Practicing Animals Using Box Shapes

Taken from the book, "Wildlife Sketching" by Frank Lohan, I practiced a few animals using his box shape examples.

It's one thing for me to follow already laid out box shapes.........it's another to actually visualize them when looking at an actual animal.  You'd think looking at something and working with shapes would be easier but it doesn't really work for me.....at least broken down shapes within a subject.  My eyes see the overall shape and stops there.