Did dinosaurs reach their maximum size?

Scientists believe that titanosaurs It grew rapidly And they didn’t slow down until they reached their gigantic adult sizes. “When we compare their growth rates throughout life to [those of] live animals, they are closer to the growth rates we observe in whales. That’s incredibly fast,” says Rogers.

Rogers adds that, unlike whales, titanosaurs did not benefit from consuming the high-protein, nutritious milk provided by their mothers. Instead, these dinosaurs were foraging for their own food. “Keeping their growth rates high is one way most sauropods differ from their meat-eating dinosaur relatives, which seem to have stunted their growth a lot as they got older.”

And while titanosaurs were the largest sauropods, Carano points out that their ancestors among the sauropods were really big. “Evolution to 70-80 tons from a 20-30-ton ancestor probably didn’t require that much evolutionary innovation,” he says. It shows that all structures and systems are already set up to achieve success in huge volumes.

Skywalker, a field assistant at Altitude Science Institute for Natural History Exploration, which conducts fieldwork in Montana and Wyoming. “This allowed them to have varied diets, which gave them access to a range of nutritious foods,” she says.

Because of their increased size, sauropods developed “air” air sacs in their bones, to make their skeleton lighter. “These air sacs were made up of soft tissue attached to the lungs,” Walker says. “This made their weight easier to bear and allowed for a more efficient supply of oxygen throughout their body. Unlike mammals, sauropods had this thanks because there are almost no limits to how far they can grow.”

Predatory dinosaurs It had pneumatic air sacs, as do modern-day birds, says Carano, and these sacs may have evolved from a common ancestor. However, it is also believed that they have developed independently in other groups, including pterosaurs and sauropods. “This would increase breathing capacity and soften these massive bones without sacrificing their strength.” Carano explains that sauropods had short feet and column-like limbs to support their massive weight. “These are all traits taken to extremes in the largest titanosaurs,” he says.

Titanosaurs also had adaptations hidden in their joints. Smaller, non-avian dinosaurs like t-rex They had tight joints where their bones meshed neatly, like ours. In contrast, titanosaurs had joints with enormous sizes of spongy cartilage at the ends of their bones. This difference in joint structure, especially in major limb joints like the hip, she says, is thought to be an adaptation to better maintain the animal’s massive body weight.

However, according to Carano, what’s less clear is how the titanosaurs managed to outpace their sauropod ancestors. Perhaps they simply had more time to develop larger bodies, after the departure of their Jurassic ancestors. On the other hand, they may have acquired a new innovation – modifying their existing anatomy so that they are larger. “But there isn’t much difference that makes the answer clear. It’s also possible that they may have benefited from the availability of new foods, especially flowering plants, that didn’t exist in the Jurassic period,” says Carano.

The jury is still out on whether titanosaurs might have gotten bigger, had the dinosaurs not gone extinct.

“I think there may have been sauropods that were somewhat larger, but not significantly,” Carano says. He says it helps to think in terms of “orders of magnitude,” which technically refers to change by factors of ten, to think about major shifts in scale. For example, going from 1 ton to 10 tons is a big deal, he says—much more than going from 10 to 20 tons. “There is a shift in scale in the former but not the latter.”