Rock of Gibraltar Rock of Gibraltar The Rock of Gibraltar, also known as The Rock, is a monolithic limestone promontory located in the British overseas territory of Gibraltar, near the southwestern tip of Europe on the Iberian Peninsula. It is high. Most of the Rock's upper area is covered by a nature reserve, which is home to around 300 Barbary macaques. These macaques, as well as a labyrinthine network of tunnels, attract a large number of tourists each year. The Rock of Gibraltar was one of the two Pillars of Hercules and was known to the Romans as "Mons Calpe", the other pillar
On the Origin of Species were descended from one species of rock pigeon. Darwin saw two distinct kinds of variation: (1) rare abrupt changes he called "sports" or "monstrosities" (example: Ancon sheep with short legs), and (2) ubiquitous small differences (example: slightly shorter or longer bill of pigeons). Both types of hereditary changes can be used by breeders. However, for Darwin the small changes were most important in evolution. In Chapter II, Darwin specifies that the distinction between species and varieties is arbitrary, with experts disagreeing and changing their decisions when new forms were found. He concludes that "a well-marked variety may be justly called