Saturday, August 24, 2013

Spiders

In Fact , I don’t really like spiders. I’m actually terrified of them. For that reason I really like collecting them. Not real ones mind you, but figurines, pictures etc. Spiders are very beautiful creatures, I’m just not a fan of their ability to bite and possibly poison me. Figurines can’t hurt you unless you break them and then you can get a nasty cut. I know that part from experience , but I like to know about spiders and read more about them , So Let us Know More Species :)

Glass Spider



Egyptian Giant Solpugid (Camel Spider)

these arachnids are not half the size of a full-grown man. They are big though, reaching about 6 six inches (15 centimeters) in length.
Camel spiders became an Internet sensation during the Iraq war of 2003, when rumors of their bloodthirsty nature began to circulate online. Many tales were accompanied with photos purporting to show spiders half the size of a human.
For many years, Middle Eastern rumors have painted camel spiders as large, venomous predators, as fast as a running human, with a voracious appetite for large mammals. The myths are untrue. These creatures do not actually eat camels' stomachs or sleeping soldiers, and they are not so large—but the real camel spider is still an amazing predator.
The camel spider's history of misinformation begins with a misidentification. Camel spiders are not even spiders. Like spiders, they are members of the class Arachnida, but they are actually solpugids.
Camel spiders, also called wind scorpions and Egyptian giant solpugids (SAHL-pyoo-jids), are only about 6 inches (15 centimeters) long. Photos that purport to show creatures six times that size have misleading perspective—the spider is invariably placed in the foreground where the lens makes it appear much bigger than its actual size. True, they are fast, but only compared to other arachnids. Their top speed is estimated at 10 miles (16 kilometers) per hour.
Camel spiders are not deadly to humans (though their bite is painful), but they are vicious predators that can visit death upon insects, rodents, lizards, and small birds. These hardy desert dwellers boast large, powerful jaws, which can be up to one-third of their body length. They use them to seize their victims and turn them to pulp with a chopping or sawing motion. Camel spiders are not venomous, but they do utilize digestive fluids to liquefy their victims' flesh, making it easy to suck the remains into their stomachs.


Black Widow Spider

Notorious for their bloodthirsty courtship, black widow spiders are identified by the colored markings on their black bodies.
Black widows are notorious spiders identified by the colored, hourglass-shaped mark on their abdomens. Several species answer to the name, and they are found in temperate regions around the world.
This spider's bite is much feared because its venom is reported to be 15 times stronger than a rattlesnake's. In humans, bites produce muscle aches, nausea, and a paralysis of the diaphragm that can make breathing difficult; however, contrary to popular belief, most people who are bitten suffer no serious damage—let alone death. But bites can be fatal—usually to small children, the elderly, or the infirm. Fortunately, fatalities are fairly rare; the spiders are nonaggressive and bite only in self-defense, such as when someone accidentally sits on them.
The animals most at risk from the black widow's bite are insects—and male black widow spiders. Females sometimes kill and eat their counterparts after mating in a macabre behavior that gave the insect its name. Black widows are solitary year-round except during this violent mating ritual.
These spiders spin large webs in which females suspend a cocoon with hundreds of eggs. Spiderlings disperse soon after they leave their eggs, but the web remains. Black widow spiders also use their webs to ensnare their prey, which consists of flies, mosquitoes, grasshoppers, beetles, and caterpillars. Black widows are comb-footed spiders, which means they have bristles on their hind legs that they use to cover their prey with silk once it has been trapped.
To feed, black widows puncture their insect prey with their fangs and administer digestive enzymes to the corpses. By using these enzymes, and their gnashing fangs, the spiders liquefy their prey's bodies and suck up the resulting fluid.


Floral Spider

Crab Spider inside a flower.


Biggest Fossil Spider Found

The biggest known fossil spider has been found in China, a new study says.
Measuring nearly 1 inch (2.5 centimeters) in length, the 165-million-year-old fossil was uncovered in 2005 by farmers in Inner Mongolia —a region teeming with fossils from the middle Jurassic Period .
"Compared to all other spider fossils, this one is huge," said study co-author ChungKun Shih, a visiting professor at Capital Normal University in Beijing, China.
"When I first saw it, I immediately realized that it was very unique not only because of its size, but also because the preservation was excellent," Shih said.
Fine volcanic ash preserved the specimen's exquisite features, such as mouthparts and hairlike structures that covered its legs, according to the study.
These features allowed scientists to classify it as Nephila jurassica, a new species in the genus Nephila—a surviving group of spiders that weave 5-foot (1.5-meter) webs of strong, golden silk. Among the largest web-weaving spiders today, these creatures can reach lengths of up to 2 inches (5 centimeters).
Biggest Fossil Spider Drove Insect Evolution?
The fossil spider shows that Nephila is the spider genus that's been around the longest. The rare discovery pushes back the origin of the genus by about 130 million years. 
Because modern-day Nephila spiders thrive in tropical and subtropical habitats, the discovery also provides evidence that northeastern China was warmer and more humid during the Jurassic than it is now.



Small Spiders Have Big Brains That Spill Into Their Legs

Rachel Kaufman
They're not fat, they're just big-brained: Tiny spiders have such hugebrains for their body sizes that the organs can spill into the animals' body cavities, a new study shows.
Such big brains may explain why very small spiders—some less than a millimeter across—are just as good at spinning webs as bigger arachnids.

For the study, a team led by Bill Eberhard , a staff scientist at the Smithsonian Tropical Research Institute and a professor at the University of Costa Rica, examined nine spider species from six web-weaving families.
The researchers found that the smaller the spider, the bigger its brain relative to its body size.
In some spiders, the central nervous system took up nearly 80 percent of the space in their bodies, sometimes even spilling into their legs.
And the brain-filled bodies of some baby spiders—such as the young of the orb-weaver Leucauge mariana—bulge until the spiders grow to adult size.
Spider Burglars Are Brainy, Too
Taking up so much body space for a brain would seem to be a problem for a spider's other organs, Eberhard said. "But [that aspect] hasn't really been studied."
Just by the way the spiders look, though, it would make sense that the arachnids are trading something for their big brains.
For instance, in the jumping spider Phidippus clarus, which the researchers examined in a separate study, the adult's digestive system is in the spider's cephalothorax—its head and body cavity.
But "in the young one, all that stuff is filled up with brain," and the baby spider has a less developed digestive system. It's still unclear, though, what impact this has on the developing spiders.
Presumably, large brains are necessary to spin webs, a behavior thought to be more complex that, say, "a larval beetle that simply eats its way through the fungus where it lives," Eberhard wrote in an article describing the research.
Still, three so-called kleptoparasitic spiders—which have lost the ability to spin webs and instead steal prey from other spiders—had "no signs of having a relatively smaller brain," he said.
Of course, he added, being sneaky and stealthy also requires a certain level of smarts, which may explain why spider burglars seem to be just as brainy as their web-weaving counterparts.

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