No Ice age

WI for some reason they had been no Ice age and that the climat of the Earth had stayed the same as when that period started
 
No one coming to America via the "land bridge" for one, and prehistoric hunters not hunting the large, prehistoric animals to extinction. This leads to a smaller, later colonization of America by man. And when they get there, big animals that (perhaps?) smarter and more agro-centered man will not hunt them into extinction. Wooly Mammoth ranch, anyone?
 
It would mean that the natural hot/cold cycles of climate had been suspended by an "alien" force able to stableize a planet's climate and to maintain that climate over a long period of time.
 
It would mean that the natural hot/cold cycles of climate had been suspended by an "alien" force able to stableize a planet's climate and to maintain that climate over a long period of time.

Actually the entire last cycle of ice ages would have been avoided if the Panama Isthmus had never appeared. Quite unlikely, seeing it is a result of the constant collision between the North and South American tectonic plates with the Pacific one though not entirely impossible... that collision was ongoing for moe than 100 million years and only formed a land bridge merely 3 million years ago...

The effects on evolution and wildlife would have been enormous. For instance, Southern Europe and the North American Great Plains would have been more or less tropical (sabana/steppe) and Central Africa entirely covered by different types of forests. South America would have remained a continent-island with its exclusive kinds of mammalian fauna like Australia is today. And the distribution of animals and their looks would be entirely different today... imagine horses and dogs as North American endemisms, for example. Plus, without the clearing of the Eastern African forests and the decreasing in fruits during the year it is quite possible that hominids would have not adapted to eat carrion and travel long distances while searching for it, and as a result "we" would still be merely bipedal chimpanzees, with an Afro-Eurasian distribution at best.
 
WI for some reason they had been no Ice age and that the climat of the Earth had stayed the same as when that period started

Which ice age? The last glaciation? Or the overall ice age, with all of it's glaciation periods? In the case of the latter, humanity may be butterflied away. In the case of the former, many human ethnic groups would be butterflied away, including the native Americans.
 
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