-
Cambrian 570-500 MYA
The Cambrian Period is the first geological time period of the Paleozoic Era (also known as the “time of ancient life”). The Cambrian period lasted approximately 53 million years ago. Many animals that were present within this time period were the chordates, animals with a dorsal nerve cord; hard-bodied brachiopods, which resembled clams; and arthropods, ancestors of spiders, insects and crustaceans.The word ‘Cambrian’ was named after the Roman for Wales. -
Silurian Period 435m-395m MYA
Reef systems flourished in the clear, tropical seas evident today. Limestone rock formations dated back to this period. The development of corals and other marine organisms were aroused by oceans teeming with tiny planktonic creatures. Moreover, the food chain animals consisted of eurypterids or sea scorpions. Several breeds grew to more over six feet (two meters) in length and are considered the largest arthropods ever to have lived. -
Ordovician Period 500m-435 MYA
Echinoderms creatures were starfish, sand dollar, sea urchin and sea cucumbers. Invertebrates are dominant. Mollusks become abundant, they are the earliest jawless and armored fish. -
Devonian Period 395m-345 MYA
Armored fish go extinct, but an abundance of several species are fish. Also, the earliest amphibians, large swamps and coal appear. About 416 million years ago the Devonian period began. The Devonian, part of the Paleozoic era, is also known as the ‘Age of Fishes,’ groups of new fishes are born. The newly fish placoderms first appeared during the Silurian. There strong jaws lined with sharpie plates act as teeth. These placoderms digested mollusks and other invertebrates. -
Carboniferous 354m-290m MYA
Rays and modern sharks became common. Sea urchins and sea stars (starfish) thrived; coral reefs continued to grow. Diatoms, a type of shelled plankton, made their first radiation into the ocean. The Cretaceous period was the heyday of the dinosaurs. Huge carnivores like Tyrannosaurus rex and Giganotosaurus adapted in this environment.The breakup of the supercontinent Pangaea separated into continents. The separation of Laurasia and Gondwana was complete. Global sea levels were high. -
Premian Period 280m-225m MYA
The Permian period contained the largest mass extinction the earth has ever known, almost 299 million years ago. The southern part was cold and most, with a frozen region of ice caps. Northern areas were humid, also wet and dry. Swamps and forests were gradually replaced by conifers, seed ferns, and other drought-resistant plants. Early reptiles were well placed to capitalize on the new environment. Amphibians became ideally suited to the desert-type habitats in which they thrive today. -
Period: to
Mesozoic Period 248m-65m MYA
The Mesozoic era is the period in which dinosaurs lived and its end was marked by the K-T extinction. This extinction event dramatically changed the Earth’s flora and fauna, and its causes are still being investigated. -
Trassic Period 225m-195m MYA
The common animals that were involving during this time period were the dinosaurs, ammonites, mollusks, and sea urchins that survived the Permian extinction. The very first corals appeared. In addiction, giant reptiles were born as well, such as the dolphin-shaped ichthyosaurs and the long-necked and paddle-finned plesiosaurs that preyed on fish and ancient squid. At the bottom of the food chain were microscopic plants known as phytoplankton. -
Jurassic Period-195m-136m MYA
Birds, mammals, dinosaurs, and rodents were abundant. Crumbling landmasses and inland seas appreared. Sea monsters, sharks, and blood-red plankton live in the deep blue oceans. Forests of ferns, cycads, and conifers. Warm, moist, tropical breezes. At the beginning of the Jurassic period the supercontinent Pangaea and its Mountains rose on the seafloor, pushing sea levels higher and onto the continents. -
Cretaceous Period 136m-65m MYA
The Cretaceous period ended 65 million years ago with the extinction of the dinosaurs. The Cretaceous period is named after ‘chalky rock’ that comes from southeastern England and it was the first sediment studied. Cretaceous mammals included the rise and extinction of the toothed birds (hesperornis and ichthyornis). Fossils of birds also were discovered, Other mammals during this time period include grebes, cormorants, pelicans, flamingos, ibises, rails, and sandpipers. -
Tertiary Period 65m-1.8m MYA
Birds, bony fish, sharks and other new species were present in the Tertiary time period. Bees and other insects relied on pollen and nectar from the flowering plants. The cooling climate contained enormous glaciers at the poles. Mountains of the ancient world were covered by glaciers which formed the Himalayas and Alps. Also, placental mammals, modern mammals, and large running mammals existed. -
Quaternary Period 1.8m-1.25m MYA
During the Quaternary time period the temperatures were freezing and thawing. Sea levels rose and there were glaciers. Mammals with furry coats stayed cozy and warm in this climate. Large carnivores, Neanderthals, and various human species lived in this time zone.
