history of the Earth

Fossils are the geologically altered remains of a once-living organism and/or its behaviour. They can be formed in few different ways but the most common way is permineralisation. It occurs when dissolved minerals carried by ground water fill up space inside the cells of plants and animals.The dissolved minerals crystalise in these cellular spaces and eventually form rocks in the shape of the animal or plant. Another way is when the organisms remains are decomposed entirely, leaving an empty space in the shape of the organism, it can be later filled with minerals and form a mineralised 3D shape of the organism. Sometimes, organisms leave behind indications of their behaviour such as tracks, nests or burrows. These fossilised behaviours are known as trace fossils. Soft tissues can also be preserved. They form in special circumstances that often need rapid burial and low oxygen environments that stop the organism from decomposing or being scavenged by other organisms. These cir...

With a 11 to 12-m wingspan, Quetzalcoatlus is the largest flying organism ever known. This gigantic pterosaurs lived around 70 million years ago, probably in an environment inhabited also by the Tyrannosaurus and Torosaurus. Over the years belives, beliefs about how it flew and how it hunted changed. Latest studies says that Quetzalcoatlus was flying occasionly and only for short distances but it was a strong flyer when it did fly. It would probably have used its powerful hind legs to launch as high as 2.4 m when taking off. The most accepted hypothesis is that it lived like a stork and that it would hunt small prey like mammals, lizards and possibly small dinosaurs on land while also utilizing small streams and pounds to catch fish and crustaceans. Because of its size and flight capability it probably didn't have to worry about predators too often.  sources: https://www.google.com/search?q=quetzalcoatlus+compared+to+a+human&tbm=isch&ved=2ahUKEwiI3crl-_CBAxVEgosKH...

Synapsids are one of the two major clades of vertebrate animals that evolved from basal amniotes (a group of tetrapod vertebrates), the other being the diapsids, which include reptiles and birds. What distinguished them from diapsids was development of a single temporal opening on the side of the skull. Around 280 million years ago climate started to change which caused many groups of primitive reptilian and amphibians to rapidly decline. Aynapsids instead adapted to the new conditions and dominated the earth. Over time synapsids evolved into many different forms from carnivores to herbivores. At the end of the permian period took place the biggest mass extinction in history of our planet. After that synapsids that didn't extinct started competing with reptails. Dinosaurs quickly replaced them and only smaller ones which adapted to the new environment survived. They endured the cretaceous extinction which killed dinosaurs. New mammals filled many different ecological niches and spr...