New World Monkey origins
 

Hey all! I thought I'd relate to you folks something I was telling a few Cellarites in chat the other day.

Today, there are monkeys living in Africa, Asia, and South America. Species that were ancestral to monkeys, however, are NOT found in any of the fossil deposits in South America. This is because South America was an island continent for most of the Cenozoic era (65 million years ago to present). This means that at some point in time, monkeys, who had been evolving in Africa for quite some time, just magically appeared in South America.

In the Eocene (37 - 53 million years ago), which is about the time anthropologists think monkeys arrived in South America, the earth looked like this:

http://comp.uark.edu/~dmorton/images/misc/eocene.gif

This geography presents a problem to anthropologists. Since South America was an island when monkeys first appeared there, how in the bloody hell did they get there??

The current working theory is that they rafted there from Africa on floating masses of vegetation.

Apparentely, huge chunks of vegetation actually do break off now and then and just float away. I don't know much about this, except that I'm told it's been documented to happen, and still happens today.

If monkeys did raft to South America, they could have come from three places: North America, Africa, or Asia (through Antartica). Most anthropologists seem to think an African origin is most likely, based on the similarities of certain fossils. The ancient water currents would also have been favorable for an African origin.

They could have also traveled from North America via Island-hopping. Lots of people seem to also be for this origin, but it seems unlikely because A) rafts of vegetation don't form on small islands, and B) the species in North America that NWMs would have evolved from are much farther down the evolutionary tree than the potential African ancestors.

Another suggestion is that they came from Asia, rafted across to Antartica, and traveled via a land connection to South America. But since no primate ancestors have been discovered in Antartica, not many people are for this idea.

When I told Whit and Slang about this, Slang asked about travel times. That's answered in this paper, which has the following chart:

http://comp.uark.edu/~dmorton/images...m_origins1.gif

The linked PDF argues for an Antartic route, and it goes into much more depth about this stuff. So it's worth checking out if you're interested. Anyway, that's all I'll say on that for now. It's really fucked up, sounds compeletely ridiculous, and is only the current working theory because there are no other ideas.

edit:

According to the linked articlle, this theory is also used to explain to origins of South American acridian insects, West Indian Coleoptera, Lake Malawi fishes, many shallow-water animals, some amphibians and reptiles including Crocodilia, Crotalus rattlesnakes of Baja California, land reptiles of Western Samoa, South American indigenous gekkos, some land vertebrates of the Krakatau Islands, land mammals of the Mediterranean islands, South American caviomorph rodents, a group of Australian rodents, and possibly a group of South American sloths.

Interesting research juju. And to think is was a big deal when Gertrude Ederly swam the English Channel.

My own theory involves some monsterous tornado that picked up a breeding pair in Africa and deposited them in South America. Hey, could have happened.

"Toto, I don't think were in the Congo anymore..."

What about other little islands?

I don't see that in here anywhere... which one are you reading, King James?

What do you mean, UT?

Well, the canary islands are kinda in the zone there, and if the continents were in different locations they could provide a mid-point for a for a few tens of thousands of years until it could make the final leap.

or they could have been carried by african swallows......they could grip them by the husk!

Clearly they were brought over by the same aliens that later influenced the local architecture.

It all started when K'Thagon ran for office on a platform of "a monkey for every continent".

It's not a question of where he grips it! It's a simple question of weight ratios! A five ounce bird could not carry a ten pound New World Monkey!

Well, maybe a team of swallows could carry a monkey!
--

I had not realized that Europe had ever been a continent in it's own right! Damn. Now I might have to stop ranting about Europe not being a continent .. and start ranting about how it should be treated as a subcontinent, like India!

I also hadn't realized that Asia has been spinning!

That would have been wonderful geography, though. Excellent shipping lanes by sea.

Chicxulub seems quite evident in this picture, too.

That's possible.

According the linked article: "tropical large rivers and lakes with an access to the ocean are likely places of floating island growth, and these kinds of rivers and lakes are rarely found on small oceanic islands".

So, it seems unlikely (though, so does this whole scenario).

See that region of water in between Europe and Africa? That's called the Tethys Sea. When it closed up, that completely changed ocean currents, the climate of the entire world changed, and a ton of species were wiped out.

I'm trying to find more details on the net, but failing. Still, it's really cool how one seemingly insignificant geographic thing can change the entire world.

I'd like to point out that the paper has not *answered* Slang's question. It's an educated guess, at best. Besides, everyone knows that monkey eggs float like coconuts.:rolleyes:

BTW- Tethys Sea closing up is an "insignificant geological thing"?

Perhaps two swallows could have carried the monkeys with a string.

Nah, I just meant that it seems insignificant, but of course it isn't.