…"This new study makes a first attempt to calculate in more detail the implications of this idea. It suggests that it may have been to the advantage of young sauropods trying to get enough nitrogen to have a metabolism rather like modern mammals, but that this would have been impossible for the adults because of the danger of such large animals overheating from all the heat that such a metabolism would have produced."
Talk about simple. Nitrogen does provide energy for mammals. It’s the currency of energy, in many ways. However, that’s not much of an argument.
The big sauropods ate conifers from tall trees. There were no grasses, only conifers, ferns, and some more primitive types of plant. These super tough plants are anything but chemically simple. Nitrogen, yes, and plenty of it, but that’s hardly the whole story. The average pine nut, for example, is gourmet survivalist food because of its chemistry and nutrient values.
A bit of analysis:
• Plants contain:
• Mineral trace elements
This is a pretty good selection of building blocks for any organism. The giant sauropods consumed tons of these materials. They also consumed large amounts relative to body size. Add tons of growth medium materials to an organism, and it’s going to grow. Big.
• The sauropods were basically gigantic walking compost ovens in terms of contents.
• All organisms must
have thermal management systems.
• The extra heat may well have provided useful warmth for managing their circulation. That heat had to be distributed, and there was plenty of sauropod cubic space to distribute it.
• Better circulation, gigantic amounts of organic materials, you get gigantic sauropods.
Add to this the known growth spurts in dinosaurs overall. They grew big fast. Size was an asset to these creatures. The big sauropods were like elephants, far too big by far for individual predators. They could practically tread on single predators.
Getting big fast also meant they could access their food faster. The machinery of growth had to support these processes. The most likely answer is that their huge intake of plant materials provided a lot more than energy. It provided the framework for the big skeletons, the huge organs and nervous systems.
These animals also lived in a higher oxygen mix atmosphere. Highly oxygenated blood could support these giants.
We’re dealing with a totally different type of biology, adapted to a different world. Let’s not assume that what holds good for later species applies to the big sauropods.