# Aquatic dinosaurs? **URL:** \ **Category:** Factual Questions\ **Created:** [April 24, 2017, 4:12pm UTC](https://boards.straightdope.com/t/aquatic-dinosaurs/785150 "2017-04-24T16:12:03Z")\ **Posts on this page:** 6\ **Page:** 2
**Author:** ![Sailboat](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/sailboat/32/461_2.png) [@Sailboat](https://boards.straightdope.com/u/Sailboat)\ **Post date:** [April 25, 2017, 5:10pm UTC](https://boards.straightdope.com/t/aquatic-dinosaurs/785150/21 "2017-04-25T17:10:40Z")
> [@Colibri](#): > > It is generally believed today that sauropods were primarily terrestrial, based on various lines of evidence including anatomy and probable diet. Some did, however, live in wet environments such as river margins or near marshes. (Of course, these are the environments in which fossils are most likely to be created as well.) Yeah, some wading is possible, but one of the more persuasive arguments against the old vision of sauropods submerging their whole bodies in water to “support their weight” is the realization that, once the animal is submerged and using his long neck to keep his head above water, the water pressure that deep would make it impossible to inflate the lungs and breathe. Sauropods, [despite recent research suggesting they are more distantly related to birds than previously believed](https://www.nytimes.com/2017/03/22/science/dinosaur-family-tree.html?_r=0), do have a lot of hollow bones, and probably had the same sort of highly-efficient respiration and cooling system birds have. But that still wouldn’t help them overcome water pressure. It seems unlikely they would have lived in water like crocodiles. ---
**Author:** ![Colibri](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/colibri/32/1841_2.png) [@Colibri](https://boards.straightdope.com/u/Colibri)\ **Post date:** [April 25, 2017, 5:22pm UTC](https://boards.straightdope.com/t/aquatic-dinosaurs/785150/22 "2017-04-25T17:22:46Z")
The fact that they had air sacs and hollow bones means they may have been too buoyant to submerge at all. And the hollow bones strongly argue against them being aquatic to any extent, since most aquatic animals have dense bones to help them submerge. ---
**Author:** ![Gunslinger](https://avatars.discourse-cdn.com/v4/letter/g/4491bb/32.png) [@Gunslinger](https://boards.straightdope.com/u/Gunslinger)\ **Post date:** [April 25, 2017, 8:31pm UTC](https://boards.straightdope.com/t/aquatic-dinosaurs/785150/23 "2017-04-25T20:31:01Z")
> [@carnivorousplant](#): > > Swam or waded? > Although I have seen video of elephants swimming. Sauropods (Brachiosaurus, Diplodocus, and their ilk – the giant long-necked ones) had extensively pneumatic skeletons. If anything, they wouldn’t be able to _not_ swim in water over a certain depth. Y’know, just like [that other large long-necked dinosaur](http://i.imgur.com/hUIpsp9.jpg). ---
**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\ **Post date:** [April 25, 2017, 9:05pm UTC](https://boards.straightdope.com/t/aquatic-dinosaurs/785150/24 "2017-04-25T21:05:54Z")
Well, floating on top of the water would mean they wouldn’t have a problem with breathing against the pressure, and it’d still support at least part of their weight (though the bottom of the torso would still need to support the top of the torso). ---
**Author:** ![carnivorousplant](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/carnivorousplant/32/3563_2.png) [@carnivorousplant](https://boards.straightdope.com/u/carnivorousplant)\ **Post date:** [April 26, 2017, 1:34am UTC](https://boards.straightdope.com/t/aquatic-dinosaurs/785150/25 "2017-04-26T01:34:30Z")
> [@Chronos](#): > > Well, floating on top of the water would mean they wouldn’t have a problem with breathing against the pressure, and it’d still support at least part of their weight (though the bottom of the torso would still need to support the top of the torso). I would think they didn’t float very high. How high do whales or humans float? I recall that a human can breathe through a snorkel for three feet. Perhaps they floated with their lungs slightly underwater. I am still amazed seeing elephants paddle around with those flat elephant feet. ---
**Author:** ![Darth\_Ayebaw](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/darth_ayebaw/32/9870_2.png) [@Darth\_Ayebaw](https://boards.straightdope.com/u/Darth_Ayebaw)\ **Post date:** [May 18, 2017, 4:05am UTC](https://boards.straightdope.com/t/aquatic-dinosaurs/785150/26 "2017-05-18T04:05:20Z")
I asked this before as well - you might find this interesting: [Why no aquatic/flying dinosaurs? - Factual Questions - Straight Dope Message Board](http://boards.straightdope.com/sdmb/showthread.php?t=642978) [Previous page](https://boards.straightdope.com/t/aquatic-dinosaurs/785150.md?page=1)