Hermit crab gives rise to the popular name "hermit crab", by analogy to a hermit who lives alone. Several hermit crab species, both terrestrial and marine, have been observed forming a vacancy chain to exchange shells. When an individual crab finds a new empty shell it will leave its own shell and inspect the vacant shell for size. If the shell is found to be too large, the crab goes back to its own shell and then waits by the vacant shell for up to 8 hours. As new crabs arrive they also inspect the shell and, if it is too big,
Fiddler ray Fiddler ray Trygonorrhina, also known as the fiddler rays or banjo rays, is a genus of guitarfish, family Rhinobatidae. The two species are found along the eastern and southern coasts of Australia. They are benthic in nature, favoring shallow, sandy bays, rocky reefs, and seagrass beds. The eastern fiddler is found to a depth of 120 m and the southern fiddler to a depth of 180 m. The flattened pectoral fin discs of fiddler rays are shorter and more rounded than those of other guitarfishes. Their tails are slender, with a well-developed caudal fin and two triangular dorsal fins. Their