Quck answer
Spiders are arachnids that have eight legs and two body parts. They use their silk to create webs, which they use to catch prey. Spiders have specialized body parts, such as spinnerets and fangs, that help them create and consume their webs. They also have a unique respiratory system that allows them to breathe without lungs. Spiders play an important role in controlling insect populations and are fascinating creatures to study.
Wildlife
The Structure of a Spider Web
The photo depicts a female redback spider in her web.
Photo courtesy Steve Clark
An orb-spinning spider is able to create its intricate web by following a preprogrammed instruction manual that is stored in its brain. The process begins with a single thread which serves as the foundation of the web. The spider climbs to a suitable starting point, releases a length of thread into the wind and hopes that the free end will catch onto another branch. If the spider feels that the thread has caught onto something, it cinches up the silk and attaches the thread to the starting point.
The spider walks across the thread, releasing a looser thread below the first one, attaching it on both ends and then climbs to its center. The looser strand sags downward, forming a V-shape. The spider then lowers itself from this point to form a Y-shape which serves as the core support structure of the web.
The spider is able to grip the thin threads with special serrated claws, a smooth hook, and a series of barbed hairs on the end of its legs. It lays more frame threads between various anchor points and starts laying out radius threads from the center of the web to the frames. Since the spider needs to walk across them to get around the web, the frame and radius threads are not coated with sticky material.
After building all the radius threads, the spider lays more non-stick silk to form an auxiliary spiral which extends from the center of the web to the outer edge of the web. The spider spirals in on the web, laying out sticky thread and using the auxiliary spiral as a reference. The spider eats up the auxiliary spiral as it lays out the sticky spiral, resulting in a web with non-sticky radius threads for getting around and a sticky spiral for catching bugs.
The photo shows an Argiope bruennichi orb web spider.
Photo courtesy Ed Nieuwenhuys
The spider sits in the middle of its web monitoring the radius threads for vibrations. When an insect gets caught in any part of the web, the spider feels the motion through the radius threads and makes its way to the vibration source. In this way, the web extends the spider’s sensory system over a much wider area. The spider retreats to a separate nest while monitoring the web via a connected signal line.
Web-spinning spiders are able to distinguish between vibrations from insect prey and vibrations from other sources. Many species can also distinguish the characteristic vibrations of dangerous insects, such as wasps, from their preferred prey.
The photo depicts an orb web spider with wrapped prey.
Photo courtesy Ed Nieuwenhuys
When the orb web has deteriorated and is no longer useful, many spider species destroy it and eat up all the threads so that they can recycle the raw silk material. Spiders may leave the heavy bridge thread so that they can easily rebuild the web at a later point.
Alternative Hunting Methods of Spiders
Spiders have diverse ways to catch their prey besides spinning webs. In the following section, we’ll explore some of these methods.
FAQ
1. What are spiders and what makes them unique?
Spiders are arachnids, which means they are related to scorpions, ticks, and mites. They are unique due to their eight legs, two main body parts, and ability to spin silk. Spiders are also known for their venomous bites and their ability to catch prey in intricate webs.
2. How do spiders spin webs?
Spiders spin their webs using silk that is produced in their abdomen. They have special spinnerets that allow them to control the thickness and shape of the silk as they weave it into intricate patterns. Some spiders also use their silk to create egg sacs or to wrap their prey before eating it.
3. How do spiders catch their prey?
Spiders use their webs to catch prey, but some also actively hunt for food. They have specialized sensory organs that allow them to detect vibrations in the air or on the ground, which helps them locate potential prey. Once they have caught their prey, they will either eat it immediately or wrap it in silk to save for later.
4. What are the different types of spiders?
There are over 45,000 species of spiders, and they come in a wide variety of shapes and sizes. Some common types include orb-weavers, jumping spiders, wolf spiders, and tarantulas. Each type of spider has its own unique characteristics and behaviors.
5. How do spiders reproduce?
Spiders reproduce sexually, with the male depositing sperm into the female’s reproductive system. Females will then lay eggs, which they may protect in an egg sac or attach to a surface. Spiderlings hatch from the eggs and go through several molts before reaching maturity.
6. How do spiders defend themselves?
Spiders have several defense mechanisms to protect themselves from predators. Some species are able to camouflage themselves to blend in with their surroundings, while others are able to jump or run away quickly. They may also use their venomous bites to fend off predators or to subdue prey.
7. Are all spiders venomous?
Not all spiders are venomous, but many are. Venomous spiders use their venom to subdue their prey or to defend themselves from predators. While some spider bites can be dangerous to humans, most are not lethal and can be treated with proper medical care.
8. How long do spiders live?
The lifespan of a spider varies depending on the species. Some may only live for a few months, while others can live for several years. Female spiders tend to live longer than males, as they do not have to expend as much energy on mating.
9. Why are spiders important to the ecosystem?
Spiders play an important role in the ecosystem by controlling insect populations. They are natural predators that help keep other pest populations in check. Additionally, spiders are an important food source for other animals, such as birds and lizards.
Leave a Reply