Of course crabs feel pain. So do fish and birds, snakes and antelopes. They all feel physical pain. What they don't do is *suffer the pain*, in the same psychic and emotional sense that humans do. They are not self aware.

Good post. But - CO2 is NOT driving temp increases, it is NOT a pollutant, and it is NOT a problem that we need to solve.

The current quantity of atmospheric CO2 is not far above the starvation level for plants, and it is lower now than it has been for virtually all of the last 500 million years.

Here's the science:
http://www.sydneyminingclub.org/presentations/2008/november/plimer/player.html