The earliest Prehistoric animals to live were jawless, spineless creatures that roamed the oceans about 540 million years ago. It wasn’t until the Devonian period, 400 million years ago, when the prehistoric creatures grew legs and left the ocean, these are the prehistoric ancestors to all vertebrate creatures on earth today. Once on land, the prehistoric creatures underwent a bunch of different adaptations for running, crawling, flying, and jumping; it was then when the rise of the dinosaurs took place, in the Triassic period about 230 million years ago.
Even though the dinosaurs ruled, many small, rodent-like mammals were alive and these small mammals, along with some birds, amphibians, and reptiles survived the mass extinction that wiped out the dinosaurs. Although 90% of the species that have lived on Earth throughout its existence are extinct, most of the creatures that survived this first mass extinction still exist today.
The factors that cause animals to go extinct are mainly the loss and degradation of habitat which is mainly due to deforestation. Other causes for animals going extinct are exploitation through hunting and overfishing, invasive species, and climate change. Plastic pollution and emerging diseases are also factors that play a role in the extinction of animals.
Extinct animals have not successfully been brought back as of today. Scientists need to sequence its genome and then edit the DNA of a close living relative to match it. Afterwards, they would need to make embryos with the revised genome and have a surrogate mother carry them.
Animals that have gone extinct because of climate change include the golden toad and the north Atlantic cod is threatened. The staghorn coral and orange-spotted filefish have also had their population numbers affected by the effects of climate change. It is up to humans to make the necessary changes and help endangered animal species.