Text Leveling System

Dinosaur Babies

RDQ:	671	Max Word/Sent	27	Total Words	1157		Diff Words	392
Lex	670	Ave Word/.Sent	11	Hi Freq occurs	700	60.5%	Hi freq	140	35.7%
AR	3.1	Long Sentences	5.2	Low Freq occurs	92	8%	Low freq	60	15.3%

Inside her egg the tiny dinosaur baby squirmed.
She bumped the eggshell with her snout and her egg
began to crack.
She pushed with her legs.
The top of the egg popped open and she wriggled out.
Bits of damp eggshell stuck to her head.
She shook herself and toppled over on her chin.
She was a maiasaur born more than 70 million years
ago. What was life like for a baby maiasaur or for any
baby dinosaur?]]
Most of the dinosaur skeletons we see in the museum are huge.
Imagine a dinosaur baby small enough to hold in your arms.
What would happen to this tiny creature in a world of giants?
Was she left to fend for herself? Or did her gigantic parents take
care of her?
It is hard to tell what kind of parents dinosaurs were. Fossils tell
us almost everything we know about dinosaurs. But for most types 
of dinosaurs fossils are scarce.]]
Some animals alive today are related to or are similar to
dinosaurs. When fossils are few scientists often study living
dinosaur relatives. These animals can help us understand
how dinosaurs might have behaved.
The lizards turtles and crocodiles of today are reptiles.
Dinosaurs were reptiles too. Most reptiles lay hard-shelled 
eggs.]]
We wouldn't call lizards
and turtles the greatest parents.
They lay their eggs and forget
about them. When the babies
hatch they are on their own.
Maybe some dinosaurs were
like lizard parents.
But of all the reptiles dinosaurs
are most closely related to crocodiles.
Crocodiles make nests and fiercely
guard their eggs from enemies.]]
Since dinosaurs are more closely related to
crocodiles than they are to turtles or lizards it
is possible that some dinosaurs were nest guarders.
But Maiasaura were not fierce like crocodiles. They
were peaceful creatures who spent their days browsing
on bushes and sipping at streams.
Were the Maiasaura lazy-lizard parents? Or were they
protective parents like crocodiles? Scientists
believe they have been different from both.]]
Birds of today are also related to dinosaurs.
Like reptiles all birds lay hard-shelled eggs.
Most birds are careful parents. Not only do they build
nests to protect their eggs they also feed and watch over
their babies until they are old enough to leave the nests.
Scientists believe that some dinosaurs might have behaved
like bird parents. For Maiasaura an amazing number of
fossil clues help to prove they did.]]
In Montana scientists discovered a group of ancient Maiasaura
nests filled with fossil eggs and babies. Near the nests were the 
bones of an adult maiasaur: (The name Maiasaura comes from
Greek words meaning "good mother lizard.")]]
The fossils tell us that a baby maiasaur started her life inside a
small oval egg. The eggs of her brothers and sisters surrounded
her in the great hollowed-out mound that was their nest.]]
When the baby hatched she was small and scrawny. She was
hungry but her legs were wobbly. She could not toddle out of
the nest on her own. Like baby birds she and her newly hatched
brothers and sisters probably squawked for their mother.]]
And what a huge mother she was! The newborns
were about 18 inches long - that's about how long you
were when you were born. Their mother was nearly the
size of a school bus. Her enormous head loomed over the
edge of the nest. But her babies were not scared.]]
She held sweet berries in her mouth. The babies scrambled
toward her and gobbled up the berries. Then they probably
hunched together and fell asleep. While they slept at least
one grown-up stayed near the nest to protect them.]]
Small deadly meat-eating dinosaurs called Troodon may have
prowled the nesting grounds in packs. If Troodon were allowed
to raid the nests many babies would be carried away for Troodon
snacks. Maiasaura parents were watchful. If a troodon attacked a
maiasaur could stomp on it with its huge hind legs.]]
When a maiasaur baby was big and strong enough she would
follow her mother out of the nest. Fossils tell us that a young 
maiasaur may have stayed with her parents for many years.
Not far from the nesting grounds scientists found a vast area
covered with Maiasaura bones. Some of the bones belonged to
youngsters and some to adults.
Scientists believe that these are the remains of a Maiasaura
herd. The adults in the herd would have protected the youngsters
from the ferocious tyrannosaurs called Albertosaurus that stalked
the area. Sadly the members of this particular herd must have
died all at once when a volcano erupted spewing hot ash and
deadly fumes.]]
Today many types of birds gather together in nesting grounds
much like the Maiasaura's. And some travel in flocks much like the 
Maiasaura herds.
We know that bird eggs need to be kept warm so they can
hatch. Most birds sit on their eggs to keep them warm. Dinosaur
eggs needed to be kept warm too. But the 4000 pound maiasaur
moms could never have sat on their eggs. If they had the eggs
would surely have been crushed!
Bits of fossilized plants in the nests hint that perhaps maiasaurs
covered the eggs with leaves
and branches. As the leaves
rotted they would have
warmed the eggs.]]
Smaller leaner dinosaurs such as Troodon and Oviraptor may have
sat on their nests to hatch their eggs the way birds do.
In the dry country of Mongolia scientists have found many nests 
and a few skeletons of the Oviraptor.
In some ways the Oviraptor even looked like a bird. It had 
long legs a toothless beak and a crest on top of its head.
Oviraptor skeletons are very rare. Even so three
oviraptors have been found lying on top of their
nests. Oviraptors must have stuck by their
nests with great determination.]]
Whether oviraptors took care of their babies after they were
hatched no one is sure. But there is an interesting clue.
Two tiny skulls of meat-eating dinosaurs were
found in one of the oviraptor nests.
Did the mother oviraptor raid the nests of other
dinosaurs returning with the tiny babies to feed
her own young? That is one possibility. Scientists
hope that as more fossils are found we may 
be able to tell for sure.]]
Like lizards and turtles some dinosaurs probably laid their eggs 
and never thought about them again.
But we now know that maiasaurs and oviraptors and possibly
many other types of dinosaurs built nests and guarded them.
And some dinosaurs must have fed and protected their babies
for months or even years. Life in the lad of the giants may
not have been as terrifying as we thought.
Next time you go to the museum take a look at
Tyrannosaurus rex. What kind of mom do you
think she'd be? She may look pretty scary
to you but to her babies she might have
been as gentle as a bird.]]

Subjective Criteria

Illustrations: Some support

Vocabulary: Some difficult words

Language: Few descriptive words

Sentences: Multiple phrases

Text structure: Oral/Natural

Inferences: Some implications

Features

Difficult names

Foreign words

Topic

Dinosaurs

*Animals

Animals: Prehistoric

*Animal Life

Low Frequency Words

albertosaurus	determination	fend	ferocious	fiercely
fossil	fossilized	gigantic	gobbled	guarded
guarders	hatched	herd	herds	hind
hollowed	hunched	maiasaur	maiasaura	maiasaura's
maiasaurs	mongolia	montana	mound	nesting
newborns	newly	oval	oviraptor	oviraptors
particular	peaceful	possibility	protective	prove
prowled	related	relatives	rotted	scarce
scrambled	scrawny	shelled	similar	sipping
spewing	squirmed	stalked	surely	surrounded
terrifying	toothless	toppled	troodon	tyrannosaurs
tyrannosaurus	watchful	wobbly	wriggled	youngsters