Telltale Dino Heart Hints at Warm Blood
He could tell just by looking that this dame had a heart of stone.
![](https://i0.wp.com/www.sciencenews.org/wp-content/uploads/2002/10/1805.jpg?resize=150%2C129&ssl=1)
When PI (paleontological investigator) Michael (Mike) Hammer stumbled across the big-eyed dinosaur that he calls Willo on a South Dakota ranch in 1993, he noticed her chest cavity right away. Preserved in the curve of the dinosaur’s ribs was a rock that Hammer was convinced was a heart.