Reptile

  

 A  T  O  P  O  D  E  N  T  A  T  U  S

This is one of those I see it but I don't believe it moments.

What advantage is there in having a hammerhead snout

for a mouth?  The mass extinction of life at the end of

the Permian, left entire ecosystems drained of the normal

pushback provided by others.  Before, you had to fight

for everything you needed.  Just taking up space

required conflict with those around you. 

Mass extinction has emptied the streets.

You can stroll into Macy's when you like 

and take off with what you want.  Every day.

Genetically speaking, animal designs developed 

in this type of environment that would not 

survive the normal competitive stresses

of just existing.  These extraordinary times

brought about both innovators as well as 

a healthy batch of quacks.

The process of genetics is driven by blindness.

Its course is set only by trial and error.

T  A  N  Y  S  T  R  O  P  H  E  U  S  

Genetic design gives clues to the animal's context -

its environment.  In this instance, an advantage

was gained by having a neck more than half the

length of its own body.  Is this ungainly length used

to reach vegetation high up or does it make grabbing

fish easier when hovering from above?

How do you keep ths animal from falling on its face

when out of water?  The bones of the neck are hollow

to save weight.  To counterbalance the head and neck

the animal has an enormous pelvis with massive 

hind legs and a long tail.  These are steps taken to

prop up a fundamentally unstable design.

This line of genetics was doomed once the right

species of predator was introduced into its 

environment.  Carnivores learned to target

the neck, because decapitation was a relatively

easy way to bring the animal down.

Extravagance comes with built-in vulnerability.

P  L  E  S  I  O  S  A  U  R

 

 Here is a classic marine design from the Triassic period.

The plesiosaur survived tens of millions of years, well

into the Jurassic period that followed.  Pictured above

is a spectacular fossil from the time preceding the 

Age of Dinosaurs.  Look at the enormous fins.

They are limbs strengthened with solid bone.

The flipper becomes an oar to paddle the animal

swiftly through the watery realm.  The tail operates

as a rudder for navigation.

The fin's skeletal structure starts with a single large

bone that divides into several digits, each having 

multiple joints to give the fin nuance to its sweep

through the water.  This sophisticated design enabled

the plesiosaur to maneuver like a sea lion, 

or even a dragonfly.

 

S  P  I  N  O  S  A  U  R  U  S

 Crocodile jaw.  Predator.  About the height of a 

two story home.  Neural spines extend five feet

into the air.  Could be used for thermoregulation,

much as the ear of an African elephant is used

to disperse heat into the surrounding air

or to absorb energy from the early morning sun.

The hind legs are longer but the front limbs

are more massive, with large pronounced digits

armed with claws.  The large vertical tail propels

the animal when swimming.  

It's the Creature from the Triassic Swamps. 

S  P  I  N  O  S  A  U  R  I  D  S

The Spinosaurus family gathered together,

all from the same lineage but each from

a different period in time.  The crocodile

grin is iconic to this family of species.

In runs on two legs, using its tail for balance.

The shorter forearms are designed for grasping.

Among this group is the Spinosaurus with 

the five foot neural crest, splashed with color

imaged by the artist.  The use of vibrant color

usually means one of two things:  either it is

meant to lure a mate or to be identified as a 

member of a particular species.  

It's a tribal thing.

 

 

 

 

 

T   A   W   A         H   A   L   L   A   E 

 It's Late Triassic, 215 million years ago,

the first therapsids, dinosaurs, show up 

in the fossil record.  The Tawa, Hopi language

for Sun God, was discovered in New Mexico,

Land of Enchantment.

The specimen illustrated here is about the 

size of a large dog, thirty-five pounds,

and walks on two legs.  Its reptilian head

could well be the basis for the skull of a

modern day raptor, like that of a hawk.

The Tawa had a highly efficient respiratory system

much like the one used by the birds we see daily.

It is possible this early dinosaur had already

come to use feathers for insulation.

These factors don't make this animal a bird

but it is evidence of bird characteristics

found in the earliest known species of dinosaurs.

 

 

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©  Tom Taylor

  

OVER   EASY

 

 

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