Check out the size of that sponge! Seriously, its a sponge, aptly named the "Giant barrel".  But as awesome as this sponge is to look at, its not so awesome if your a coral.  Research by Joe Pawlik and colleagues released this week suggests that overfishing of fish that love to tuck in to a bit of sponge means sponges are taking over on some coral reefs.  There's a nice overview of the paper or alternatively if you fancy reading the paper yourself you can - it's open access!