I remember having read that Earth's atmosphere in the time of the dinos had a chemical composition toxic to humans. Therefore forgetting the stuff about time travel wouldn't Terra Nova had to have been enclosed in a dome? With its own oxygen supply. And the humans having to wear oxygen tanks to move around outside?
shareIf this is the case, it's not very well known. Why complicate it? As you pointed out, suspension of disbelief is already required for time travel.
shareI believe it was the oxygen levels back then was higher than it is now. As time went on, the oxygen levels came down to where it could sustain us. Too much of one thing isn't good for our bodies.
shareThe atmosphere back then was oxygen rich but by no means toxic to humans. If you hyperventilate you might pass out and you'd wake up with a hell of a headache but just keep a paper bag handy to breathe into and you'll be fine!
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