Posts tagged: spiders
Bizarre Assassin Spiders Discovered in Madagascar (2006)
by Blake de Pastino
With its fearsome appearance, poisonous bite, and deadly hunting skill, this newly discovered creature lives up to its name: assassin spider.
Researchers working in Madagascar recently discovered this and eight other species of assassin spiders—a family of arachnids that feast on other eight-leggers—during a four-year survey of the island nation’s forests. Assassin spiders have been known to live in Australia and South Africa. But the new find, made by biologists from the California Academy of Sciences in San Francisco, nearly doubles the number of known species.
What’s more, the scientists say these newfound spiders are exquisitely evolved—if grotesque-looking—killers. The spiders stab their prey with their giant jaws, which are barbed at the ends with venomous fangs. To be able to lift their outsized jaws, the assassins evolved elongated necks, giving the spiders a unique ability to strike from a distance.
But arachnophobes can relax: Assassin spiders are a mere 1/8 of an in (2 mm) long and are harmless to humans.
(via: National Geo) (photo: Jeremy Miller/CAS)
MEANWHILE ON PLANET EARTH:
An unexpected side effect of the 2010 flooding in parts of Sindh, Pakistan, was that millions of spiders climbed up into the trees to escape the rising flood waters; because of the scale of the flooding and the fact that the water took so long to recede, many trees became cocooned in spiderwebs. People in the area had never seen this phenomenon before. (Courtesy: National Geographic)
What.
Small Spiders Have Big Brains That Spill Into Their Legs
by Rachel Kaufman
They’re not fat, they’re just big-brained: Tiny spiders have such huge brains 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…
(read more: National Geo)
(photo: female jumping spider Phidippus clarus, by Don Johnston)
Spiders coat their webs with toxins to ward off predators
A tasty spider and its bundle of prey might make an excellent treat for a bunch of marauding ants. So to protect their homes, and themselves, golden orb weavers (Nephila antipodiana) use chemical warfare.
Researchers had long wondered how this species of orb spider — typically found in the ant-rich tropical forests of Singapore, Indonesia, Thailand and the Philippines — manage to avoid becoming dinner.
They found that the spiders coat their webs in a chemical called 2-pyrrolidinone, which acts as a deterrent to many insect species, including ants, moths and caterpillars. The findings appear Nov. 23 in the Proceedings of the Royal Society B.
In an experiment, ants refused to cross lengths of spider silk covered in 2-pyrrolidinone. The researchers suggest this may be because similar chemicals are found in the poison glands of several ant species. The substance could also be triggering a panic response in the ants, which use the same chemical as an alarm pheromone.
Allelopathy (chemical defense) is pretty incredible, and even more so because it came about via natural selection.
oh gosh that is really really cool!!
and look at those legs
whoa!! awesome!
Creepy crawly things (beautifully illustrated). Monographie der Spinnen (Monograph of Spiders 1820-36) by Carl Wilhelm Hahn, German zoologist and illustrator.
(via Spiders are wonderful)
Read this and learn why spiders are so fucking wonderful.
