Domesticated Animals and Plants; A Brief Treatise Upon the Origin and Development of Domesticated Races, with Special Reference to the Methods of Impr

This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1910. Excerpt: ... CHAPTER V THE WAY OF THE WILD The astonishing abundance of life. The struggle for existence. Selective effect of the natural conditions-Competition for food-Competition for room Competition most severe between individuals of the same species. Natural selection. Survival of the fittest. The individual and the race. Significance of numbers. Significance of vigor and length of life-Significance of offensive and defensive weapons. Significance of protective coloring and markings. Mimicry. Design in nature. Causes of color in animals and plants Before we can discuss to best advantage the means of further improving our animals and plants it is necessary that we understand as well as possible the conditions and habits of life to which they were accustomed in the natural state before they came to us, because out of this we shall evolve a method of procedure for further improvement. The astonishing abundance of life. The most conspicuous fact in nature is the astonishing abundance of life and the exceeding rapidity with which all living beings multiply. Whether animal or plant, large or small, powerful or puny, every species multiplies according to the laws of geometrical progression, each with a ratio of its own. The effect of this fact upon mere numbers is a point not easily comprehended. The fastest-multiplying forms are the bacteria, some species of which are able, under good conditions, to double every twenty minutes. At this rate a single individual with its descendants would, if uninterrupted, fill all the oceans of the earth in an incredibly short space of time. A single ear of corn of good size has one thousand kernels, and an average ear has, say, six hundred, each capable of reproducing a similar ear. How long would it take at this rate for the product ...