There once was an Ichthyosaurus
That lived when the earth was all porous
It fainted in shame
When it first heard its name
And passed on a long while before us.

- Unk.


Key words or concepts:
Vertebrate (also called Chordata)
Pisces (Cambrian to Recent)
Amphibia (Devonian to Recent)
Reptilia (Carboniferous to Recent)
Aves (Jurassic to Recent)
Mammals (Triassic to Recent)
useful terms
gills
amniote egg
ectothermic
endothermic
Placental
Marsupial
Ornithischian
Saurischian
Archeosauria

Useful links:

Earth Science Picture of the Day

Return to Historical Geology syllabus