Two striped shore crabs (<i><a href="https://en.wikipedia.org/wiki/Pachygrapsus_crassipes" class="extiw" title="w:Pachygrapsus crassipes">Pachygrapsus crassipes</a></i>) and two small shells on a rock at <a href="https://en.wikipedia.org/wiki/Redondo_Beach,_California" class="extiw" title="w:Redondo Beach, California">Redondo Beach</a>'s King Harbor Marina &amp; Pier - <a href="https://en.wikipedia.org/wiki/California" class="extiw" title="w:California">California</a>, U.S.A. The one on right is pushing the one on left to take over a lunch spot. If you zoom in, you can see that the crab on left is still holding a piece of food with its left claw.
<a href="//commons.wikimedia.org/wiki/User:Nandaro" title="User:Nandaro">Nandaro</a>
CC BY-SA 3.0
<span class="int-own-work" lang="en">Own work</span>