Alfred Victor Espinas

“ He remarks that the living beings of the environment are the preponderant part of the medium for each species. Adaptations not less close than those which unite organisms to the physical medium, put organisms in dependence, one upon another, and provoke morphological variations which wholly change the aspect of each one of them. ”

“ Whatever emotion the application of the doctrine of evolution to the moral world may cause, and however grave may be the shock it inflicts on the edifice of beliefs, it should be accepted with confidence, for it is true, and the truth can not be wrong. ”

“ It is imperatively necessary for us to fix our eyes on this capital point, and to decide among ourselves whether those who in their researches accord a part to final causes, and attribute an exceptional position in nature to man, are performing a work of science or of metaphysics. ”

“ Every type, we may say, is thus formed by these conditions. To them must be attributed not only the variations in detail which only are commonly called adaptations, but the essential traits of the type, "due also to an anterior adaptation, the effects of which have been transmitted from more or less remote ancestors to their posterity." ”

“ The natural sciences thus impose themselves on the attention even of the statesman." It is necessary attentively to follow their progress, to measure the bearing of their discoveries, to study their actual or possible influence on current beliefs and ideas, and to endeavor to construct a new edifice all the more quickly as the bases of the old one appear to be seriously threatened. ”

“ Each of them appeared to be a distinct entity, owing nothing except to itself, capable of abstracting itself from every modifying action on the part of external agents, created once for all in view of certain conditions of existence, marvelously adapted to these conditions, but unable to extricate itself from them except at the cost of perishing, in perfect equilibrium with the supposed unchangeable medium, but destined to disappear whenever the equilibrium was broken. ”

“ The teeth of mammals tell what their regimen is. All their structure is likewise derived and by a kind of reaction from it. "The tongue of the ant-bear and its enormous salivary glands can evidently be useful only for the capture of ants, termites, and other insects living in societies. ”

“ At this point is given a brilliant picture, in which, reviewing the great divisions of the animal kingdom, the author designates in each of the dominant forms of living beings the effect of the conditions of their existence. ”

“ There are insects that never come out of the anthills; some of them are blind, and others can not eat anything but the food with which the ants gorge them." Innumerable parasites have been modified in a similar manner by the animal environment accidentally chosen by them ”

“ Must man be excepted from the general operation of these laws? In no way. It is from the natural sciences thus renovated that we must demand, says M. Perrier, "an exact and scientific notion of the place of man in nature. ”