The first definite spiders, thin-waisted arachnids with abdominal segmentation and silk producing spinnerets, are known from fossils like Attercopus fimbriungus. This spider lived 380 million years ago during the Devonian Period, more than 150 million years before the dinosaurs.
As if dinosaurs weren't enough to contend with in the world of 165 million years ago, the Jursassic period had other frightful creatures roaming the Earth as well: giant spiders. In fact, a Kansas University researcher recently identified the largest known fossilized spider, a relic of the Middle Jurassic period.
Spiders as a group date back to more than 300 million years ago.
In 1980 paleontologist Mario Hunicken made a startling announcement; he had found the remains of the largest spider to have ever lived. Discovered in the approximately 300 million year old rock of Argentina, this prehistoric arachnid appeared to have a body over a foot in length and a leg span of over 19 inches.
The researchers tell the journal Biology Letters that Nephila jurassica, as they have called their specimen, would have had a leg span of some 15cm. "She is the largest known fossil spider," said Professor Paul Selden from the University of Kansas, US.
The world's largest known spider is a male goliath bird-eating spider (Theraphosa blondi) collected by members of the Pablo San Martin Expedition at Rio Cavro, Venezuela in April 1965. It had a record leg-span of 28 cm (11 in) - sufficient to cover a dinner plate.
The Goliath Birdeater (Theraphosa blondi) belongs to the Tarantula family and, weighing in at up to six ounces, is the most massive spider in the world. It can grow to be up to 11 inches in diameter, has a fist-sized body, and is second in leg length only to the spindly Great Huntsman. Females can live up to 20 years.
So unless they did a complete overhaul of their respiratory system, a giant spider wouldn't be able to get enough oxygen to move around. This could be related to why some giant dragonflies were able to fly around 300 million years ago, when the atmosphere contained more oxygen (35% compared to 21% now).
The creatures were tiny, with a body length of about two-tenths of an inch, including the tail.
Arachnids from all over the world could be at risk of extinction because of the exotic pet trade. Researchers have warned that spiders, scorpions and their relatives are at risk from uncontrolled collecting from the wild, and that some species might go extinct before they are scientifically described.
The vast majority of spiders are harmless and serve a critical purpose: controlling insect populations that could otherwise devastate crops. Without spiders to eat pests harmful to agriculture, it's thought that our food supply would be put at risk.
The arachnid turned out to have had spiderlike mouthparts and legs. But unlike true spiders, it lacked spinnerets. It also had a segmented abdomen, rather than a fused abdomen, which modern spiders have.
“If spiders disappeared, we would face famine,” says Platnick, who studies arachnids at New York's American Museum of Natural History, where a live spider exhibit debuted last month. “Spiders are primary controllers of insects. Without spiders, all of our crops would be consumed by those pests.”
Other than birds, however, there is no scientific evidence that any dinosaurs, such as Tyrannosaurus, Velociraptor, Apatosaurus, Stegosaurus, or Triceratops, are still alive. These, and all other non-avian dinosaurs became extinct at least 65 million years ago at the end of the Cretaceous Period.
For the first time ever, a group of researchers has sequenced the genome of the spider. This knowledge provides a much more qualified basis for studying features of the spider. It also shows that humans share certain genomic similarities with spiders.
Iceland, however, is an island in the lower Arctic or higher Boreal region, where very big spiders are not found naturally. There are 91 species of spider in Iceland—none of which are poisonous to humans— plus the occasional visitor or migrant. This is a small number, compared with 44,000 species known worldwide.
No they don't. Not at least when comparing them to a human nervous systems response to pain. Spiders are a more primitive creature and don't interpret or feel pain in the same way we would think of it.
Unfortunately, due to spiders' territorial and cannibalistic nature, their silk has been impossible to mass produce, so practical applications have yet to materialize.
A large species of tarantula native to the east coast region of Australia, the whistling spider, is the largest spider in the country. As the largest spider in Australia, whistling spiders can grow a leg span of up to 16 cm (6.2 inches) and a body size of around 6 cm (2.3 inches).
But before you rush to permanently enclose yourself in a plastic bubble, remember that—thankfully—spiders don't actually eat humans and instead help keep the world's other creepy crawlers in check.
They do not have venom glands, fangs or any other mechanism for chemically subduing their food. Therefore, they do not have injectable toxins. Some have defensive secretions that might be toxic to small animals if ingested.
In this regard, the biggest spider in the world in terms of its weight is the Goliath Birdeater, while Giant Huntsman Spider is the biggest in terms of its length and appearance. However, the goliath birdeater has become the world's biggest spider due to its massive body size, weight, and leg span.
Discovered in 2001, the giant huntsman spider lives in the caves of Laos. They are known as the giant crab spiders and have a leg span of up to five inches. The giant huntsman spider can grow to be 12 inches across, which is larger than a human head.