Why no Australian Land Tortoises?

[chosen2030]

Just wondering if anyone can shed some light on the scientific reasons behind why land tortoises do not exist in Australia?

 

[Grandpa Turtle 144]

Because God didn't put any there !
And not enough grass in the dry season !


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[chosen2030]

Because God didn't put any there !
And not enough grass in the dry season !


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As dry as Africa's dry season can be, that still seems odd. Not all of Australia is dry, right? I can't imagine it can be since freshwater turtles exist there. Why no land tortoises in those areas? Just interesting that in a land rich in reptile life that land tortoises are non-existent.

 

[dmmj]

Aus. deep dark secret, they were eaten by the koalas. Blood thirsty monsters.

 

[wellington]

Haha. I don't know why, but maybe because there is already so many cool and adorable animals they just didn't need any more

 

[Tom]

I've wondered this myself. I don't have an answer for you. Let me know if you find one.

 

[Grandpa Turtle 144]

Cause torts don't have a spot for a pouch !


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[chosen2030]

These replies have hardly been scientific. Anyone have an explanation/insight based on zoology/herpetology?

 

[ascott]

http://www.wired.com/2010/08/last-giant-land-turtle/

You now have me curious....hmmm, I will share what I find

 

[ascott]

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

 

[Merlin M]

Could Australia have broken away before tortoises evolved? Just a guess

 

[ascott]

Could Australia have broken away before tortoises evolved? Just a guess

I am thinking this is the prime factor...still getting it together here....

 

[tyguy35]

It's just the same as why there are no vipers there. When the continent shifted the species did not inhabit that area of land. My best guess

 

[ascott]

http://www.explorebioedge.com/bio-bullets/item/47-the-puzzle-of-a-tortoiseless-australia.html

http://www.explorebioedge.com/bio-e...d-the-australian-tortoise-trump-the-hare.html

 

[shanu303]

i believe they did inhabit the land mass of Australia before separation but when geographic isolation of Australia took place and marsupials in Australia evolved the tortoises vanished same as the marsupials vanished from other continents as the other mammals evolved.... i believe the tortoises don't exist now in Australia same way as Australian marsupials aren't found anywhere in the other parts of the world... i believe it happened due to geographic isolation... that's what i studied in my school

 

[tortadise]

i believe they did inhabit the land mass of Australia before separation but when geographic isolation of Australia took place and marsupials in Australia evolved the tortoises vanished same as the marsupials vanished from other continents as the other mammals evolved.... i believe the tortoises don't exist now in Australia same way as Australian marsupials aren't found anywhere in the other parts of the world... i believe it happened due to geographic isolation... that's what i studied in my school

This is spot on. When Pangea was in place, Australia was actually below Antarctica. North of Australia was Tibet now. The faults more than likely at those points of movements blockaded the land moving reptile there. It was quite a rough area given it's position. It underwent extreme summers, and extreme winters. Thus the marsupial "pouch" animals. Adapted to protect their young better from extreme harsh environmental exposure.

I will ask my mom to come on and give a good response. She's got a masters in geography and geology and lev this stuff. She may have a good scientific response. Better than mine at least. Ha

 

[Moozillion]

Interesting thread!

 

[FLINTUS]

Kelly has summed it up nicely. Due to Australia's geographic position in Pangea, it had very extreme temperatures. It also was not easy to move to for the tortoises, as Kelly said again, there were a number of mountain ranges in that part of Pangea I believe.

 

[diamondbp]

It is an interesting question without a doubt. I've always wondered what the reason may be. I've also always wondered why there isn't any species of poisonous turtle/tortoise

 

[Star-of-India]

Now tortoises have colonized many islands, eg., the Galapagos, by floating, likely on debris, out to them. I'd guess the ocean currents between Australia and the mainland are not favorable for that sort of animal dispersal and of course why placental mammals only made it there with the help of humans.