Spiders aren't the most appealing creatures, but they do serve their purpose ecologically. As frightening as they might be to most people, spiders are fascinating creatures to learn about.
History
• Spiders have existed for at least 350,000 years. There are approximately 37,000 species of spiders in the world.
Function
• Spiders play an important role in the environment by consuming insects. As a group, spiders eat more insects than birds.
Features
• Spiders are not actually considered to be insects. They are arthropods. Spiders have two main body parts consisting of a combined head, thorax--called the cephalothorax--and the abdomen. The spider has no internal skeleton. The body is covered with a hard outer covering called the exoskeleton.
Identification
• Spiders have four pairs of legs. Most spiders have 8 eyes but some have less. The Brown Recluse spider has 6 eyes.
Significance
• All spiders are carnivorous predators. Most are nocturnal hunters. Spiders can survive for several weeks without food. The Brown Recluse spider has a violin shape on the upper side of the cephalothorax. The Black Widow has two reddish markings that join to form an hourglass shape.see more at what do spiders eat.
