Percy the Plesiosaur's Evolution 

By Katlin Griffin 

Percy the Plesiosaur

The Plesiosaur is a dinosaur that lived during the Mesozoic era at the beginning up until the end of the Cretaceous period. Plesiosaurs were alive 199 million years ago. 

The Plesiosaur lives in the water, and eats fish, mollusks and other sea creatures. They had sharp teeth and flippers to help propel itself through the water. It it most-likely that it is a carnivore because of it's teeth.  Since it breathed air, it needed to come up to the surface once in a while to breathe. 

Natural Selection 

What is Natural Selection?

 Natural selection is when an organism becomes better adapted to its' environment to make more offspring. For example with a type of bird; if the bird has a longer beak, it may use it to get insects like grubs and worms while a bird of the same species could have a different beak so it could eat leaves.

Genetics

How did genetics affect Percy?

How did genetics change Percy's offspring? With the planet warming, some dinosaurs decided to find a new place to live. They did this by...

...migration. Since there isn't enough water for Percy to live and grow in, he decides to swim away and find a new place to live. He finds an island with his Plesiosaur girlfriend Penelope, for the two of them to live together. Now, they are separate from the rest of their species. This causes their gene pool to split. A gene pool is a group of ALL of the Plesiosaur's genes that live together but now that Percy and Penelope are away from their species, their gene pool will split. After Percy and Penelope decide if they want to be parents, we can see what their children will look like and what they might have.

Percy's Migration

Percy and Penelope's Offspring 

Pictured on the right, is a Punnett Square. A Punnett Square helps show what Percy and Penelope's kids would look like. As you can see, the father, Percy, has a dominant gene. This is represented using "B". The mother, Penelope, has two recessive genes, which are represented by "b". No matter where Percy's dominant gene goes, it will always be on top because it's "bigger". Once you drop down the letters to the correct boxes, you'll see that the order is Bb, Bb, bb, and bb.

 

 

Bb

 

 

 

 

 

 

 

Bb

 

 

bb

 

 

 

 

 

 

 

bb

One of Percy and Penelope's kids had a mutation! Their child PJ has gills! That is one of the most helpful mutations that he could've gotten! They had a few more children who also had the mutation. They can all swim without needing to return to the surface for air, which is very helpful. 

The Mutation 

As PJ and his siblings grew up, they started to make families and gave their children gills since it was a dominant gene. This is how a new species of Plesiosaur was made.