Crown-of-thorns starfish received their common name from the needle-sharp spines that cover their arms and body that supposedly resemble the biblical crown of thorns. Their scientific family name – Acanthaster - means almost the same thing. In Latin, Acanth means thorny and aster means star. COTS prefer their food alive – and luckily for them coral doesn't go anywhere fast. The starfish have an exclusive diet of stony coral, preying on the polyps that make up the coral's soft tissues. They project their stomach from their mouths, covering an area almost as big as they are. Their digestive juices liquify the coral beneath and the starfish absorb the meal. They then invert their stomach back inside their body.