Were Dinosaurs Ectothermic or Endothermic?

The article is a re-analysis of a widely publicized 2014 Science paper on dinosaur metabolism and growth that concluded dinosaurs were neither ectothermic nor endothermic -- terms popularly simplified as 'cold-blooded' and 'warm-blooded' -- but instead occupied an intermediate category.

Were dinosaurs ectotherms or endotherms?

When the researchers examined how fast dinosaurs grew, they found that the animals resembled neither mammals nor modern reptiles, and were neither ectotherms nor endotherms. Instead, dinosaurs occupied a middle ground, making them so-called "mesotherms."

Are all dinosaurs endothermic?

In addition, even the most ancient dinosaur-like relative, Marasuchus, may have been endothermic based on the data from the hip study, Pontzer says, suggesting that endothermy evolved very early on in the dinosaur lineage. Therefore, the results also suggest that all dinosaurs were endothermic, the team wrote.