[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Subject Index][Author Index]

RE: Diplodocus: Return to the Swamps????






>>> You seem to miss the reality of
>>> a swamp; sooner or later you _sink in_ no matter how
>> 'spready' your feet are. At which point,
>>> 'spready' feet are a serious _disadvantage_. Swamps
>> often have sharp sticks, logs, even rocks
>>> that can function as impalers or entanglers. If the
>> area has a bottom you can reach, you WANT
>>> compact feet that slide easily to it, and then
>> _retract_ easily.
>>
>> Theropod feet spread on the way down, but fold up into a
>> nice compact narrow shape on the way
>> back up. The spread foot makes it more difficult to sink
>> into the mud to begin with (and less mass
>> doesn't hurt either). The more compact retracting shape of
>> the foot means it's easier to extract it
>> from the mud than it was to push it in.
>
> Spread toes are vulnerable to injury in deep mud when you weigh several tons. 
> "...sharp sticks, logs,..."
 
 yes, and imagine a compact foot stepping on a sharp stick and-or log.   (this 
is why elephant handlers in zoos and parks must always check their wards' 
footpads)
 
 
>>> And less power...
>>
>> Mass isn't necessarily a good measure of power. In fact,
>> I'd go as far to suggest that theropods
>> had a greater proportion of locamotive muscle mass than
>> sauropods had. A biped needs leg
>> muscles to actively keep it upright. A quadruped just has
>> to lock up its leg joints when its not
>> moving, and it turns into a passive table.
>
> That is relative power. Mice have very high relative power, but cannot break 
> free of a sticky trap... absolute power is what is needed in mud. Sauropods 
> had the mass AND the leverage.
 
 column-like legs, no toes, dozens of tons pressing down (and probably more 
than one leg stuck in the mud)...so what leverage do they have?  it's not like 
they can bite a tree and use their neck and-or tail to assist in pulling 
themselves out.
 
 
>>> ...When you are up to butt in mud, you have no
>> worries about that...
>>
>> I'm not envisaging regularly moving through crotch-deep
>> mud, since no sane animal would do that
>> very often.
>
> Nothing insane about being theropod-free when you have a long skinny neck and 
> tons of tasty meat. Not to mention being thermally stable.
 
 its been a while since I checked - does mud insulate or suck heat out?
 
> Takes the weight off achy feet, too. Reach up, nip a few leaves, go back to 
> sleep...
>
> Big old mud-bug could have a good life.
 
...until the crocs ate the mud-bug.
 
                                          
_________________________________________________________________
Hotmail: Powerful Free email with security by Microsoft.
http://clk.atdmt.com/GBL/go/171222986/direct/01/