6 Interesting Facts About SpidersDr. Jim Fredericks
Tuesday, August 12, 2014
Fun facts that may or may not make spiders seem less
Spiders have adapted to live in nearly every
type of habitat, and they are one of the top 10 most diverse
populations on earth. They play vital roles in all ecosystems
-except in your home.
The following spider facts will help you learn more about these
eight-legged pests, some of which might appear in your backyard
this summer and fall.
All spiders produce silk
Something common to all 40,000 species of spiders is that they
all spin silk. And as spiders have evolved, so has their ability to
work with silk. One spider can produce up to seven different types,
each used for a different purpose such as spinning webs or
One species is mostly vegetarian
It was thought that all spiders were carnivorous, capturing and
eating other insects, but one species in Central America has been
found to be mostly herbivorous!
Bagheera kiplingi inhabit trees that produce protein-rich buds
on their leaves. These buds are part of a symbiotic relationship
between the trees and ants, but B. kiplingi also benefit from
consuming the buds. However, during dry seasons these spiders are
known to be carnivorous. They may cannibalize each other or steal
ant larvae when food is scarce.
Spiders are nearsighted
Most spiders have eight eyes, but some, like the brown recluse
spider, only have six. Spiders typically have a main set that can
create images while the secondary sets can only detect light and
shadow. It is thought that the secondary sets of eyes are derived
from the compound eyes of a common ancestor to both spiders and
But even with all of those eyes, spiders cannot see far into the
distance. Nearsightedness is a problem for people, but the habits
of spiders are such that being nearsighted isn't a deficiency. They
wait for prey to get caught in their webs and use silk trip wires
to warn of approaching predators.
Females can lay up to 3,000 eggs at one time
These eggs are housed in one or more silk sacs. The level of
care a female spider provides for her young varies by species. Some
females will die shortly after laying eggs while others will carry
spiderlings on their backs or share prey with them.
Jumping spiders can jump up to 50x their own length
When hunting or trying to escape a predator, jumping spiders are
able to make very agile movements and jump multiple times their
body length. This is possible due to an internal hydraulic system.
Jumping spiders can alter the pressure of fluids in their legs
resulting in a springing motion that propels the spiders
The 'daddy long-legs' you see might not actually be a
The nickname 'daddy long-legs' has been given to several
different pests, only one of which is an actual spider. Crane
flies, harvestmen and cellar
spiders are all colloquially identified as 'daddy long-legs.'
Only cellar spiders are spiders. Harvestmen are in the arachnid
family, but they lack venom and silk glands. Crane flies are
agricultural pests with very long legs and the ability to fly.
If you think you have a spider infestation in your home, contact a licensed
pest professional to identify the species and recommend steps for
removal or treatment. Some species are poisonous
to humans and should be handled by a professional.
To learn more about the different types of spiders found in the
United States, read our Spiders 101 article.