Page:Palæolithic Man and Terramara Settlements in Europe.djvu/37

Rh evolutionist. The reconstructed skeleton of the Diplodocus Carnegii, a gigantic extinct reptile from the Upper Jurassic Age in North America, and now exhibited in the Natural History Museum, London, is a most striking object-lesson in the records of extinct animal life.

Degeneration.

There is another principle bearing on the variation of both plants and animals, which I cannot do better than introduce to you in the words of Sir Edwin Ray Lankester:—

The inference to be deduced from these facts is that the origin, duration, and extinction of species have been largely regulated by circumstances outside the organism itself. Why the Pearly Nautilus should survive to the present day, while those huge terrestrial reptiles which came into existence at a much later period have entirely disappeared, is a problem which cannot be easily answered. Are we to suppose that such monsters as the Diplodocus, which measured 84 feet in length and 12 feet 9 inches in height, or the Atlantosaurus, which attained a length of over 80 feet and a height of 30 feet, or the huge Iguanodon, whose semi-erect skeleton stands 14 feet in height, were not able to hold their own in the struggle for life? Several circumstances in the ever-changing environment might be advanced as adequate causes of their extinction. For instance, the submergence of extensive areas of land, or the appearance on the scene of better equipped competitors, which would either kill them in fight or deprive them of their customary food. That brute strength gives way to cunning and strategy is not a peculiarity of human actions alone. The tiger, seeing the carcase of his prey on which he has just feasted devoured by birds, has no power of retaliating on the