Spiders (order Araneae) are air-breathing arthropods that have eight legs and chelicerae with fangs that inject venom. They are the largest order of arachnids and rank seventh in total species diversity among all other orders of organisms.
Anatomy
The anatomy of a spider is very interesting. They are designed to help them move with ease and to conserve energy. Even though there is plenty of variation when you look at the size and colors of spiders they all have general characteristics.
The largest part of the body is the abdomen and it is in varied shapes. Some of the larger spiders look like they have two sections here. This abdominal area is also where the silk is made. They need it to create webs where they will capture their prey.
All spiders have 8 legs and they work as 4 pairs. They are on the sides of the body. With so many legs though they don’t have good balance. They have no muscles in those limbs. Instead, it is hydraulic power that they use for movement.
Many people confuse the spider with an insect. The main difference though is that they don’t have any antenna. They are covered with hair though but it can blend in so well with their coloring that you won’t notice it unless you are very close to the spider.
Their coloring can change too depending on the background where they live. They rely on their colors to help them stay camouflaged from their predators. However, when they have to move out of their normal habitat to find food and shelter they are going to become more vulnerable.
They go through a molting phase when they are adults annually. This allows them to shed their old skin and for new skin to appear in its place. You may find plenty of the dead skin lying around in their habitat too during this time of year.
They have 4 pairs of eyes that help them with direction since they lack in balance. They are also nearsighted so they end up only being able to see what is up close by them. They also have a very advanced central nervous system that allows them to sense danger and to take cover from it. They feature fangs that allows them to inject venom. This venom is typically enough to kill its prey. Depending on the type of spider it may have little effect on humans. With other species though it can make them ill or even kill them. They don’t feature jaws for chewing. Spiders can’t consume solid foods so they have to rely on the venom to cause the prey to start to disintegrate. Then they will suck up all the fluids in order to have their meal. There are touch sensors at the tips of the limbs for the spiders. This helps them to identify surroundings. There are chemical sensors too that help them with taste and smell. It is believed that these sensors also play a role in the process of attracting a mate for many species of spiders.
In most species, the female spiders are much larger than the males. This is something that is very different from most types of living things in the world. In many instances the females are more poisonous and stronger than the males. They may use this to their advantage and kill the males after mating with them.
Many experts do find the anatomy of the spider to be very fascinating. At first glance there may not seem like there is anything unique about it. However, as you look at the minor details you will be able to take a closer look a how all of these fine details really do make a huge difference for the spider.
You can also get a great appreciation for them when you compare various species side by side. You can get a good idea about how their bodies have been transformed to help them thrive in an environment that seems to be constantly changing around them.
Diet and eating habits
They use the venom they inject into prey to help deteriorate it. Then they are able to suck the flesh and the tissues out of it and use that for food. It causes the prey to start to liquefy from the inside out. They will leave the outer shell of their prey behind. This is often going to be a food source for other types of living things out there.
Spiders only use the biting and the venom to make their prey immobile. They use their body to grind up the prey and then they can eat. They will spit the enzymes from deep in their gut area onto the prey. They allow this to sit for a few minutes until it becomes soft enough for them to suck it all up. They have a complex filtering system in place so that solids can’t reach into their gut. This is important so that they are able to avoid digestive problems.
Habitat
Spiders are able to live just about anywhere and that is why there is such diversification out there. They are ranked at #7 when it comes to the most diversified living creatures in the world. That gives you a good idea of the spectrum of how they have branched out. The only place in the world where you won’t find spiders is in Antarctica.
You will be able to find spiders living in very dry climates. Some of them have evolved to the point where they don’t need to be around any water at all. They can survive in some of the harshest conditions you could imagine. They get the water they need from their food sources.
The tropic regions are also home to many species of spiders. Not only are they able to thrive in the climate, they are also able to find plenty of food resources for them to enjoy. These living creatures are known as terrestrial as they almost always live on land. They may be found in trees, on plants, and even living in the blades of grass in your yard.
Spiders are quite versatile and they do well in all types of habitat. They do have to find shelter though when the cooler temperatures settle in. Otherwise their body temperature can change too much and they will die. This is why there are times of the year when you may see them plenty and others that you don’t see them around at all.
It can be tough to fully identify any spider habitat if you aren’t really looking for them. They blend in very well to their natural surroundings. They are able to change colors too if they need to in order to blend in with what is all around them. Not everyone believes that the spider can live in the wetlands but they do.
Some live along the edges of lakes and ponds too. They don’t need the water or the moisture there. Instead, this location offers them a prime area to be able to find lots of food and shelter. It is a winning location for them that helps them to be able to thrive.
Spiders are even making their home in your home. It doesn’t matter how clean you are or how much you look for them. They may be in areas such as crawl spaces, the back of a closet, and even outside in a pile of bricks. If you have lots of clutter in your home though you are offering even more spaces that make an ideal spider habitat.
Many spiders live a much longer life in captivity than they do in the wild. However, it depends on how they are cared for. Some of the larger spiders don’t do well being trapped in a small area. They also become very aggressive if they are touched often due to their heightened senses.
Food supply has a great deal of influence in the spider habitat. This is why you will see some of them in certain areas and not others. They need to be able to build their webs and have enough prey coming along for them to survive. Otherwise they have to look for a new location where those needs can be met.
As humans continue to disrupt the natural habitat of the spiders, they are also branching out in new locations. This is why even dangerous spiders are sometimes seen in places that they never were before. They can get into food shipments and other containers as well. This gives them the chance to find mates and to start to thrive in places that were once vacant of such species.
Spiders as pests
Spiders are among the most prevalent household pests, crawling their way into two out of three American homes. At the same time, the most common creature-based phobia in the world is arachnophobia, the fear of spiders. So when most homeowners spot a spider, they tend to employ the nearest form of DIY pest control, a vacuum or shoe.
But a few fearless folks adopt a live-and-let-live motto, hoping to enjoy some of the good that spiders do. If seeing one dangling in a web or scurrying across the floor doesn’t make you shudder, you might want to share your home with a few spiders.
Be careful, it’s always best to avoid touching a spider. While spiders never actively seek human contact, they will bite if they feel threatened or endangered. Spider venom causes reactions that differ from spider to spider and person to person. Symptoms of a spider bite may include a stinging sensation, red mark, localized swelling or an injury requiring hospitalization. Before you squish the next spider you see, consider how this eight-legged wonder might improve your life.
Spiders are helpful outdoors because they eat many insect pests. Some spiders use webs to catch their prey, others chase and capture it. Most spiders are shy and harmless to humans. Although all spiders have venom, most cannot bite through human skin. However, a few can deliver very painful, poisonous bites, usually when cornered or agitated.
If you want to find out how you can get rid of spiders and keep them away, please check our following articles: How to get rid of Spiders and Prevent infestation with Spiders.
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