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 to be separate species produced fertile hybrid offspring freely, and in other cases what were considered to be mere varieties of the same species could only be crossed with difficulty. Darwin concluded: "Finally, then, the facts briefly given in this chapter do not seem to me opposed to, but even rather to support the view, that there is no fundamental distinction between species and varieties." In the sixth edition Darwin inserted a new chapter VII (renumbering the subsequent chapters) to respond to criticisms of earlier editions, including the objection that many features of organisms were not adaptive and could not