The Miocene Mystery

[JDaileyGreatLakes]

When looking up the Cenozoic Era, one might assume that as Antarctica gained ice during the Eocene, the climate began to cool down.

Evidently, not so for the Miocene Epoch. It experienced a short burst of warming after 20 million years of cooling. http://www.nature.com/ngeo/journal/v7/n ... o2119.html

That was when the most familiar, modern families and genera of birds (corvids, cassowaries, ducks, geese, swans, doves, pigeons, seriemas) and mammals (baleen whales, pantherine cats, belugas, sperm whales, capreolinid deer, beavers, procyonids, opossums, pandas, foxes, canines, felines, great apes) started to appear. Is there some kind of connection between the arrival of modern birds and mammals and this warming spell?

And if that warming never happened, if the post-Eocene average global surface temperature continued to slope downward uninterrupted before the Pleistocene, would we still have some of the modern families and genera of birds and mammals?

[20 characters!]

Eh, imagining the marking continuing is much more intresting.

[Prudentia]

Most likely, all of those groups would still exist, but with some differences (either minor or major).

[JDaileyGreatLakes]

Eh, imagining the marking continuing is much more intresting.

What do you mean?

[20 characters!]

Eh, imagining the marking continuing is much more intresting.

What do you mean?

Imagining the warming continuing would be more fun.

[JDaileyGreatLakes]

More fun how?

[20 characters!]

More fun how?

Humans, mammoths, moose and lots of other modern creatures don't evolve in the way that we know them, tropical forests take over the world apes diversify to a ludicrous level the killer Dolphins (https://en.m.wikipedia.org/wiki/Squalodon) would not die out but possibly become more extraordinary.

Terror birds, would not only not die but spread and diversify THROUGHT North America

I mean it's like you've never even thought of what "cancelling the ice ages" might do.

OOOH but it gets more extreme, those Great Lakes your so fond of....gone, they only existed because of glacial action.

A greenhouse event 5 million years ago, if sustained could lead to a fairly diffrent world, imagine tigers in Spain, possibly.

[Prudentia]

More fun how?

Humans, mammoths, moose and lots of other modern creatures don't evolve in the way that we know them, tropical forests take over the world apes diversify to a ludicrous level the killer Dolphins (https://en.m.wikipedia.org/wiki/Squalodon) would not die out but possibly become more extraordinary.

Terror birds, would not only not die but spread and diversify THROUGHT North America

I mean it's like you've never even thought of what "cancelling the ice ages" might do.

OOOH but it gets more extreme, those Great Lakes your so fond of....gone, they only existed because of glacial action.

A greenhouse event 5 million years ago, if sustained could lead to a fairly diffrent world, imagine tigers in Spain, possibly.

20 has a point. Since you just sped up the rate at which climate cooling occurred, and only went so far back, this current state would likely be the result, with some mid level modifications.

If you want something drastically different, change the condition that occurred from 55- about 30 million years. That would be more likely to result in a recognizable, yet drastically different biota.

[JDaileyGreatLakes]

[/quote] If you want something drastically different, change the condition that occurred from 55- about 30 million years. That would be more likely to result in a recognizable, yet drastically different biota.[/quote]


How, specifically, did you mean "drastically"? Because I already had an idea, just curious if it's an idea the both of us would share.

[Prudentia]

If you want something drastically different, change the condition that occurred from 55- about 30 million years. That would be more likely to result in a recognizable, yet drastically different biota.[/quote]


How, specifically, did you mean "drastically"? Because I already had an idea, just curious if it's an idea the both of us would share.[/quote]

Prevent placentals from colonizing North America, make the early years mammals be dominated by something not hot and wet. Change when the plates broke up, Or focus on one area and do something to that area.

There are dozens of possibilities, hell, you could even go back and stop the Permian extinction. That is the only thing that allowed the crocodilians and archosaurs to displace synapsids, which were quite dominant before the Permian Exticntion Event.
Since every group has formed under unique circumstances, you could easily create conditions that would not have allowed for that group to form, or would drastically change them.

In the time period you working in, 20 million years ago (give or take), changing anything there does not give enough time for evolution to fill in the blanks, except with a few exceptions. Bats took 15 million years to go from aboreal to fully arial. So to actually come up with anything viable you really should move your time line back more. Especially since most of our modern stuff had already by 20 million. The direct ancestors and condition for their (dispuatably) inevitable formation were in place at least 30 million years ago, if not longer.