Atlantean Prehistory

[Ephraim Ben Raphael]

Although I felt that Turtledove's Atlantis series had a few to many butterflies, the idea of creating 'Atlantis' by breaking off the coast of North America is a good one IMO.

So what would be the geologic and evolutionary histories, of Atlantis if it existed?

[Ephraim Ben Raphael]

I suppose I'm the only person who is interested in somehting like this.

Was it something I said?

[Talwar]

I'm unfamiliar with the series, but if you were to scrounge up a map, I could speculate.

[gladiator8085]

What got me about the fauna of Atlantis was that apparently other than the alligators or crocs in the southern part there were very few predators.

[benjamin]

I've been thinking of doing an ISOT wherein Turtledove's Atlantis is transported to OTL. Both regions are in the year 1758 or there about. After the initial tidal waves and earthquakes things get back to normal.

Anyway - As for the natural history of Atlantis, I think Turtldove puts too little thought into it (as he's been doing for most of his recent work.) Atlantis would form as a separate mini-continent sometime in the late Jurassic as the Gondwanaland broke apart and formed the Atlantic ocean. This would be about 140 million years ago. Thus, initially Atlantis would share an ecology with the rest of the old super continent untl the K-T event put paid to the Dinosaurs (~65 million years ago). This would make Atlantis a relatively clean slate to be colonized by birds, bats and aquatic animals.

This opens Atlantis up for some interesting animals besides birds. New Zealand is far more isolated then Atlantis would be. Atlantis would have both crocodiles and pinnipeds which in turn could result in Atlantis having far more large animals and more variety. Also Atlantis is a much larger land mass so there are more resources available for the native ecosystem.

If memory serves me HT did mention a few animals besides the honkers, red-headed eagle and oil thrushes. These including very large snakes, gliding frogs and large croc animals that the natives called "dragons" but I would have to look this up to be sure.

Personally, I think the maps on the cover of the books are worthless and I generally use the attached map as a reference instead.

[Emperor Norton I]

This is actually a good topic, but I think the name may throw people off a bit. I'd suggest changing it to something like "Turtledove Atlantean Prehistory".

[Ephraim Ben Raphael]

Originally Posted by Talwar

I'm unfamiliar with the series, but if you were to scrounge up a map, I could speculate.

I have a rather rough Map.

Originally Posted by gladiator8085

What got me about the fauna of Atlantis was that apparently other than the alligators or crocs in the southern part there were very few predators.

I think it was that Atlantis was populated by birds like New Zealand was, so the top predator is a really big eagle, a-la Haast's Eagle.

Originally Posted by benjamin

This opens Atlantis up for some interesting animals besides birds. New Zealand is far more isolated then Atlantis would be. Atlantis would have both crocodiles and pinnipeds which in turn could result in Atlantis having far more large animals and more variety. Also Atlantis is a much larger land mass so there are more resources available for the native ecosystem.

If memory serves me HT did mention a few animals besides the honkers, red-headed eagle and oil thrushes. These including very large snakes, gliding frogs and large croc animals that the natives called "dragons" but I would have to look this up to be sure.

Personally, I think the maps on the cover of the books are worthless and I generally use the attached map as a reference instead.

So what kind of animals do you think would have evolved in Atlantis that Turtledove missed? He mentioned crocodiles, I think in the book. I didn't know that a map came with Audobon in Atlantis by the way.

[benjamin]

Well, first off given Atlantis' location there will almost certainly be seals and sea lions on Atlantis. With a large relatively empty land mass it is easy to see these pinnipedes evolving to fill numerous roles from large grazers similar to OTL elephants, which are related to pinnipedes in real life, to sleek predators akin to land based leopard seals. Crocs on the other hand were once far more diverse than they are today, and on Atlantis with fewer mammals to contend with they are likely to become far more varied. Picture small predatory crocs filling the role of weasels and large land based predators behaving in a manner akin to bears.

The possibilities are endless given that evolution is given a big ecological blank slate to work with.

Benjamin

[Dave Howery]

I don't think HT was that far off in his depiction of what Atlantean wildlife would be like... considering that Atlantis is about in the same role as New Zealand was. Both were fairly large landmasses that are pretty isolated, and have been for a long time. It stands to reason that since mammals didn't find their way to Atlantis that birds might follow a similar path, becoming large flightless browsers and grazers (having geese be their ancestors was a neat twist). Pinnipeds and crocodiles never really took to the land in NZ, and it doesn't seem likely they'd do so in Atlantis. One interesting point not covered in the books: you have to wonder just what the people would think after NZ is discovered and it's realized that that land mass had nearly identical wildlife to Atlantis... maybe spur the idea of evolution a little faster?

[benjamin]

Dave - While HT may have wanted Atlantis to be ecologically similar to New Zealand that doesn't mean it would be that similar. First of all Atlantis is far larger than NZ. This would give colonizing species far more resources to utilize and more ecological niches to fill, which will promote more varied evolution. Second of all Atlantis is less isolated than NZ which gives more species the chance to reach the land mass.

Once again HT just wanted a recognizable parallel that readers could identify with, and given how he churns out books and gives very little background information on his alternative histories; I would also assert that he is overstretched as a writer and a bit lazy when it comes to research.

Though I do agree that Atlantis may give evolutionary theory an early boost as the settlers recognize similarities between the animals on Terra Nova and Atlantis.

Benjamin

[Dave Howery]

Originally Posted by benjamin

Dave - While HT may have wanted Atlantis to be ecologically similar to New Zealand that doesn't mean it would be that similar. First of all Atlantis is far larger than NZ. This would give colonizing species far more resources to utilize and more ecological niches to fill, which will promote more varied evolution. Second of all Atlantis is less isolated than NZ which gives more species the chance to reach the land mass.

Once again HT just wanted a recognizable parallel that readers could identify with, and given how he churns out books and gives very little background information on his alternative histories; I would also assert that he is overstretched as a writer and a bit lazy when it comes to research.

Though I do agree that Atlantis may give evolutionary theory an early boost as the settlers recognize similarities between the animals on Terra Nova and Atlantis.

Benjamin

But it's still a question of 'what can get there?' Apparently, Atlantis has been isolated from the rest of the continents since before the rise of mammals, since there aren't any there other than bats and pinnipeds. Reptiles, amphibians, and insects are natives, birds could get there, but not much else. Atlantis isn't as isolated as NZ, but it's still isolated... land mammals don't have a way to reach it. Giant flightless birds are a very logical end result, since they did arise in several other isolated places... heck, they even had them on Madagascar, which did have mammals. Giant flightless geese are a neat twist on the idea...

[benjamin]

Originally Posted by Dave Howery

But it's still a question of 'what can get there?' Apparently, Atlantis has been isolated from the rest of the continents since before the rise of mammals, since there aren't any there other than bats and pinnipeds. Reptiles, amphibians, and insects are natives, birds could get there, but not much else. Atlantis isn't as isolated as NZ, but it's still isolated... land mammals don't have a way to reach it. Giant flightless birds are a very logical end result, since they did arise in several other isolated places... heck, they even had them on Madagascar, which did have mammals. Giant flightless geese are a neat twist on the idea...

I'm not arguing that large flightless birds won't exist on Atlantis, but I am saying that using New Zealand as a point of reference is flawed. Again Atlantis is massively larger. This allows for far more diversity. Something will evolve to make use of these habitats and the few animals mentioned by HT are just the tip of the ecological niches to be filled iceberg.

The ancestors of mammals were around by the time Atlantis was formed since it almost had to form in the Jurassic period as the Atlantic Ocean formed. Some of these would have survived the K-T event and gone on to populate Atlantis. Case in point is the Castorocauda which although from Asia is indicative of how advanced mammals already were despite competition from dinosaurs.

Also, why aren't there large ground based predatory birds similar to those that evolved in South America?

Benjamin

[Dave Howery]

Originally Posted by benjamin

I'm not arguing that large flightless birds won't exist on Atlantis, but I am saying that using New Zealand as a point of reference is flawed. Again Atlantis is massively larger. This allows for far more diversity. Something will evolve to make use of these habitats and the few animals mentioned by HT are just the tip of the ecological niches to be filled iceberg.

The ancestors of mammals were around by the time Atlantis was formed since it almost had to form in the Jurassic period as the Atlantic Ocean formed. Some of these would have survived the K-T event and gone on to populate Atlantis. Case in point is the Castorocauda which although from Asia is indicative of how advanced mammals already were despite competition from dinosaurs.

Also, why aren't there large ground based predatory birds similar to those that evolved in South America?

Benjamin

true, I'm kinda wondering just how Atlantis managed to stay isolated from the other continents for such a long time so that mammals never made it there... I'm just going by the books here. But if we take the basic idea that there aren't any mammals there (again, just going by the books, regardless of how logical it is), then it's understandable why there aren't any giant carnivore birds... what would they eat? They can't really exist on lizards and snakes. Big grazing/browsing flightless birds are much more likely. There are probably smaller reptile hunting birds (along the lines of roadrunners and shrikes)... and of course, the giant eagle. Although the idea of Atlantis not having any mammals doesn't really make sense, if we assume that, then HT's ideas are pretty reasonable...

[benjamin]

Agreed. if there are no mammals then HT's ecology makes sense. And since it's HT's world he can do as he pleases, but...

That being said and all. I can't just leave it at that (which is why I like alternative history so much).

There is a very good chance that Atlantis had a full and varied ecology up until the K-T event. That being said the K-T event destroyed that ecology, but there is no reason to believe that there were no mammalian survivors on Atlantis. Our own history shows that it took a while but within a few 100,000 years the forests and plants had fully recovered. At first populated by small mammals and reptiles as well as birds, some of which were becoming the large predatory types, after about 10 million years the mammals began to diversify and fill many of the open niches. I would contend that the same would happen on Atlantis as well despite its isolation.

Here's a picture of gastornis, one of the first large predatory birds to arise following the demise of the dinosaur. Being native to North America and Europe it easy to see something like this appearing on Atlantis.

Benjamin

[benjamin]

And here is a map I did of Atlantis. It doesn't match HT's Atlantis exactly, but I wanted to vary it a bit for an ISOT I am working on.

Ignore the political divisions.

Benjamin

[Dave Howery]

I suppose the key question is just when Atlantis became so isolated... if it was very early in the age of mammals, then Atlantis is likely to have a collection of bizarre animals... monotremes and marsupials, perhaps, like Australia. Since Atlantis isn't so dry and resource-poor as Australia, the mammals there might be bigger and a lot different; I don't know if you can say just how they would develop...

[DValdron]

As far as I can recall, both placental and marsupial mammals evolved in roughly the same time frame, approximately 130 to 136 million years ago in central asia, roughly china. As I understand their vector of transmission, they moved out from there into Europe and North America, from North America into South America, Antarctica and finally Australia. Essentially, spreading through the northern continent and then to the southern continent.

Turtledove's Atlantean territory would be right on this highway, so depending on the split, the Atlantean minicontinent could have had a viable collection of mammals at the time of the KT event.

But let's take another look at the geography here. What's interesting about Atlantis is that it is a tall minicontinent, but not a broad one. Taking a leaf from Jared Diamond, it strikes me that Atlantis would likely be a species diverse place.

Basically, stretching across a series of latitudes, it would tend to have a slightly different ratio of seasons and seasonal conditions all the way up and down. This would tend to encourage niche specialization.
Note that Atlantis is fairly narrow, so your miniclimates would be different on the east and west side as well, depending on ocean currents and wind and rain conditions.

Given a variety of distinct miniclimates, I would expect Atlantis to tend towards biological diversity, lots and lots of varieties of critter and plant. Which would probably make for pretty rapid evolution. Atlantis is a laboratory to promote rapid speciation.

On the other hand, Atlantis probably won't produce major megafauna. Not a big enough chunk of continuous habitat to produce megafauna. The best you'd get would be some land migrators, but I doubt it. While you'd have enough latitudes to specialize your climate, there wouldn't be enough meteorlogical space for them.

Let's see - Dinosaurs? No luck. I can't construct a plausible theory for the dinosaurs having Atlantis as a refuge.

Well, possibly. If Atlantean dinos evolved a wide diversity of small bodied forms, just maybe. But unlikely.

A mammal resurgence would be more likely. Not necessarily marsupials though, they seem to do better in more extreme and marginal environments. Believe it or not, Placental mammals colonized Australia at the same time as or earlier than Marsupials did. The Marsupials simply won the battle. They could handle the arid, biologically impoverished conditions better.

Atlantis, more likely a Placental homeland. But we could expect the local placentals to diversify into their own lineages. So no Canids, Felids, Ursines or Mustelids.

But probably something carnivorous. Marsupial Carnivores? Possibly. Big Bird Carnivores? Also possible. Also, resurgent crocodilian lines, including land crocs. Basically, the dog eat dog lifestyle seems to be open to all comers.

Herbivores? Likely complete domination by Placentals. I'm thinking predominantly forest as opposed to plains species. Browsers rather than grazers. Dear or Moose analogues. Possible Rodent analogues. Edentates?

With a bit of inspiration and enthusiasm, you could come up with some neat stuff.

Maybe even an intelligent species.

[DValdron]

One thing with Atlantis, its likely to miss out on the ice ages.

I think that most of it is just too far south for significant glaciation.

[Dave Howery]

so how far back would you have to go to get Atlantis isolated so much that there are no mammals at all, as in HT's books?

[benjamin]

Given that the Atlantic Ocean didn't really get formed until sometime in the late Jurassic to early Cretaceous periods ~ 140 to 120 million years ago I don't see how there cannot be at least proto-mammals on Atlantis. These early Atlantean mammals may take a different evolutionary path then the mammals we know and love, but they will still be there to compete with birds and reptiles.

Unless, of course we suspend all disbelief and say that this Atlantis was formed in a manner similar to the now gone mini-continent of the Kerguelen Plateau.

http://en.wikipedia.org/wiki/Kerguelen_Plateau

Benjamin