Quotes from Charles Darwin

Why is The Origin of Species such a great book? First of all, because it convincingly demonstrates the fact of evolution: it provides a vast and well-chosen body of evidence showing that existing animals and plants cannot have been separately created in their present forms, but must have evolved from earlier forms by slow transformation.

We here see in two distant countries a similar relation between plants and insects of the same families, though the species of both are different. When man is the agent in introducing into a country a new species this relation is often broken:

biraz aptal olan kimseler, her ÅŸeyi göreneÄŸe göre ya da al??kanl?kla yapmaya eÄŸilimlidirler; ve böyle davranmaya yüreklendirilirlerse daha çok mutlu olurlar.

In the latter country alone, very many (probably several hundred) square miles are covered by one mass of these prickly plants, and are impenetrable by man or beast. Over the undulating plains, where these great beds occur, nothing else can now live. Before their introduction, however, the surface must have supported, as in other parts, a rank herbage. I doubt whether any case is on record of an invasion on so grand a scale of one plant over the aborigines.

It was evident that such facts as these, as well as many others, could only be explained on the supposition that species gradually become modified; and the subject haunted me.

Pueden los instintos adquirirse y modificarse por medio de la selección natural? ¿Qué diremos del instinto que lleva a la abeja a hacer celdas, y que prácticamente se ha adelantado a los descubrimientos de notables matemáticos?

None can reply - all seems eternal now. The wilderness has a mysterious tongue, which teaches awful doubt.

Dos animales caninos, en tiempo de hambre, luchan mutuamente por conseguir el alimento que necesitan; pero la planta que nace en los linderos del desierto lucha por la existencia contra la sequía, aunque con más propiedad se diría que depende de la humedad.

This prophecy has turned out entirely and miserably wrong.

El embrión no queda afectado, y sirve como indicio de la pasada condición de las especies. Por eso sucede que las especies existentes, durante los primeros períodos de su desarrollo, se parecen a menudo a formas antiguas y extinguidas

El muérdago depende del manzano y de otros pocos árboles, pero solamente en sentido muy artificial puede decirse que lucha con estos árboles, porque si en el mismo árbol crecen muchos de estos parásitos, el árbol languidece y muere. Pero de algunos muérdagos que producen semillas y que crecen juntamente en la misma rama puede decirse con más razón

The truth is something you must find out for yourself. It is like a voyage of discovery and you will meet many adventures along the way. Listen to people's opinions but in the end it must be for you to determine truth as you find it. Charles Darwin (1809 - 1882)

A man's friendships are one of the best measures of his worth

La belleza, en muchos casos, parece ser debida por completo a la simetría del crecimiento. Las flores se clasifican entre las producciones más hermosas de la naturaleza; pero se han hecho visibles por contraste con las hojas verdes, y por consiguiente hermosas, al mismo tiempo para que puedan ser fácilmente observadas por los insectos.

Todo ser que durante el tiempo natural de su vida produce varios huevos o semillas, necesita sufrir destrucción durante algún período de su vida y durante alguna estación o en alguno que otro año, porque de otro modo, por el principio del aumento geométrico llegaría pronto su número a ser tan desordenadamente grande, que no habría país capaz de soportarlo.

We shall best understand the probable course of natural selection by taking the case of a country undergoing some slight physical change, for instance, of climate. The proportional numbers of its inhabitants will almost immediately undergo a change, and some species will probably become extinct.

I was much struck how entirely vague and arbitrary is the distinction between species and varieties. ... But to discuss whether they are rightly called species or varieties, before any definition of these terms has been generally accepted, is vainly to beat the air.

Further on, he adds, that dogs, when feeling affectionate, lower their ears in order to exclude all sounds, so that their whole attention may be concentrated on the caresses of their master! Dogs have another and striking way of exhibiting their affection, namely, by licking the hands or faces of their masters.

it is so important to bear in mind the probability of conversion from one function to another

modern geology has almost banished such views as the excavation of a great valley by a single diluvial wave, so will natural selection, if it be a true principle, banish the belief of the continued creation of new organic beings, or of any great and sudden modification in their structure.

What natural selection cannot do, is to modify the structure of one species, without giving it any advantage, for the good of another species; and though statements to this effect may be found in works of natural history, I cannot find one case which will bear investigation.

las variaciones y diferencias individuales favorables, y la destrucción de aquellas que son nocivas, es lo que hemos llamado selección natural o supervivencia de los más aptos.

Slow though the process of selection may be, if feeble man can do much by his power of artificial selection, I can see no limit to the amount of change to the beauty and infinite complexity of the coadaptations between all organic beings, one with another and with their physical conditions of life, which may be effected in the long course of time by nature's power of selection.

But with regard to the material world, we can at least go so far as this—we can perceive that events are brought about not by insulated interpositions of Divine power, exerted in each particular case, but by the establishment of general laws.