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First crosses between forms known to be varieties, or sufficiently alike to be considered as varieties, and their mongrel offspring, are very generally, but not, as is so often stated, invariably fertile. Nor is this almost universal and perfect fertility surprising, when it is remembered how liable we are to argue in a circle with respect to varieties in a state of nature; and when we remember that the greater number of varieties have been produced under domestication by the selection of mere external differences, and that they have not been long exposed to uniform conditions of life. It should also be especially kept in mind, that long-continued domestication tends to eliminate sterility, and is therefore little likely to induce this same quality.

Explanation and Analysis:

In this quote from near the end of the chapter, Darwin once again returns to the theme of the distinction between varieties and species. Here, he notes that one of the key features of varieties is that, despite their differences, their offsprin...

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Original

Romeo

(aside) She speaks.
O, speak again, bright angel! For thou art
As glorious to this night, being o’er my head,
As is a winged messenger of heaven
Unto the white, upturnèd, wondering eyes
Of mortals that fall back to gaze on him
When he bestrides the lazy-puffing clouds
And sails upon the bosom of the air.

Juliet

O Romeo, Romeo! Wherefore art though Romeo?
Deny they father and refuse they name.
Or, if thou wilt not, be but sworn my love,
And I’ll no longer be a Capulet.

Modern

Romeo

(to himself) She speaks. Speak again, bright angel! For tonight you are as glorious, there up above me, as a winged messenger of heaven who makes mortals fall onto their backs to gaze up with awestruck eyes as he strides across the lazy clouds and sails through the air.

Juliet

O Romeo, Romeo! Why must you be Romeo? Deny your father and give up your name. Or, if you won’t change your name, just swear your love to me and I’ll give up being a Capulet.

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