A Spider's Life
Thousands of species of spiders exist. Each is unique, but spider lives
do follow certain patterns:
- Like Charlotte in CHARLOTTE'S WEB, many spiders die in autumn after
producing an egg sac. But some adults live through the winter, mate
in the spring, and then die, and some survive for two or more years.
Large wolf spiders may live for several years, and tarantulas have
lived as long as 20 years.
- Most baby spiders hatch when the weather gets warm, but a few hatch
from their eggs during fall or winter. It's hard to notice that they've
hatched, though, because they stay quietly inside the egg sac until
The first thing most kinds of spiderlings do after emerging
from the egg sac is to spin a dragline and balloon away.
spiderlings are still very tiny, they climb to a
or other tall
object and tilt their spinnerets up into the
air. The breeze pulls silk threads out of the
spinnerets. These threads form a "dragline." The
spider is still very tiny and light. When the
thread gets long enough, the wind suddenly
plucks it up, along with the spiderling at
the other end, and carries them away! This
works because the spiderling is so light and
its dragline long enough to give them a lot
of surface area for their weight.
The average female spider's egg sac holds
about 100 eggs, but some large spiders can
produce a sac that holds 2,000 eggs.
Some mothers protect their egg sac until
the spiderlings emerge. Some spiders attach
the sac to a web, or to a plant or other structure.
Some carry the egg sac wherever they go on
their abdomen, and some even drag it behind
them, attached to their spinnerets! (Charlotte
is quite likely the only spider known to have
entrusted her egg sac to a pig.)
While they are growing, baby spiders molt,
or shed their skin, several times. The new,
larger skin is very soft when the old skin
falls off, but quickly dries and hardens to
provide protection. The bigger a spider grows,
the more times it must molt. Tarantulas must
molt more than 20 times before they're fully
food, but each
kind of spider
food in its