Re: Diplodocus: Return to the Swamps????

[David Marjanovic <david.marjanovic@gmx.at>]

Post by Anthony Docimo rescued from truncation, containing quotes from 
don ohmes:

>  > Obviously=2C hippos will be extinct soon.
>
>  hippos can chomp right through a croc=2C thus providing disincentive 
to at=
> tack hippos.

Adult hippos are too round to be bitten by crocs. I'm not kidding.

Babies are at risk, except they're being defended by the adults like... 
this:
http://scienceblogs.com/tetrapodzoology/2009/11/hippos_killing_crocodile.php

The most hippo-like sauropods -- those with the widest and therefore 
roundest bodies -- are the titanosaurs, which have been associated with 
dry upland regions in at least one recent study.

> (and their legs *are* pillars=2C true=3B but they're also incredably 
short =
> - unlike the sauropods I've heard of.

True.

> (hippos use their legs more to punt themselves through the water=2C 
more th=
> an walking)

Well, they walk at the bottoms of bodies of water (they're much denser 
than any sauropod, so they can), and they walk around at night when they 
come on land to graze.

Interestingly, despite being digitigrade, hippos are incapable of running.

>  > The image of a lone mud-constrained giant covered by ant-like swarms
>  > of k=
> > nife-toothed croc-types isn't likely a realistic scenario in a 
swamp. Crocs=
> > are ambush predators=2C=20
>
> at least the modern crocs are.

That's not the question. The important part is that crocodiles are 
capable of learning from the behavior of their prey... they're not too 
stupid to pass up a free meal.

>  > Assuming an adult sauropod is in mud so deep that the base of the
>  > neck at=
> > the water/mud surface=2C they would be quite vulnerable to croc 
attack=2C =
> > especially if the head was also at that level. In shallower 
situations=2C i=
> > t is the croc that is tactically vulnerable=2C mostly to 
stomping=2C especi=
> > al here groups* of sauropods are involved.=20
>
> if the mud is such that it traps the feet of carnivores=2C stomping 
may no=
> t be a very useful defense.

If the base of the neck is at the mud surface, the poor sauropod cannot 
move at any perceptible speed and is therefore a free lunch. :-|

>  > Also=2C a well-trodden bottom laced w/ the bones of over-bold
>  > predators a=
> > nd compacted vegetative material would offer the hind legs an 
excellent pla=
> > tform from which to launch a counter-attack w/ the relatively 
compact front=
> > feet.

If the forequarters can be pulled out of the mud quickly enough. That is 
to be doubted.

>  > Watching the familiar video of the gigantic croc(s) attacking the
>  > flanks =
> > of migrating wildebeests gives the impression that even w/ those 
relatively=
> > small herbivores=2C attack success is hardly guaranteed. Further=2C 
breaki=
> > ng a sauropod into bite-size chunks might prove to be somewhat 
troublesome=
> > =2C=20

If it can't move quickly enough, it's a free lunch.

Crown-group crocodiles, *Deinosuchus* included, have conical teeth as 
incapable of cutting as a wolf's canines. The goniopholidids are outside 
the crown group, and they have cutting edges on their teeth. They're 
known from the Early Jurassic through the Late Cretaceous, and I think 
the very end of the latter.