Why Were Prehistoric Bugs So Huge?
For the longest time experts assumed bugs that lived millions of years ago became extremely large on account of the fact that there was nearly twice as much oxygen in the air as today. This theory makes sense, since more oxygen would mean larger volume of internal caverns located in the tissue of prehistoric organisms. In other words: more oxygen=greater body size. However, experts now believe prehistoric bug larva was also a factor in making prehistoric animals enormous.
To test the theory scientists focused on the Stonefly Larvae. Much like the insects that are known to have been huge between 299 and 360 million years ago, such as dragonflies, Stonefly Larvae lived in water before becoming adults. And higher oxygen levels means more oxygen was dissolved in water, which could explain how insect babies that dwelled in water became gigantic before reaching adulthood.
This theory seems more likely than adults becoming large due to higher levels of oxygen in the air because Stonefly larvae are more sensitive to higher oxygen levels in water as opposed to adults living on land. Whatever the case may be, lets just be thankful oxygen levels have dropped!
Can you imagine living with insects that are so large? Do you think humans would be at the top of the food chain if they were?