How wrinkled is your brain?

Found on the Smithsonian blog today about the differences in brain size and whether the animal has a smooth brain or a wrinkled brain.  Which are similar and which are different?  In the article Nuwer makes observations of how three of the animals have brains that are shaped as a liver.  Very interesting.  Why does she say this?  What shape is a liver?

Great image from the blog mentioned above to learn about shapes, patterns and even math.  I say math because they did give us a scale at the bottom of the image that students can measure each brain to get an idea about the size and area.  Tracing, they could place a thin sheet of paper over each brain and trace the brains.  Make a lapbook and take this even more in depth and study each animal.  Lots that can be made just by this one article.  I am not an evolutionary thinker so I can read this without wondering why the brains are so similar because I know I did not start as a monkey or evolved from the grey squirrel.