Hello,BK,I am very glad to ask you a question and my question about temperament of dinosaurs. I am interested most of all in the temperament of sauropods. What do you think,such dinosaurs as diplodocus,brachiosaurus or amphicoelias were calm and harmless creatures or not? Were they as aggressive as elephants and rhinos or were quite harmless as a giraffe? Also I am interested in the temperament of such herbivores as ankylosaurus and stegosaurus. Despite being well protected from predators, were they aggressive or not? Also what dinosaurs were more kind and harmless, sauropods or dinosaurs like stegosaurus and ankylosaurus;and also between sauropods like diplodocus or sauropods like brachiosaurus? And also what do you think, were sauropods good parents and could successfully protect their babies?
Thank you BK,
The exact temperament of dinosaurs is difficult to assess accurately. Any animal, including plant-eating dinosaurs, is capable of aggression if faced with the right situation. Even the peaceful giraffe can become dangerous when attacked by lions (and giraffes can kill lions with their kicks). Sauropods were most likely calm, peaceful creatures much like the giraffe is today, but would use whatever means possible to repel or escape from an attacking theropod (great weight to crush/tail to strike with/entry into a body of water). I wouldn't put them on par with most elephants and rhinoceros in terms of aggression, as these modern animals can certainly be combative without much provocation. The larger sauropods were probably calmer than the smaller ones (less to worry about).
Ankylosaurus and Stegosaurus were probably almost as calm as the sauropods unless danger lurked nearby. Ankylosaurus would hunker down to enable its thick armor to provide protection, and would swing its tail club at any enemy within range. Stegosaurus had 4 long spikes at the end of its tail that would be swung at attackers. In general, plant-eating dinosaurs were probably peaceful at times and perhaps assertive in others. The Ankylosaurus and the Stegosaurus didn't have the huge, intimidating size of the great sauropods, and probably had more predators attempting to attack them. They may have been a bit more aggressive than the sauropods overall, but still not the same level as an elephant or a rhinoceros. However, it can't be ruled out. I would consider a Triceratops potentially aggressive when around others, and there's no reason to think this wouldn't be possible with Ankylosaurus, Stegosaurus, and even some sauropods. If humans could travel back in time and mingle with these animals, I wouldn't feel confident approaching one of them because they might not be comfortable being approached. While these dinosaurs were probably relatively calm most of the time, it's safe to say they were at least "on edge" due to the dangers around.
Sauropods were egg layers. It's likely they would ward off intruders from the nesting area if they could, but the need to abandon the area to eat and drink probably made it impossible to stay with the eggs long enough to keep them safe (if they did this at all). Modern alligators and crocodiles will fiercely defend their nests from predators, but they can't be there all the time. With sauropods however, once the eggs hatched, the mother would probably not have stayed around to avoid stepping on the young. Alligators and crocodiles, by contrast, will care for the hatchlings for a time after birth (sometimes gathering some of the babies in their mouths to transport them safely to the water). Sauropods may have been more like sea turtles in comparison. It's possible the sauropod would leave after the eggs were laid and not return (like sea turtles). Sea turtles will dig the nest and lay the eggs, but once the baby turtles emerge, they are on their own. With sauropods, it not known if the mother reunited with offspring at a later time (assuming they left at all), but it's plausible. It's possible that sauropods did indeed remain with the young after hatching and helped take care of them, but there's not enough information available to know for sure. Many paleontologists disagree on this subject.
There have been many discoveries of fossil dinosaur eggs and the parents in the same location. Some dinosaurs were thought to live in herds and raise families like cattle do today (this is rare in reptiles, though). Protoceratops was believed to defend its nesting sites from egg-eating dinosaurs (like Oviraptor) and defended its young for some time after birth. Other dinosaurs are believed to have been good mothers in much the same way (including Maiasaura, whose name means "good mother lizard").