ITT anons point out elements of pokemon designs that you think other anons might not have realized or noticed

Riolu is supposed to give the feel of a domestic fighting puppy, so it has those teardrop things situated to look like false droopy puppy ears and this little yellow collar around its neck. When it evolves into the wilder and more mystic Lucario the floppy puppy "ears" change to become the ends of its headband/mask over its face and the collar moves to its shoulders and turn black where they now look like martial arts bands, while the yellow remains in Lucario's torso fur color. That's why Lucario has those shoulder donuts and what the deal with those teardrop things are.