MaryAM, good one.
We have lots of limestone and coral here in mid-America, left from when this was once a sea bed! (So much for ocean levels rising.)
"Phytoplankton are the largest producer (eater) of CO2"
It is theorized that carbon based fuels are not just ancient fossil based, but are being continually created by millions of tons of dying Phytoplankton falling to unexplorable ocean depths under extreme pressure.
Greenies now are so excited to replicate something similar with algae and call it "sustainable biofuels".
They are getting HUGE government grants for their efforts.
That seems to be similar to being paid to grow "sustainable" grass in your house when you have a whole yard full of it.
Real "settled" Scientists say: "We know so little and we don't know what we don't know."
Born and raised in Indiana - good old Indiana limestone is featured in many buildings in DC and other cities. All the result of the permian extinction. And when Indiana was totally under water and an old sea bed - except for the southern part of the state. As for dying Phytoplankton - one of the biggest producers of O2 on the planet - my greatest fear is the long term effects of Fukushima discharges into the Pacific - totally uncontrolled and uncontrollable - basically Chernobyl on steroids. A major kill off of this organism and we can kiss our butts good by.