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Sufferin' Sauropods!

It's rather about time people came 'round to the idea of sauropods
being semi-aquatic, if not fully so. The counter-intuitive concept of
sauropods being solely dry-land dwellers has gone on way too long.  If
only we can also begin to dispel the absurd spindly-legs imagery of
them...
It's almost as if some people sit around dreaming up the least logical
behaviours (and other aspects) for dinosaurs, then take them on board
and promulgate them. The scavenger T. rex being another case in point.

Peter Markmann

On Monday, October 27, 2003, at 07:24 PM, Michael Habib wrote:
Careful; you're reading too much into this study. Those two papers
demonstrate that sauropods crossing shallow water for short distances could
create the rare forefeet-only prints. It does not imply that they were
semi-aquatic.

But it does dispel the contention that they couldn't dwell in a body of water at all. And it can't have been that shallow if the hind legs were floating or in use to propel the animal.

 In fact, the same authors also found that they were prone to
tipping in water, so sauropods would have had trouble in deep water.

I do agree that they wouldn't have fully submersed themselves; rather, they would have kept to depths that were sufficient to give them some buoyancy.

And what about the danger inherent to them tipping on land - as a result of high winds, stumbling or attack? This is a very serious consideration, given the way sauropods are currently depicted; they'd go crashing sideways to the ground if they were so much as a few inches off balance.

There is a host of evidence to show that sauropods were terrestrial. It has
been discussed here before, I believe, so I would refer to the archives for
an extended explanation and list of references. However, in short, it is
known beyond most reasonable doubts that they were terrestrial because of
limb morphology (columner limbs are a terrestrial adaptation and very poor
for swimming)

Indeed, but I'm not saying they swam, merely waded or wallowed. Nevertheless, elephants swim well with columnar legs. Are hippo legs too short to be considered columnar?

trackways (most were made on land), axial elements (they were
built like suspension bridges, very cool), and perhaps most
importantly...they lived in dry habitats. Wet/dry seasonal conifer forests
do not make for good aquatic living. 

I see conifers today besides lakes and rivers.

It's actually not that counter-intuitive. Large animals with straight limbs
tend to live on land. Giant tortoises (columner foot), elephants,
Indricotheres, etc. are all examples.

--Mike Habib

Again, hippos and elephants (especially the Asian varieties). Indian Rhinos, as well as the Sumatran & Javan (if there are any left). Tapirs and capybaras. Giant tortoises are the exception among their kind. Indricotheres may well have indulged in a semi-aquatic existence if the conditions were there. The proclivity of water buffaloes is self-explanatory. And seacows, whales and seals are large-to-huge mammals that enjoyed the aquatic life so much, they moved in permanently (as to how columnar the legs of their ancestors were, I couldn't say for sure).

Peter Markmann
Canberra