Carnivorous dinosaurs are night hunting species

The first evidence of dinosaur eyes on fossils shows that carnivorous dinosaurs do not sleep at night but are awake to hunt.

Researcher Lars Schmitz of the University of California and colleagues examined the eyes of fossil dinosaurs. They studied the width of the eye socket, the size of the sclera, the ring around the iris in birds, reptiles and dinosaurs (humans and other mammals without bones) and compared with animals. vertebrates include birds, reptiles and mammals.

Nocturnal animals need to maximize the amount of light, so they open their eyes as loudly as possible. The daytime animals have lots of light to see, their eyes are not fully open to reduce the energy used, causing the pupils to tighten to reduce the amount of light entering, and also help them see clearly and practice centered on images in depth.

In contrast, other animals are more active during the early morning and evening or irregular times of the day including herbivores, some birds, hairy tatu, large South American pythons and dogs. Their eyes need to look at both width and depth, so the hard membrane is of medium size.

Fossils of dinosaurs eat grass, species operate both day and night. (Photo: Livescience )

In dinosaur fossil samples, the researchers looked at the ratio of some eye characteristics to determine the behavior of the species. They look at the aperture of the sclera, pupil and eye socket to determine the diameter of the eye, as well as the diameter of the epidural shore to find the length of the eye.

Like modern winged species like falling and birds, most flying dinosaurs, including three species of flying lizards and four bird dinosaurs, are awake all day. However, five flying dinosaurs have nocturnal behavior or change their routine, including two that have a habit of breeding some night birds today.

Most herbivorous dinosaurs change periodic activity. For herbivores, such as elephants and herbivorous dinosaurs Protoceratops andrewsi, eye size indicates that they spend a lot of time eating and operating. Large animals are also easily overheated, so they often avoid heavy activity during the day to avoid the sun's temperature by switching to night activities.

Predators, including dinosaurs and today's species, are advantageous when hunting at night. And all the carnivorous dinosaurs studied by scientists are night-hunting or changing routine.