Spiders

The spiders section begins with a gallery covering different types of spiders native to North America. Most of the spiders belong to the orbweaver family, (Araneidae) and they are commonly found in residential areas, and subsequently in homes across North America.


What Do Spiders Eat?

Spiders, long considered carnivores, (although there might be exceptions to that rule), traditionally choose insects and other arachnids as their primary source of food.

Arachnologists, scientists who study spiders, have long been intrigued by spider diets. One question they consider, "Are Spiders Picky Eaters", has been the subject of both observation and scientific experimentation.

Like all scientists, when arachnologists conduct experiments on spider diets, they are trying to stay as objective as possible with respect to the potential answers.

Objectivity in scientific experimentation often loosely translates into scientists trying to prove their thinking is wrong, rather than prove their thinking is correct. Scientifically, the process is known as testing the null hypothesis.

A pair of arachnologists conducting experiments on the pickiness of spider eating habits, started with the hypothesis that spiders eat any insects that come their way.

They conducted an experiment with an Araneidae species, an orb weaving spider (Micrathena Gracilis).

Over an extended period of time, they counted the number and size of insects that flew into the web. They also recorded the number and size of the insects that the spider captured for dinner.

Testing the null hypothesis meant that the researchers thought that the spider would eat all the insects that landed in the web, regardless of insect size.

At the end of their experiment, they concluded that when given the choice between large and small insects caught in the web, the spider preferred larger insects.

In scientific terms, they concluded there was a statistically significant relationship between spider diet and insect size. The hypothesis that spiders are picky eaters still stands.

Types of Spider Webs

Spiders can be either hunters or gatherers, with webs serving as the primary hunting tool for gathering spiders.

All spider webs are made from silk, produced by an organ called spinnerets, which are located on the spider's abdomen.

All spiders, including the hunters, use silk for one reason or another.

Jumping spiders, for example, although formally classified as hunting spiders, use silk as a type of bungee cord for added protection as they literally jump from leaf to leaf or branch to branch in search of prey.

Because of their specialized hunting method, web building spiders typically have a larger number of silk glands than hunting spiders.

Spiders are often further classified according to the types of webs they build.

Three of the better known groups of spiders that build different types of webs are the orb weavers, cobweb spiders and funnel weavers. The picture on the left shows a basic orb web.

Many common garden spiders, such as the writing spider, are orb weavers.

Cobweb spiders belong to the family Theridiidae. They make their multidimensional webs in many homes and gardens. Most references you read on the internet also point out that black widow spiders (redback spiders in Australia) belong to this family.

Funnel web spiders (family Agelenidae) also go by the name grass spiders because their webs are commonly found at ground level. Like cobweb spiders, their webs are multidimensional, with the added feature of a built in funnel shaped hole. It serves as protection as the spider waits to catch prey.

There are close to one hundred different species of funnel web spiders in the United States.

Spider Quiz

Each of the following five questions comes accompanied by a spider picture. Click on the circle next to your answer for each question. When you are finshed, click on the results button to see your score.



1. This spider might feel as comfortable in school as it feels in its web catcing insects.

a. Writing Spider
b. Spelling Spider
c. Praying Spider
d. Reading Spider
e. Arithmetic Spider

2. Many species of these spiders have colorful bodies.

a. Running Crab Spider
b. Crab Spider
c. Fishing Spider
d. Jumping Spider
e. Walking Spider

3. This tiny spider is almost an acrobat.

a. Deer Spider
b. Horse Spider
c. House Spider
d. Jumping Spider
e. Walking Spider

4. This spider is well known for carrying its egg sac under its abdomen.

a. Cat Spider
b. Spiderman
c. Queen Spider
d. Royal Spider
e. Wolf Spider

5. Water areas are popular with this spider.

a. Crab Spider
b. Fishing Spider
c. Swimming Spider
d. Walking Spider
e. Web Spider



© 2001-2014 Patricia A. Michaels