Discovering Dinosaurs

Discovering Dinosaurs — page 5 — Museums are good places to learn about dinosaurs 10

Discovering Dinosaurs — page 6 — How Do We Know about Dinosaurs Our knowledge of dinosaurs and their world is based on stone with the minerals in the stone replacing the original biological material the fossil record The word fossil comes from the Latin language and means from the ground Fossils occur when If the find is considered a new kind of dinosaur the scientist gets to name it remains of animals and plants are preserved in layers of Even without formal training you can still look for fossils check out one removed from the surrounding rock back at the museum or university the lead scientist will write a description of the find in an article for publication of the young paleontologists clubs across the country In fact many important almost completely Dinosaur bones are the most commonly found fossils but discoveries have been made by amateur fossil hunters skin and feather impressions footprints eggs some with fossilized embryos inside and even dinosaur dung are also found Paleontology is the study of the fossil remains of ancient life and the interpretation of what they mean Paleontologists also known as paleobiologists must study geology biology anatomy and other disciplines to gain the expertise needed to accurately describe the fossils they find Dinosaur fossils are generally found in remote locations around the world referred to as the field and scientists delve into the earth to find them Our Earth is made up of layers called strata They are like the pages in a book each atop the earlier one The places where paleontologists probe for fossils are called dig sites Once the dinosaur fossils have been collected and carefully prepared 11 Theropod footprint Fossils must be carefully removed from the rock surrounding them

Discovering Dinosaurs — page 7 — Where and When Did Dinosaurs Live The Mesozoic Era which means middle life when dinosaurs were the dominant vertebrate terrestrial animals occurred from 252 million to 65 million years ago During this time period the map of the world was very different than it is today At the beginning of this Age of Dinosaurs there was only one super continent which we call Pangea Over millions of years Pangea began to break apart into separate continents as seas and oceans flowed into the widening gaps between the separating land masses This process called continental drift continues today The Mesozoic Era is divided into three periods the Triassic 252 to 208 million years ago the Jurassic 208 to 145 million years ago and the Cretaceous 145 to 65 million years ago During the Triassic the early dinosaurs were able to travel across the whole of Pangea but after the continents began to drift apart the movements of later dinosaurs became more and more restricted This allowed for dinosaur diversity on each of the isolated continents and dinosaur fossils have been discovered on every continent 12 Triassic map Jurassic map Cretaceous map

Discovering Dinosaurs — page 8 — Dinosaurs and Hips Dinosaurs share a common ancestor that probably looked much like the small Triassic thecodontian reptiles Ornithosuchus and Lagosuchus pelvic bones the ilium ischium and pubis radiate out from the hip socket as in reptiles with the pubis pointing forward The bones in the Ornithischian dinosaur pelvic structure on the other hand are parallel to the ischium and All dinosaurs are divided into two large orders based on the shape the pubis is rotated backwards as in birds The Saurischians are further of their hips These groups are the Saurischian lizard hipped and divided into two suborders the carnivorous theropods terror foot and the Ornithischian bird hipped In Saurischian dinosaurs the three the generally huge herbivorous sauropods lizard foot Ornithosuchus Lagosuchus 13

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