Dinosaurs’ behavior has been researched for a long time. Scientists have tried to find out more about their habits and to make comparisons with modern animals in similar ecological niches. Besides the fact that these creatures used to travel in herds, researchers have recently found out that male dinosaurs were the ones who would take care of the nests, eggs and baby dinosaurs.

The article about the findings was published on Thursday in the journal “Science” and the scientists wrote that this behavior can be seen in some existing species of birds. It has been long known that researchers have tried to discover things about the dinosaurs by looking at their closest living relatives, the crocodiles and the birds.

It has been long though that birds developed from small and feathered predatory dinosaurs more than 150 million years ago.

Troodon, Oviraptor and Citipati are the three types of dinosaurs who used to watch over their nests and babies. They lived almost 75 million years ago and, as Montana State University paleontologist Frankie Jackson, one of the researchers, stated, there are a lot of features they believed unique in birds and which were later discovered to have come from dinosaurs.

According to fellow Montana State University paleontologist David Varricchio, this type of behavior only occurred among large birds like emus and rheas and the South American tinamous. The dinosaurs were left with nests which contained 22 to 30 eggs they had to guard. The remains were found in Montana in the case of Troodon, and Mongolia in the case of Oviraptor and Citipati.