Dinosaurs evolved to have smaller brains as they became bigger, scientists discover

They’re known for their horns, but dinosaurs known as ceratopsians (of which the classic triceratops is one example) evolved to have a reduced sense of smell and a smaller hearing range, according to researchers from the US and China – with one study author issuing a warning about what this means for human beings.

A non-technical summary of the article, which was published by Cambridge University Press in October, reads: “The horned dinosaurs underwent great changes throughout their evolution, including a shift in the locomotor mode (from bipedal to quadrupedal posture), enlargement of horns and frills, and increase in body size.”

Bipedal and quadrupedal refers to a shift from using two legs to four legs, by the way.

It continues: “Here, we use virtual analytical methods to reconstruct the endocast of extinct dinosaurs and examine the evolution of the endocasts of horned dinosaurs that display some unique structures associated with auditory sense and smell.

“Based on the dataset and analytical detail on endocranial structures, we found that early-diverging horned dinosaurs (e.g., Yinlong and Psittacosaurus) had a high olfactory acuity and were adapted to hearing high frequencies, whereas the late-diverging horned dinosaurs (e.g., Triceratops) possessed lower olfactory acuity and hearing frequency.”

The researchers also note that earlier ceratopsians – which, as mentioned above, started off smaller – were “more encephalized”, so had larger brains.

In other words, as they became thicker, they… well… became thicker.

And dinosaurs evolving to rely less on their senses has prompted a warning from one of the study’s authors.

Dr Fenglu Han, of the China University of Geosciences in Wuhan, told South China Morning Post: “People have become increasingly dependent on technologies with the rise of mechanisation and artificial intelligence … These findings of dinosaurs remind us not to become too dependent.

“While dinosaurs had no control over their evolution, humans, with our advanced brains, should be able to manage our behaviours and choices.”

It’s not the only interesting thing science has uncovered about dinosaurs, or what we humans can learn from them, as one study suggests some of the animals had the ability to control their own body temperature, while another said they might be responsible for us aging so quickly.

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