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Hudson, W. H. (William Henry), 1841-1922

"The Naturalist in La Plata"

It is not, however, only on these great
occasions, when the end is sought by unusual means, that spiders show
their intelligence; for even these things might be considered by some as
merely parts of one great complex instinct; but at all times, in all
things, the observer who watches them closely cannot fail to be
convinced that they possess a guiding principle which is not mere
instinct. What the stick or stone was to primitive man, when he had made
the discovery that by holding it in his hand he greatly increased the
force of his blow, the possession of a web has been to the spider in
developing that spark of intellect which it possesses in common with all
animal organisms.


CHAPTER XV.
THE DEATH-FEIGNING INSTINCT.

Most people are familiar with the phenomenon of "death-feigning,"
commonly seen in coleopterous insects, and in many spiders. This highly
curious instinct is also possessed by some vertebrates. In insects it is
probably due to temporary paralysis occasioned by sudden concussion, for
when beetles alight abruptly, though voluntarily, they assume that
appearance of death, which lasts for a few moments. Some species,
indeed, are so highly sensitive that the slightest touch, or even a
sudden menace, will instantly throw them into this motionless,
death-simulating condition. Curiously enough, the same causes which
produce this trance in slow-moving species, like those of Scarabseus for
example, have a precisely contrary effect on species endowed with great
activity.


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