Finding Past (Dinosaur) RMS Jinnah Campus Gujrat Grade 2

What ARE Dinosaurs Dinosaurs are a group of reptiles with a set of physical features that are different from those of all other reptiles. They include extinct animals we know from fossils and the birds we see today. The extinct animals we normally think of as dinosaurs had their heyday in the Mesozoic. The word ‘dinosaur’ means ‘terrible lizard’ in Greek.

What ARE Dinosaurs

Physical Features Hole in skull between eye socket and nostril Two holes in skull behind eye socket Ankle that bends in single plane like a hinge Hip socket with hole in center Limbs held directly under the body Three or more sacral(located near pelvis) vertebrae

Physical Features

Meet the family Just like a family tree shows your ancestors and present-day relatives, an evolutionary tree shows how dinosaurs are related to other groups of animals and to each other. Dinosaurs (those that are extinct and living birds) are part of the evolutionary tree of amniotes. The first amniotes were primitive four-legged reptiles from which all other reptiles and mammals evolved. One branch of early reptiles led to the archosaurs – the group that includes dinosaurs, crocodiles and pterosaurs. Dinosaurs themselves are split into two main groups based on their hip structure, and then smaller branches based on other shared features.

Early dinosaur relatives The oldest known relative of the dinosaurs is a dog-sized four- legged animal called Asilisaurus kongwe, that lived about 240 million years ago. The fossil bones of at least 14 individuals were discovered in Tanzania. Asilisaurus belonged to the group of animals called silesaurs, which were closely related to dinosaurs. Silesaurs continued to live alongside dinosaurs until near the end of the Triassic, about 200 million years ago. These fossils show that the dinosaur lineage had already split from dinosaur-like relatives by at least 240 million years.

The rise of dinosaurs When dinosaurs first appeared in the Middle Triassic, about 230 million years ago, they were simply another group of small reptiles in a world full of reptiles. By the end of the Triassic they dominated life on land and would for another 140 million years, till the close of the Mesozoic.

Dinosaurs Came in All Shapes and Sizes Types Dinosaurs Came in All Shapes and Sizes

There are more then 700 species in the World.

Types

Major Types of Dinosaurs There are 15 major types of Dinosaurs

1. Tyrannosaurs Tyrannosaurus (ty·ran·no·saur·us) meaning "tyrant lizard king" Simply known as T. rex

Sauropods and Titanosaurs were the biggest dinosaurs ever.

3. Ceratopsians (Horned, Frilled Dinosaurs) Plant eating Dinosaurs

4. Raptors a genus of dromaeosaurid theropod dinosaur that lived approximately 75 to 71 million years ago

5. Ankylosaurs (Armored Dinosaurs) a heavily armored dinosaur with a large club- like protrusion at the end of its tail. Ankylosaurus means "fused lizard" in Greek

6. Dino-Birds feathered dinosaur

The “duck-billed” dinosaurs 7. Hadrosaurs The “duck-billed” dinosaurs

8. Ornithomimids ("Bird Mimic" Dinosaurs) a group of theropod dinosaurs which bore a superficial resemblance to modern ostriches. They were fast, omnivorous or herbivorous dinosaurs

9. Ornithopods The Ornithopoda are a group of medium to large plant-eating dinosaurs. They include one of the earliest discovered dinosaurs

10. Pachycephalosaurs (Bone-Headed Dinosaurs) an unusually small family of dinosaurs with an unusually high entertainment value

11. Prosauropods Lizard Footed Form

12. Stegosaurs (Spiked, Plated Dinosaurs) small-to-medium-sized, small-brained herbivores were characterized by the double rows of plates and spikes along their backs and the sharp spikes on the ends of their tails

13. Therizinosaurs 'to reap' or 'to cut off' and "sauros" meaning 'lizard‘ It could grow up to 10 meters (33 feet) long and reach 5 tonnes in weight.

14. Assorted Theropods Wild Beast

the last surviving group of long necked dinosaurs 15. Titanosaurs the last surviving group of long necked dinosaurs

Why they become Extinct? The last dinosaurs died approximately 65 million years ago There are many theories about why and how Dinosaurs became Extinct

Why they become Extinct? Asteroid Theory Volcanic activity Ice Age Theory Disease Gradually changed in climate Competition from Other Animals New Discoveries (strange ideas)

Theories

Theories

Conclusion Let’s clear something up right away. Dinosaurs aren’t extinct. Not entirely. Every magpie, pigeon, penguin, and ostrich alive today – every single bird – is a dinosaur. They’re all descendants of small, toothy, feathery dinosaurs that hopped and fluttered around from the Jurassic era onwards, meaning that birds are dinosaurs in the same way that bats are mammals.