Megafauna, Why Were they Mega and not Smaller?

This has been an unsolved mystery. Why were the dinosaurs so tremendous, far gianter than any land fauna since. Why are the whales the largest living in time? Why were the icea ge megafauna somewhat large but not so as the dinosaurs? Why were there great dinosaurs yet no giant cold blooded whales in the Mesozoic?

The answer seems to be, the amount of territory available to the fauna and the amount of food in this realm, what makes food available is good weather! The dinosaurs and the whales have one thing in common, good weather for them. The land was unified in the time of the dinos and the weather was good. The earth was spinning faster so the dinosaurs if cold blooded as I believe they were would have had neither too much overheating in the daytime and more important, no shock of PM cooldown as reptiles have now. The sun was in an interglacial age for much longer so it may have been burning hotter. The dinosaurs wouldn't have been warm blooded because they wouldn't have needed or wanted to overheat. They were far too great to have been able to function in the heat, even if more constant. The warmer generally constant temperatures would have been good for endothermic life. Even so the earth is slowing down because to the tides and reptiles today are much smaller even if they live in the tropics because of the nightime stress of the cool, it's often below freezing at night in the desert.

So too, too much constant temperature may have been the limit to the size of the earlier cold blooded fish in the time of the dinosaurs. If the fish arose sooner in evolution, they might have been larger even before the dinosaurs. Life thrives on not change or the lack of change. It thrives on optimi-zing, when the whale zings! This is why science shows living in the suburbs is healthier than the city or the country or why the bourgeois are healthier than rich and the poor, same hour, life is real! For a cold blooded fish in more constant warmer waters like in the mesozoic life they would have improved if more optimum change was there, the lack of change of temperature like now may have limited their size the. Later the whales being warm blooded had the more extreme temperatures each AM and PM above the surface enough to create the better levels of temperature that helped them thrive. Like the dinosaurs they had a vast realm to explore and search for a vast amount of healthy food, even more than they. Business tends to become giant only if there is a large stable economic base, in history the cities North of the alps in Europe were smaller and not so old while the cities in the South were large and of enormous antiquity, for much the same reason, whales and dinosaurs were giant because of the giant stable temperatures in their domain over great ages of time.

The whales were even larger than the dinosaurs because they have an advantage of buoyancy, even today, shipping by water is by far the cheapest per pound shipped, land sea or air.

That the dinosaurs were endotherms would also fit my picture of how they went extinct and the rise the birds and mammals; the land bridge submerged about 87 million years before the cretaceous dinosaur impactor between Patagonia and Antarctica; the land bridge would have made the S with a continuous belt of water different from the land of the N and this would have caused torque and the tilting of the earth (seasons). The dinosaurs if endotherms, would be in an ever nearer zone of the tropics, and the comet would have caused their demise, essentially just by luck. Some say they were showing "signs of old age" in their evolution, but species like corporations in business are theoretically immortal. The stress seen would be because of the worsening weather. If the dinosaurs were killed just by luck, it seems more possible they could have one day evolved to higher levels of intelligence. Some dinosaurs had both hands almost like more evolved life, large brains, and upright locomotion. The birds and mammals being warm blooded went N and S with the new weather, occupying the large areas left by the dinosaurs, so they were saved from the comet, ect.

The smaller large power base would explain why the ice age fauna were giant but not so giant as the dinosaurs. The megafauna had a great source of nourishment from the glacial lakes that dug up the soil by the glaciers so a large supply of healthy nutrition was in reach. Since the climate was cool, they weren't inclined to overheat and if it was cool at night they were warm by being warm blooded. The reason they were not more giant yet was because of the limits of the food power base, after the breakup of the more unified dinosaur continent the East and West hemispheres were a smaller food and power base for the ice age megafauna than the dinosaurs or whales. It's been estimated at any one time there were just 6 T Rexes in N America, even as giant as they were, there were no more or less because they were integrally based on the land, no more land no more size beyond a certain level. More good land more size no doubt, but there was a limit even here.

You may have read of perusaurus, the giant alligator like reptile that was even more giant than the dinosaurs. This behemoth lived in Peru about 37 million years ago long after the dinosaurs, one you may not have heard of because Perusaurus wasn't a major trend in evolution like the dinosaurs. Giant size evolution has thought of often, in truth we are larger than the ancients like in Pompeii. Unlike the dinosaurs Perusaurus had only the small power base of the amazon basin so like the Maya civilization compared to Eurasian civilizations which historians think got the advantage in history and colonization because of a larger power base of good weather East to West with other land with a N to S weather pattern. Historians believe history was like this because all the advantages like in science were conferred to all involved in the weather band, so the W built up power like naval power or the compass to colonize the New world. Thus perusaurus even if great for some time, even more than the dinosaurs wasn't able to maintain its power base if fickle since "smaller businesses" are often more prone to failure than a giant business, like the dinosaurs.

It's believed by others that bees and other insects have been limited in their evolution by the breathing tubes they use from the outside of their skeleton to their inner respiration. Supposedly the physics of the air are a limit to the available oxygen insects can use and this would limit their evolution to giant size. That there were giant bees and other related life in the Paleozoic seems to need better explanation, so my belief is that the other limit of the common diurnal 24 hour temperature stress is a major cause of the limit of the size of bees. This may be proven or disproved by experiments with large bees and better "indoor weather" over generations. If the bees are larger than than the physics of the air might allow, the temperature here too may have been one of the main influences on size in evolution.
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