The Paleozoic ends with the extinction of almost all Mammal-like Reptiles.

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The Paleozoic ends with the extinction of almost
all Mammal-like Reptiles.
And MANY other species!
The Mesozoic begins with an explosion of new
types of reptiles evolving
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The Mesozoic what happened when?
Early Mesozoic
Cretaceous
First Dinosaurs
First Mammals
Jurassic
they laid eggs!
Triassic
First Snakes, Crocodiles, Turtles
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Late Mesozoic
Big (and little) Dinosaurs
Cretaceous
Little Mammals(still!)
Jurassic
First Birds
Triassac
First Flowers and other Modern Plants.
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Also during the Mesozoic
Giant (and small) Flying Reptiles
which apparently had fur, and MAY have been
warm-blooded.
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We know that Pterosaurs laid eggs!
Intact egg with complete embryo Pterosaur!
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Giant (and small) Sea Reptiles
Ichthyosaurs
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We know that Icthyosaurs evolved from land
reptiles
But how does a terrestrial reptile reproduce when
it no longer can return to land?
Live Birth!
From Ryosuke Motani
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Plesiosaurs
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Mosasaurs
None of these sea or air creatures were Dinosaurs!
Flying and Sea Reptiles were other branches of
reptiles, now extinct not Dinosaurs.
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Dinosaurs!
Stupid? maybe
Slow? ...probably not!
Dinosaurs were active creatures
And a diverse group!
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The presence of Large Claws on the feet of
Velociraptor they must have been able to leap
and slash (like Jurassic Park!).
Dinosaurs were apparently able to outcompete
Mammals (so they MUST have been active creatures?)
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Dinosaurs have been found in colder placeslike
Alaska. Alaska was warmer in the Mesozoic, but
the LONG nights would have been hard for a big
reptile to survive.
So were they reptiles?
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Some Dinosaurs traveled in herds hundreds of
skeletons have been found together in a single
volcanic ash bed.
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At least some Dinosaurs took care of their young!
The discovery of larger baby dinosaurs (not
newborns) still in the nest means that the
parents were taking care of them.
Fossil of Oviraptor on its nest!
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Some species nested in large colonies like many
Birds do today.
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Birds
Birds evolved from Dinosaurs!
Their skeletal structure is similar.
The earliest birds known had claws on their
wings, long bony tails, and teeth in jaws (not
beaks!).
Feathered Dinosaurs have now been found!
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This little Dinosaur was a juvenile Raptor! It
was fully feathered. An unusual fossil find, the
skeleton is complete.
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Many other feathered Dinosaurs are known!
Luis Rey
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In the last few years, scientists have discovered
melanosomes in Dinosaur feathers!
Melanosomes produce color pigments in feathers.
Melanosomes not only tell us WHAT color some
Dinosaurs were
(The shape of a melanosome varies with the color
produced.)
..they also show that the structures are indeed
feathers!
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What an UTTERLY different Mesozoic World we can
now envision!
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Fossils now show that some juveniles had
different plumage than the adults
Julius Csotonyi
FORTY species of feathered Dinosaurs are now
known!
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Brian Choo
Large feathered Dinosaurs have been recently
discovered
at 30 feet long, and1.5 tons, YUTYRANNUS was a
fluffy and deadly carnivore!
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The End of the Mesozoicthe End of the Dinosaurs!
The great Mesozoic Extinction...
left no land animal bigger than 100 pounds on
the planet.
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Why??? No one is surea Meteor or Comet impact
wrecking the Earths ecology for years seems a
likely culprit.
Meteors have a higher percentage of IRIDIUM that
Earth materials
and a layer of Iridium-rich clay is found right
on the top (at the end) of the Mesozoic at places
around the World!
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Orperhaps a changing environment triggered by
immense volcanic eruptions which ARE known to
have happened at about that time.
Or a combination of two or more factors???
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Whatever the reason
MANY types of animals and all the Dinosaurs
Died out! ?
This extinction included all flying and all
marine reptiles
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with some notable exceptions!
"Green turtle swimming over coral reefs in Kona"
by Brocken Inaglory.
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On to the Cenozoic Era!