cambrian explosion

What is an animal? You asked me in the hall 

A multicellular eukaryotic heterotroph with no cell walls! 

You tell me you want me to go more in specific, 

Well, just sit here and listen to the lyrics, 

Only 3% of all animal species are Vertebrates! 

And 97% of all animal species are Invertebrates! 

Those percentages are comparable to murder rates! 

You can find symmetry in all kinds of species, 

Me and you and you and me have bilateral symmetry! 

That means that we are built with proper consistency! 

Primitive animals are built with radial symmetry, 

That is comparable to when you cut a pie evenly. 

I was brought here to give you education, 

On the evolution trend of specialization! 

“What is Specialization?” you might ask, 

Primitive Animals have no specialized tissue in their body mass! 

“Mr. Francis! We never learned about Cephalization in class.” 

Well, hold on tight I'm just getting to that. 

Cephalization is the concentration of nerve organs, 

Meaning that, you would feel your sore gums. 

Primitive animals don’t have this system, 

All they have is a simple neutral net kingdom! 

“Francis Cruz thank you for sharing this wisdom” 

The development stages is as short as a prism! 

The sperm and the egg meet and create a zygote, 

And goes through mitosis to end up as a white goat, 

But it’s not as simple as it gets like that, “Teach us!” 

It goes through multicellular division to become a fetus! 

Now don’t lose attention just yet, listen to me, 

Every animal has 3 germ layers, I guarantee! 

The endoderm becomes the gut, 

The ectoderm becomes the skin on your butt! 

And lastly to finish off this scene 

The mesoderm is the layer in between! 

Now I hope you learned a bit from what was spoken, 

Animals were born from the Cambrain Explosion!