Horseshoe to the modern hoof boot. Historians differ on the origin of the horseshoe. Because iron was a valuable commodity, and any worn out items were generally reforged and reused, it is difficult to locate clear archaeological evidence. Although some credit the Druids, there is no hard evidence to support this claim. In 1897 four bronze horseshoes with what are apparently nail holes were found in an Etruscan tomb dated around 400 B.C. The assertion by some historians that the Romans invented the "mule shoes" sometime after 100 BC is supported by a reference by Catullus who died in 54 BC.
Greater horseshoe bat kHz, have most energy at 81 kHz and have an average duration of 37.4 ms. The greater horseshoe bat is the largest horseshoe bat in Europe. It has a distinctive noseleaf, which has a pointed upper part and a horseshoe shaped lower part. Its horseshoe noseleaf helps to focus the ultrasound it uses to 'see'. The greater horseshoe bat also has tooth and bone structures that are distinct from that of other rhinolophids. Its first premolar on the upper jaw protrudes from the row of teeth. For other horseshoe bats, this premolar is very small or non-existent. Also in comparison