Dinosaurs

English paleontologist Richard Owen coined the term dinosaur. The word originates from the Greek words Denis and Sauers. Denis means terrible, and Sauros means lizard. That means its whole meaning is a terrible lizard.

In the early twentieth century, scientists thought that dinosaurs were slow-moving, short-sighted, and cold-tempered creatures. But later, their perception changed.

Different species of dinosaurs

Some of these species were carnivores, and some were herbivores. Some species could walk on two legs. Again, some species walked around. Some were about 100 feet high, and some were as tall as chickens. About 500 species of dinosaurs have been discovered so far. However, based on the fossil record, it is believed that 1850 species have been found. That means about 75% of the species are still waiting to be discovered.

However, an earlier study found that there were 3,400 species of dinosaurs on Earth. Most of which do not exist in the surviving fossils. Dinosaurs roamed every continent of the world. Evidence of its existence has been found even in Antarctica.

Below are some notable names for many species of dinosaurs.

Saurischia: These dinosaurs were like reptiles.

Theropods: This is a group of carnivorous dinosaurs.

Sauropods: They survived by eating herbs. They had very long necks.

Ornithischia: These are herbivores who have bird-like lips.

Armored dinosaurs: They had large bones on their backs that protected them.

Ornithopoda: These are “duck-billed” dinosaurs.

Pachycephalosaurus: The heads of these dinosaurs were very stiff.

Ceratopsia: These belong to the horned race.

Dinosaurs vary in size and shape from species to species. It was 12 meters (39 feet) high and 22.5 meters (74 feet) long. And the weight was 30,000 to 60,000 kg. There is also the T-Rex which was 40 feet long and 15 to 20 feet high.

Diplodocus was another species of dinosaur that was 27 meters (89 feet) long. They discovered its existence in America. Notable among the giant herbivores is Argentinosaurus zar weighing 80,000 to 100,000 kg. The Diplodocus halloumi is 33.5 long (110 feet), 33 meters long Supersaurus, 18 meters (59 feet) high Sauroposeidon. Some of the notable carnivores are Giganotosaurus, Carcharodontosaurus and Tyrannosaurus.

Dinosaurs are not just giant animals. The smallest dinosaur Anchiornis weighed 110 grams. 

Like other animals, dinosaurs lived in groups. Moreover, maternal behavior was also evident among them. The infancy of some species was comparatively more extended than that of other species.

Reasons for the extinction of dinosaurs:

The exact cause of dinosaur extinction is not yet fully known. However, many scientists believe that dinosaurs became extinct due to a large meteorite hitting the Earth hard. According to them, the meteorite was about 15 kilometers long, and its impact was one billion times stronger than that of an atomic bomb.

However, some believe that the extinction of dinosaurs was caused not by meteor strikes but by volcanic eruptions. Moreover, many people think that lack of food is a significant reason. At the time, carnivorous dinosaurs ate herbivorous dinosaurs, leading to food shortages.

Temperature changes can also be considered as a significant factor.

Due to giant dinosaurs’ slow and stagnant movement and the dirty environment, they fall prey to various viral and bacterial diseases. And thus, many think that at one time, it was on the way to extinction.

However, another factor that is predominant in the extinction of dinosaurs is the thickness of their eggshells. Experiments have shown that the shell of an egg six and a half million years ago was much thicker than the shell of an egg 12 to 14 million years ago. As a result, it was difficult for the baby dinosaurs to break their eggshells. It would later lead to dinosaur deformities and reduced fertility. Thus, at one time, they were heading towards extinction.