This has been discussed from various angles before here on ATS.
Have a look here:
During the Carboniferous and Permian periods, atmospheric oxygen concentrations were significantly higher than they are today. Prehistoric insects breathed air that was 31-35% oxygen, as compared to just 21% oxygen in the air you're breathing as you read this. Atmospheric oxygen is the single most limiting factor on insect size.
Originally posted by jazzgul
reply to post by eriktheawful
Still thinking outside the box...
You can create artificial gravity by use of centrifugal force
Is it possible to increase the gravity of the planet by adding that force to??
Originally posted by HeliophantYou may be on to something with some "Body" passing close to earth.
Or maybe a massive body passed near to Earth in the past and the gravity from this other body "pooled up" Earth's seawater to the side facing the passing body. Thinking out loud...
Maybe this happened around the time we got our slow angular wobble... (precesion of the equinoxes)edit on 28-2-2013 by Heliophant because: (no reason given)
Originally posted by eriktheawfulI dont see what ever it was to be a high speed impact. Quite the opposite, it looked very controlled. When I said 300 mile radius, I meant the actual contact area. The thing itself could have been 1500 miles or more in total diameter. Moon perhaps bouncing off Earth before it took up its present location? Any ones guess.
reply to post by All Seeing Eye
Even at 300 miles wide, the impactor would not significantly change either the Earth's orbit, nor our axial tilt.
It can change our length of day though up to 5 minutes or so.
Also, an impact like that would be written in the geological record with a mass extinction 10 to 15 million years before the KT one....and there is no record of that.