Lung Evolution

Lung Evolution

To the tune of “Stand By Me” by Ben E. King

[Verse 1] 
Lungs likely evolved
In the common ancestor
Of the bony fishes
Homologous to
The swim bladder
Lungs evolved from air bladders

[Chorus]
All lungs are fluid lined
And are highly vascularized
They cyclically will change size
Will change size

 [Verse 2]
All lungs have cells
Producing surfactant
Preventing adhesion of the lung
Gills lack surfactant
So in air lamellae
Stick together and cannot be used for breathing

[Chorus] x2 
All lungs are fluid lined
And are highly vascularized
They cyclically will change size
Will change size