alt Hacker NewsI don't know how convinced I am. First there were dinosaurs in the past, the brachiosaurus was 4 x as big as an elephant and there are probably yet undiscovered dinosaurs that were even bigger given discovery of partial fossils like the Sauroposeidon.
Also we know in the past there were dargonflys with wingspans greater than 2 feet and centipedes that grew as long as a car.
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Giant bugs are a totally different design though - don't they basically have a big exoskeleton made of different stuff than bone ? That's more like how we design a modern tank or airplane
It's also possible that for larger creatures a less dense and more flexible skeleton material (in general) might be ideal. Especially for animals that are not warm blooded (larger volume to mass ratio might resist temperature changes better?)
One theory about large sauropods is that they were aquatic animals that propelled themselves like hippopotamuses, using their feet against the bed of the lake/river. Just as whales can get very large, so could buoyant sauropods.
The atmosphere is believed to be more oxygen rich back then, in order for those dragonflies to exist.
Giant sauropods are basically big balloons, so that's a nice little hack around the issue. https://www.youtube.com/watch?v=WuMHfWSyoGI
They were larger but not as dense as mammals, we know had adaptations like less denser bones and different respiratory systems that allow for more efficiency and much more rapid growth into maturity. Modern birds show evidence of all these traits. When the Chicxulub extinction event happened it reset things so mammals got the upper hand on large sizes and eventully won out for the most part. Highly recommend The Rise and Fall of Dinosaurs, which I thought was going to be mostly stuff we learned as kids but was educational for me.