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The Conditions of Existence as Affecting the Perpetuation of Living Beings

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Language: English
Wordcount: 7,499 / 28 pg
Flesch-Kincaid Reading Ease: 42
LoC Category: B
Downloads: 1,826
mnybks.net#: 3796
Genre: Philosophy
Excerpt

on sexual peculiarities, then all naturalists agree in calling them two species; that is what is meant by the use of the word species--that is to say, it is, for the practical naturalist, a mere question of structural differences.*

[footnote]* I lay stress here on the 'practical' signification of "Species." Whether a physiological test between species exist or not, it is hardly ever applicable by the practical naturalist.

We have seen now--to repeat this point once more, and it is very essential that we should rightly understand it--we have seen that breeds, known to have been derived from a common stock by selection, may be as different in their structure from the original stock as species may be distinct from each other.

But is the like true of the physiological characteristics of animals? Do the physiological differences of varieties amount in degree to those observed between forms which naturalists call distinct species? This is a most important point for us to consider.

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Jeff Gunhus
In an effort to get his very reluctant 11-year old son to get interested in reading Jeff Gunhus wrote his first book, Jack Templar Monster Hunter. Since then, Gunhus has become a bestselling author of thriller and horror novels for adults and the middle grade/YA series, The Templar Chronicles. As our Author of the Day, Gunhus talks about his novel, Killer Pursuit, shares how he juggles writing with being a father of five and reveals why he creates quiet moments in his books.
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