There are three major families of shorebirds: 1  Waders, about 220 species, include sandpipers, lapwings, snipes, plovers, stilts and various other species. These birds inhabit coasts and shorelines, as well as other open habitats. 2  Gulls, terns, skuas, jaegers and skimmers form a group of a little over 100 species.
The compass was probably invented in the Qin Dynasty (221-206BC) by Chinese fortune-tellers who used the lodestones to construct their fortune telling boards.
The origin of the compass is shrouded in mystery. Certainly the Greeks knew about the attractive properties of magnetism in ancient times. Similarly, the Chinese were probably aware that an iron bar stroked with a lodestone acquired a directional north-south property as long as 2000 years ago.