‘The Big Lizards and Some Later Descendants’

By Zain Mehdi

Meet the Dinosaurs!

Origin of Dinosaurs.....

• More than 200 mya, as North Africa was splitting away from North America, opening up the Atlantic Ocean, hot lava poured out of the Earth. The lava, more than enough to cover the USA, created inhospitable, conditions for most life… except the dinosaurs.

• New geological discoveries suggest this natural catastrophe to be the dinosaurs’ ticket to rule.

Period of Existence

• The age of the dinosaurs is called the Mesozoic Era. It includes the Triassic, Jurassic and Cretaceous time periods.

• According to the current fossils we have found, dinosaurs did not come into existence until the later end of the Triassic Period. That means that for over 100 million years of the Mesozoic Era, there were no dinosaurs on Earth.

The Mesozoic Era

New research suggests that reptiles that lived during the Dinosaur age were hard-hit. Here, the carnivorous lizard Palaeosaniwa chases a pair of young Edmontosaurus while the snake Cerberophis and the lizard Obamadon look on.

During the Mesozoic, or "Middle Life" Era, life diversified rapidly and giant reptiles, dinosaurs and other monstrous beasts roamed the Earth. The period, which spans from about 252 million years ago to about 66 million years ago, was also known as the age of reptiles or the age of dinosaurs.

English geologist John Phillips, the first person to create the global geologic timescale, first coined the term Mesozoic in the 1800s. The Permian-Triassic boundary, at the start of the Mesozoic, is defined relative to a particular section of sediment in Meishan, China, where a type of extinct, eel-like creature known as a conodont first appeared, according to the International Commision of Stratigraphy.

Evolution of Reptiles

Evolution of DinosaursDinosaurs evolved from other reptiles (socket-toothedarchosaurs) during the Triassic Period, over 230 mi-llion years ago. Dinosaurs evolved soon after the Per-mian extinction, which was the biggest mass extinct-ion that ever occured on Earth. During this time (the Triassic period), the mammals also evolved. During the Triassic Period, dinosaur ancestors we-re evolving. In the Jurassic Period, the number of di-nosaurs grew. By the Cretaceous Period, many dino-saur species had evolved.Dinosaurs that could migrate were smaller, but the dinosaurs that were isolated evolved different-ly. Dinosaurs and other organisms have been histori-cally placed into hierarchical categories, using a s-ystem of classification called the Linnaean System.Today, research on dinosaur relationships uses an approach called cladistics, which uses the presence of shared morphological features to rec-reate the branching tree of dinosaur evolution.

Evolution of Birds

Evolution of Mammals

The Linnaean System of Classification

About the Linnaean System• In the 1750s, Swedish botanist Carl von Linne (who is known by the Latin form of

his name, Linnaeus) developed a system to classify all living things. Each living thing has two scientific names, a genus and a species name. The scientist who first describes a new organism names it. Since Linnaeus began using this system, over a million species have been named.

• A scientific name is given in the Linnaean System because living organisms are called different things in different languages. The house cat, for example, is die Katze in German; le chat in French; but English, French and German biologists call it Felis catus.

• In the Linnaean System, similar species are grouped in a genus, similar genera into a family, similar families into an order, similar orders into classes, similar classes into phylum, and similar phyla into a kingdom.

• For example:Dogs, coyotes, wolves: Canis = Canidae Family

• Foxes: Vulpes = Canidae FamilyCanidae and Ursidae Family = Part of Carnivora OrderCarnivora Order = Part of Mammalia ClassMammalia and Fish Class = Part of Phylum ChordateChordate and Coral Phylum = Part of Animalia Kingdom

• These categories are known as taxa (singular: taxon), and the study of these classifications is called taxonomy.

Othniel Charles MarshOthniel Charles Marsh was an American paleontologist. Marsh was one of the preeminent scientists in the field; the discovery or description of dozens of new species and theories on the origins of birds are among his legacies.Marsh died on March 18, 1899, a few years after his great rival Cope. He was interred at the Grove Street Cemetery in New Haven, Connecticut.Born: October 29, 1831, Lockport, New York, United StatesDied: March 18, 1899, New Haven, Connecticut, United StatesNotable award: Bigsby Medal (1877)Books: The Ceratopsia: Based on Preliminary Studies by Othniel C. MarshEducation: Harvard University, Phillips Academy, Yale University, Yale College, Heidelberg University, Sheffield Scientific SchoolNotable student: Charles Emerson Beecher

Charles Robert DarwinBasic Information: Charles Robert Darwin, FRS FRGS FLS FZS was an English naturalist and geologist, best known for his contributions to evolutionary theory.Born: February 12, 1809, The Mount, Shrewsbury, United Kingdom.Died: April 19, 1882, Downe, United KingdomInfluenced by: Jean-Baptiste Lamarck, Alfred Russel Wallace, Charles Lyell, Thomas Robert Malthus, Herbert Spencer, Adam Smith, Alexander von Humboldt, Johann Wolfgang von Goethe, Georges Louis-Leclerc, Comte de Buffon, David Hume, Joseph Dalton Hooker, Adam Sedgwick and John Herschel.Children: Anne Darwin, George Darwin, Francis Darwin, Leonard Darwin, Horace Darwin, Henrietta Litchfield, Charles Waring Darwin, William Erasmus Darwin, Mary Eleanor Darwin and Elizabeth Darwin.

Quotes of Charles Robert Darwin

• It is not the strongest of the species that survive, nor the most intelligent, but the ones most responsive to change.

• A man who dares to waste one hour of time has not discovered the value of life.

• The highest possible stage in moral culture is when we recognize that we ought to control our thoughts.

Cladogram of Clade Reptilia

This is a cladogram of the clade Reptilia (reptiles), tracing the ancestry of these

groups.

Evolution: The Story of Life

Timeline of Evolution

Dinosaur to Man (1)

Dinosaur to Man (2)

Geological Timeline

FACTSFACTSDinosaurs lived millions of years

ago

Dinosaurs lived before people

Dinosaurs existed in the Mesozoic

Era

Dinosaurs mostly hatched from eggs

No dinosaur could fly

Dinosaurs did not live in water

The largest dinosaur was 115 ft long and 50 ft

tall

Dinosaurs became extinct in the

Cretaceous Period

All that’s left of dinosaurs is fossils

Thecodontspronounced: thek-o-don-ts• Thecodonts may have been ancestors of the

dinosaurs.• Thecodonts (like Chasmatosaurus) were socket-

toothed reptiles that were the ancestors of dinosaurs, birds, pterosaurs, and crocodilians.

• These archosauriforms were low-slung, meat-eating quadrupeds had long jaws and a long tail (they looked a lot like crocodiles).

Chasmatosaurus (1)pronounced: kas-mat-o-sor-us• Chasmatosaurus (formerly known as Proterosuchus) is the earliest-

known Proteroschian, a very primitive thecodont that lived during the early Triassic period, about 250 million years ago.

• This socket-toothed, carnivorous reptile had a low-slung body, long jaws with backwards-facing teeth, a sprawling gait, four short legs with five toes on each foot, and a long tail. Its upper jaw turned down at the tip.

• It had teeth on its palate (a primitive feature).• It was about 6.5 ft (2 m) long. This archosaur was an ancestor of the

dinosaurs. • Chasmatosaurus may have hunted herbivorous Dicynodonts like

Lystrosaurus on land but may have also hunted fish in the water. • Fossils have been found in China and South Africa. • Classification: Suborder Archosauria, Order Thecodontia, Suborder

Proterosuchia, Genus Chasmatosaurus

Chasmatosaurus (2)pronounced: kas-mat-o-sor-us

Chasmatosaurus (Skull

Bone)

Anatotitanpronounced: ana-to-tye-tan

• Lived till extinction• 33 feet long• Weighed 7,000 pounds• Plant-eater • Name means: ‘giant duck’• Habitat: Montana and

South Dakota, USA

Triceratopspronounced: try-serra-tops• Three-horned dinosaur• Weighed 12,000 pounds• Cretaceous Period• Plant-eater• Name means: ‘three

horned lizard’• Habitat: Wyoming and Montana in America,

Saskachewan and Alberta in Canada

Gallimimuspronounced: galli-my-mus• Ostrich Mimic (type)• Lizard-hipped dinosaur• Weighed 875-970 pounds• Late Cretaceous Period• Omnivore • Name means: ‘rooster-mimic’• Habitat: Gobi Desert, Mongolia

Minmipronounced: min-mee• Armored Dinosaur• 10 ft long• Weighed 1,100 pounds • Early Cretaceous Period• Plant-eater• Name means: Unknown • Habitat: Grasslands in Queensland, Australia

Tyrannosaurus Rexpronounced: tye-ran-o-sor-us re-ks• Large Meat-eater• 40 ft tall/43 ft long• Weighed 12,000 pounds• Late Cretaceous Period• Name means: ‘tyrant king

lizard’• Habitat: Open Woodland

(North America)

Prenocephalepronounced: pren-o-sef-ah-lee• Bonehead Dinosaur• Weighed 220 pounds• Late Cretaceous Period• Plant-eater• Name means: ‘sloping

head’• Habitat: Gobi Desert, Mongolia

Lesothosauruspronounced: less-oo-tho-sor-us• Herbivore • 3 feet long• Bird-hipped• Biped• Chicken sized• Jurassic Period• Smallest Dinosaur

Ever• Name means: ‘lizard

from Lesotho’• Habitat: Lesotho

Argentinosauruspronounced: aar-jen-teen-o-sor-us• Sauropod• Herbivore• Weighed 115 tons• As long as 3 school-buses• Quadrupedal• Mid-Cretaceous Period• Biggest Dinosaur Ever• Name means: ‘Argentine

lizard’• Habitat: Argentina

Brachiosauruspronounced: brak-ee-o-sor-us• Weighed 80 tons • Equivalent to 17 African

Elephants• 16m tall• 26m long• Jurassic Period• Quadrupedal• Name means: ‘arm

lizard’• Habitat: Tanzania, Kenya and

North America

Sauroposeidonpronounced: sor-o-poz-ie-dun• Brachiosaurid Group• Weighed 36-40 tons• Giraffe-like Stance• Upto 18.5m tall• Tallest dinosaur ever• Mid-Cretaceous

Period• Name means: ‘lizard

of the ancient Greekgod of earthquakes (Poseidon)’

• Habitat: Oklahoma,Wyoming and Texas,America (USA)

Seismosauruspronounced: size-mo-sor-us• Diplodocidae Group• Herbivore• Weighed 30 tons• 18 ft (5.5m) tall• 130-170 ft (39-52 m)

long• Saurischian• Sauropodomorph• Type Species:

S.hallorum• Longest Dinosaur

Ever• Late Jurassic Period• Name means: ‘quake

lizard’• Habitat: New Mexico,

USA

Troodonpronounced: troo-don• Hunter Animal• Carnivore• Brainiest Dinosaur Ever• 2m long• Late Cretaceous Period• Brain size similar to

modern mammal orbird

• Stereoscopic Vision• Biped• Name means: ‘wounding

tooth’• Habitat: Wyoming, Montana

and Alberta in Canada

Velociraptor (1)pronounced: vel-o-see-rap-tor• Biped• Had about 80

very sharp,curved teeth

• Teeth were 2.5 cm long

• The head was about 7 inches (18 cm) long

• 5-6 ft long• 3 ft tall• Weighed 7-5

kgs• Late Cretaceous

Period• Dromaeosaurid Group• Name means:

‘speedy thief’• Habitat: China,

Russia, Mongolia• Speed: 40 mph (60 km/hr)

Velociraptor (2)pronounced: vel-o-see-rap-tor

• A 3.5 inch (9 cm) long, sickle-like, retractable claw was on the middle toe of each foot. This claw was its main weapon, and could probably kill most of its prey (defenseless plant-eaters like hadrosaurs) easily.

Velociraptor (Labeled)

Stegosauruspronounced: steg-o-sor-us• Brain size of a

walnut (only 3cmlong)

• Brain weighed 75g• Weighed 3800kgs

(2 tons)• Sauropodomorph• Quadrupedal• Jurassic Period• Name means: ‘roof lizard’• Habitat: U.S Midwest

(Colorado, Oklahoma, Utah)

Micropachycephalosauruspronounced: my-cro-paky-sef-ah-lo-sor-us• Longest Name• Ornithischian• Weight: Unknown• Late Cretaceous Period• Name means: ‘tiny

thick-headed lizard’• Habitat: Shandong

Province, southwestof Laiyang, China

• Found by: ChinesePaleontologist, Dong (1978)

Eoraptorpronounced: ee-o-rap-tor• Scientific Name: Eoraptor

lunensis• Oldest Known Species• 228 million years old• Early Triassic Period• Name means: ‘dawn thief’• Habitat: Ischigualasto Formation, Argentina, South

America and Madagascar

Mesosauruspronounced: mez-o-sor-us• Swimming Reptile• 3 ft long• Weight: Unknown• Early Permian Period• Ate small ocean

animals• Name means: ‘middle

lizard’• Habitat: coastal areas of

Southern Africa and South America

Eudibamus (1)pronounced: yoo-dee-bam-us• Eudibamus cursoris was a small, fast-moving lizard that lived during the Permian

period, roughly 290 million years ago. It is the earliest-known animal that walked on two legs (it was facultatively bipedal; it ran on two legs when it needed to).

• Eudibamus' hind legs were long, and its front legs were short and weak (the hind legs were 64% longer than the front legs and 34% longer than its trunk).

• It also had a long tail. • This plant-eater used its speed to avoid its predators.• It was 10.3 inches (26.1 cm) long.• David Berman (of the Carnegie Museum of Natural History) estimated that

Eudibamus could run about 15 miles per hour (24 kmph).• Fossils of this synapsid were found in a quarry near Gotha, Germany, in 1993. • Eudibamus was named by Robert Reisz, et al. • Eudibamus was not a dinosaur, but another, much earlier type of reptile.

Dimetrodon was a contemporary of Eudibamus. • Classification: class Reptilia (reptiles), order Eosuchia, suborder Bolosauridae,

family Bolosauridae, Genus Eudibamus, species E. cursoris.

Eudibamus (2)pronounced: yoo-dee-bam-us

E.cursoris

Eudibamus (Described)

Elasmosauruspronounced: ilaz-mo-sor-us• 46 ft long• Longest of Plesiosaurs• Carnivore• Late Cretaceous Period• Not a dinosaur• Tetrapod• Diapsid• Sauropterygia• Plesiosaur• Plesiosauroid• Went extinct in K-T mass extinction (65 mya)• Had gizzards• Laid eggs on sandy shores• Name means: ‘thin-plated lizard’• Habitat: Wyoming, USA

Pteranodonpronounced: terr-an-o-don• Flying Reptile• 30 ft long• Wingspan: Upto 40 ft• Weighed 40 pounds• Late Cretaceous Period• Ate small ocean animals• Name means: ‘winged lizard’• Habitat: Germany, France,

England, Tanzania

Quetzalcoatluspronounced: qoo-et-zul-kot-lus• Quetzalcoatlus was a giant pterosaur from the

late Cretaceous period, and the largest flying animal ever.

• It was named by Lawson in 1975. • Classification: Pterodactyloidea, Azhdarchidae

Quetzalcoatlus (Picture)

Quetzalcoatlus (Cladogram)

dN

eoaz

darc

hia

Thalassodromidae

Dsungarapteridae

Chaoyangopteridae

Azhdarchidae

Thalassodromeus sethi

Tupuxuara leonardii

Tupuxuara longicristatusDomeykodactylus ceciliae

Dsungaripterus weiiNoripterus complicidensNoripterus parvus

Eoazhdarcho liaoxiensis

Shenzhoupterus chaoyangensisChaoyangopterus zhangi

Jidapterus edentusRadiodactylus langstoni

Azhdarcho lancicollis

Zhejiangopterus linhaiensisArambourgiania philadelphiaeQuetzalcoatlus northropiQuetzalcoatlus sp.

Archaeopteryx (1)pronounced: ark-e-op-ter-iks• Archaeopteryx (meaning "ancient wing") is a

very old prehistoric bird dating from the Jurassic period, about 150 million years ago.

• It had teeth, feathers, three claws on each wing, a flat sternum (breastbone), and a long, bony tail.

Archaeopteryx (2)pronounced: ark-e-op-ter-iks

Archaeopteryx (Labeled)

Microraptor (1)pronounced: mike-ro-rap-tor• Microraptor (meaning "little plunderer") is a newly-

discovered, bird-like dinosaur from China.• This crow-sized coelurosaurid theropod was about 16 inches

(40 cm long). Its feet were adapted for climbing; it may have spent much of its life in trees.

• This bipedal meat-eater had some bird-like features, including its teeth (like those of early birds) and hip (it had a Rahonavis-like ischium). A partial skeleton (missing the middle portion) and feather-like impressions were found in Liaoning, China.

• It is probably an adult, but this is not certain. The type species is M. zhaoianus; it was named by Xu, Zhou, and Wang in 2000.

Microraptor (2)pronounced: mike-ro-rap-tor

Microraptor (Size Comparison)

Wooly Mammoth (1)pronounced: woo-lee mam-uth• Lived 2 mya

to 9,000 yearsago

• Cenozoic era(Last Ice Age)

• Pleistocene toearly Holocene Epoch

• Known fromfossils and cave drawings

• Cave paintings foundin France and Spain

• Herbivores• 9 ft (2.7 m) tall to

over 15 ft (4.5 m) tall• Weighed 3 tons (2.75 tonnes)• Ears much smaller than

modern-dayelephants

• Related to IndianElephants

• Both males/femaleshad tusks

• Tusks were over 17 feet(5.2 m) long

• Mummified Mammothfound in Siberian Ice

• Habitat: Tundras of Asia,Europe and North America

• Scientific Name: Mammuthusprimigenius

Wooly Mammoth (2)pronounced: woo-lee mam-uth• Classification:

Mammoths are mammals and classified as follows: Kingdom AnimaliaPhylum ChordataClass Mammalia (mammals)Subclass Eutheria (Placental mammals)Order ProboscidaeSuborder Elephantoidea (3 families, 2 of mastodons and 1 of mammoths)Family Elephantidae (mammoths and modern elephants)Genus MammuthusSpecies

• M. primigenius (the woolly mammoth, from late Pleistocene Europe and North America - 9 feet=2.7 m tall, a small mammoth) • M. planifrons (the flat-browed mammoth, from Pleistocene India) • M. meridionalis (the southern mammoth, from early Pleistocene Europe - one of the first mammoths - 15 ft=4.5 m tall) • M. imperator (the imperial mammoth, from early Pleistocene North America, about 2,000,000 years ago - 13 ft=4 m tall with

tusks just as long) • M. jeffersoni (the mammoth, from Eurasia) • M. columbi (the Columbia mammoth, from late Pleistocene North America 12 ft=3.7 m tall with twisted tusks) • M. trogontherii (the steppe mammoth, from middle Pleistocene central Europe 15 ft=4.5 m tall with tusks 17 ft=5.2 m long) • etc. • Anatomy and tusks: Woolly Mammoths had long, dense, dark black hair and underfur, long, curved tusks, a fatty hump, a

long proboscis (nose), and large ears. They were about 11.5 feet (3.5 m) long, 9.5 feet (2.9 m) tall at the shoulder and weighed about 3 tons (2.75 tonnes). The tusks were used for protection, in interspecies dominance, and for digging in the snow of the ice ages for grass and other food. (Classification: Family Elephantidae)

• Extinction: The Woolly Mammoth probably went extinct because it couldn't adapt to the combined pressures of the climatic warming that occured when the Ice Age ended, together with predation from humans.

Wooly Mammoth (Described)

American Mastodon (1)pronounced: um-err-ic-un mast-o-don• Mastodons were large, widely-distributed mammals that are now extinct. These quadrupeds

were well adapted to the cold weather; they were large (which retains body heat), had thick, insulating fur, and had long tusks, which they may have used to push through the snow to obtain food.

• Diet: Mastodons were herbivores (plant-eaters) who ate the leaves of tree leaves, shrubs, mosses, twigs, and other plants. Some mastodons have been found with food in the mouth or stomach.

• Anatomy: Mastodons had long, brown, shaggy fur and two large, upper tusks. Mastodons were smaller than modern-day elephants; they ranged from about 6.5-10 feet (2-3 m) tall at the shoulder.

• Evolution and Extinction: Mastodons evolved in Africa about 35 million years ago and spread throughout Africa, Europe, and Asia. About 3.7 million years ago, mastodons migrated to North America via the Bering Strait land bridge. The last of the mastodons went extinct about 10,000 years ago, when the last Ice Age ended.

• Mastodons were closely related to the mammoths and the elephant.

American Mastodon (2)pronounced: um-err-ic-un mast-o-don

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(Mammut americanum)‘breast tooth’

American Mastodon (Described)

Saber-Toothed Catspronounced; sabe-er too-th-ed cat-s

These extinct cats are notable for two huge canine te-eth plus other sharp teeth in powerful jaws. These m-ammals also had powerful jaw and neck muscles thatlet them stab prey with their deadly teeth. They ate mammoths, rhinoceros and other thick-skinned anim-als.Examples include: Smilodon (the largest and most po-werful, from N. America) Hoplophoneus (with short t-eeth, from the Oligocene), Eusmilus (leopard sized w-ith very long teeth, from the Oligocene) and Machair-odus (lion-sized and common; from Europe, during the Paleocene). Fossils have been found in Pliocene to early Pleistocene rocks from both North and South America and other northern continents

Smilodon (1)pronounced: smy-lo-don• Largest Saber-Toothed Cat• 4-5 feet (1.2-1.5 m) long

and 3 feet (0.9 m) tall• Weighed about 440 lbs (200 kg)• a bit smaller than a modern-day

lion (Panthera leo), but muchheavier

• Had short legs and a short,bobbed tail

• adapted for springing onto prey, but not a very fast runner

• 12-inch-long (30 cm) skull• Had 2 huge canine teeth• Jaws that opened to an

angle of about 120°• Teeth were serrated• 7 inches (18 cm) long• Last Ice Age, Pleistocene

Epoch (early part of Quaternary Period)

• Habitat: grasslands, shrubby areas, andpine forests that supported theplant-eating animals that saber-toothcats ate

• Ate mastodons, horses and bison

Smilodon (2)pronounced: smy-lo-don• Fossils

Thousands of Smilodon fossils have been found in late Pleistocene tar pits and rocks from North America (S. californicus, which is the California State Fossil, and S. fatalis have been found in California) and South America (S. neogaeus has been found in Argentina).

• ClassificationPhylum: ChordataClass: Mammalia (mammals)Order: Carnivora (cats, dogs, bears, seals, weasels, etc.)Family Felidae (cats)Subfamily Machairodontinae (saber-toothed cats)Genus: SmilodonSmilodon was named by Plieninger in 1846.

• MeaningSmilodon means ‘knife tooth’

*Smilodon and the other saber-toothed tigers are not closely related to modern-day tigers.

Eusmilus (1)pronounced: yoo-smy-lus• Eusmilus was a saber-toothed cat that lived during the late

Eocene (about 40 million years ago) in Eurasia, and spread eastward over the Bering land bridge to North America by the Oligocene Epoch. Fossils have been found in France and the USA (in North Dakota, South Dakota, and Wyoming).

• This predator had long, saber-like upper canine teeth, but only 26 teeth in its mouth (most carnivores have about 44 teeth). Its huge jaws could open about 90 degrees, allowing it to stab its victims with its incisors. Eusmilus was about 8 feet (2.5 m) long; it had a long, low body and a long tail.

• Classification: Superfamily Feloidea (cats, mongooses), Family Felidae, Subfamily Machairodontinae, Genus Eusmilus, species cerebralis, etc.

Eusmilus (2)pronounced: yoo-smy-luss

Machairodus (1)pronounced: maa-kai-rod-us• Machairodus was a common saber-toothed cat that

lived from about 15 million years ago until about 2 million years ago.

• Species of this scimitar cat have been found in Africa, Europe, Asia, and North America.

• This lion-sized meat-eating mammal had slender limbs and a short tail; the upper jaw canine teeth were large.

• Machairodus was named by Kaup in 1833. • Classification: Family Felidae, Subfamily

Machairodontinae, Genus Machairodus, many species.

Machairodus (2)pronounced: maa-kai-rod-us

Hoplophoneus pronounced: hop-lo-fon-ee-us• Hoplophoneus was a relatively small saber-toothed cat (about 1 1/2

to 2 times the size of a housecat) that lived during the Oligocene Period (from about 40 million to 20 million years ago).

• Fossils have been found in Wyoming, USA. • This cat's skull was 6 inches (15 cm) long.• This predator had long, saber-like upper canine teeth that fit into a

socket in its lower jaw. • Hoplophoneus was plantigrade (flat-footed, unlike modern-day cats,

which are digitigrade).• Its large jaws could open about 90 degrees, allowing it to stab its

victims with its incisors. • Classification: Superfamily Feloidea (cats, mongooses), Family

Felidae, Subfamily Machairodontinae, Genus Hoplophoneus

Hoplophoneus (Size Comparison)

Number of Species found in Britain (United Kingdom)

• So far, 108 species have been discovered in Britain. Britain was an important area during much of the Mesozoic Era acting as a “land bridge” between North America and Eurasia. It became a hotspot for dinosaur evolution and migration.

• British dinosaurs include Megalosaurus, Iguanodon, Neovenator, Eotyrannus and Cetiosaurus.

How do we know so much about them, eh?

Fossils! Lots and lots of fossils!

Archaeologists found dinosaur claws. They were very sharp, so they were used to kill prey. They were the claws of a meat-eating dinosaur(s).

These are fossilized Hadrosaur eggs.

Smallest/Biggest Dinosaur Egg

• SMALLEST• Only 3cm long• Species Unknown• BIGGEST• As big as a football• Species Unknown• Bigger than biggest ostrich

egg

• Dinosaurs died out 65 million years ago.• We do not know why. Some think because of…• Climate Change • Meteorite Shower• Sea Level Change What do you think?

Extinction of Dinosaurs

• Dinosaurs completely died out 65 million years ago.

• Dinosaurs survived for more than 165 million years before the Earth was hit by a massive meteorite originally believed to have caused their extinction, according to new research.

It is universally believed by most people that dinosaurs died out 65 mya when a big asteroid or meteorite hit the Earth. Ten years later, scientists found the 65 million year old, 180km wide, Chicxulub crater on the Yucatan Peninsula in Mexico, which finally provided the smoking gun that could explain the apparent chaos at the end of the Mesozoic era. A crater that wide suggests that an asteroid or comet approximately 10km wide hit the Earth.