and it can be measured.

Thank you.

-CMN