Dee Boersma

On Wednesday’s CBS "Early Show," co-host Maggie Rodriguez teased an upcoming segment on global warming by fretting: "...are penguins sending us warning signs about global warming?" Later, correspondent Debbye Turner talked to biologist Dee Boersma, who claimed that "Well, penguins are the canaries in the coal mine. Penguins are telling us, as marine sentinels, that our southern oceans are…