Read each of the passage below, and then answer the questions that follow the passage. The correct response may be stated outright or merely suggested in the passage.
The following passage is taken from a classic study of tarantulas published in scientific America in 1952.
A fertilized female tarantula lays from 200 to 400
eggs at a time, thus it is possible for a single
tarantula to produce several thousand young. She
takes no care of them beyond (5) weaving a cocoon
of silk to enclose the eggs. After they hatch, the
young walk away, find convenient places in which
to dig their bur-rows and spend the rest of their
lives in sole-tude. Tarantulas feed mostly on insects
and (10) millipeds. Once their appetite is appeased,
they digest the food for several days before eating
again. Their sight is poor, being limited to sensing a
change in the intensity of light and to the perception
of moving objects. They (15) apparently have little
or no sense of hearing, for a hungry tarantula will
pay no attention to a loudly chirping cricket placed
in its cage unless the insect happens to touch one of
its legs. (20) but all spiders, and especially hairy
ones, have an extremely delicate sense of touch.
Laboratory experiments prove that tarantulas can
distinguish three types of touch: pressure against
the body wall, stroking of the body (25) hari and
riffling of certain very fine hairs on the legs called
trichobothria. Pressure against the body, by a finger
or the end of a pencil, causes the tarantula to move
off slowly for a short distance. The touch (30)
response unless the approach is from above, where
the spider can see the motion, in which cases it rises
on its hind legs, lifts its front legs, opens its fangs
and holds this threatening pos-ture as long as the
object continues to move. (35) when the motion
stops, the spider drops back to the ground, remains
quiet for a few sec- onds, and then moves slowly
away.
The entire body of a tarantula, especially its legs, is
thickly clothed with hair. Some of it (40) is short
and woolly, some long and stiff. Touching this
body hair produces one of two distinct reactions.
When the spider is hungry, it responds with an
immediate and swift attack. At the touch of a
cricket’s antennae the (45) tarantula seizes the
insect so swiftly that a motion picture taken at the
rate of 64 frames per second shows only the result
and not the process of capture. But when the spider
in not hungry, the stimulation of its hairs merely
(50) causes it to shake the touched lim. An insect
can walk under its hairy belly unharmed the
trichobothria, very fine hairs growing from disk like
membranes on the legs, were once thought to be the
spider’s hearing organs, (55) but we now know that
they have nothing to do with soon they are sensitive
only to air movement. A light breeze makes them
vibrate slowly without disturbing the common hair.
When one blows gently on the trichobothria, (60)
the tarantula reacts with a quick jerk of its four
front legs. If the front and hind legs are stimu-lated
at the same time, the spider makes a sud-den jump.
This reaction is quite independent of the state of its
appetite. (65) these three tactile responses – to
pressure on the body wall, to moving of the
common hair, and to flexing of the trichobothria-are
so different from one another that there is no
possibility of confusing them. They serve the (70)
tarantula adequately for most of its needs and
enable it to avoid most annoyances and dangers.
But they fail the spider completely when it meets its
deadly enemy, the digger wasp Pepsis.
Sub-Questions
The passage details the life cycle, feeding habits, and sensory capabilities of tarantulas, noting their high fertility but minimal maternal care. It explains how tarantulas rely heavily on a sensitive sense of touch—distinguishing pressure, body hair stimulation, and air movement via specialized hairs—to interact with their environment and capture prey. Despite these effective adaptations for survival, the passage concludes that tarantulas are defenseless against their natural predator, the digger wasp Pepsis.
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