World's oldest spider web found on English beach
The world's oldest spider web, spun when dinosaurs still roamed the 
Earth, has been discovered in a piece of amber from a beach in the 
south of Britain.
 
By Richard Gray, Science Correspondent 
Last Updated: 4:02PM GMT 13 Dec 2008
Scientists working at Oxford University found tiny threads of spider 
silk encased inside a piece of amber that formed around 140 million 
years ago.
The web appears to be similar to those of modern orb web spiders, 
which weave a spiral web of silk to catch insect prey.
The discovery suggests that orb web spinning spiders existed far 
earlier than had been previously thought, at a time before flowering 
plants appeared on the planet and triggered an explosion in flying 
insects.
The scientists believe the web became trapped in conifer resin in the 
aftermath of a forest fire and then became fossilised inside the 
resulting amber.
They hope that by studying other pieces of amber from the same 
deposits they may learn more about spiders from that time and the prey 
they ate.
Professor Martin Brasier, a palaeobiologist at Oxford University who 
led the study, said: "It is absolutely consistent with an orb web 
spider. The spacing between the threads suggest they were the 
structural struts onto which a web was spun.
"The treads themselves are made of two pieces joined together just 
like a modern web. The spider spins the threads from two spinnerets at 
its back and twirls them together. The amber flow appears to have cut 
across the web and embalmed it.
"We have also found a few tangles of web in the amber. It is amazing 
to see something so delicate that has survived so many million years."
The amber was found on a beach famous for fossilised dinosaur tracks 
near Bexhill, in East Sussex, by amateur fossil hunter Jamie Hiscocks.
He took the amber to Professor Brasier and his student Laura Cotton, 
who will reveal their findings at the annual meeting of the 
Palaeontological Association in Glasgow this week.
Using advanced microscope techniques, the scientists were able to peer 
into the amber to build up a picture of what was inside.
By merging 40 image slices taken through the amber, they discovered 
threads of spider web each more than a millimetre in length.
Pieces of charred bark and burnt sap inside the amber suggest the 
trees that produced the fossilised resin had been damaged in a fire 
and produced the droplets of resin to protect itself from infection.
Fossilised charcoal was also found in the fossil beds near to the 
amber along with fossilised tracks of Iguanodon, large plant eating 
dinosaurs.
Until now the oldest known spider web was found in 130-million-year-
old amber discovered in Lebanon and the earliest fossilised orb spider 
was found in a fragment of amber 120-million-years-old.
This latest discovery proves that the web-spinning arachnids were 
around millions of years earlier still. Delicate structures like 
spider webs are not normally fossilised and can only be preserved if 
they have been caught up in resin such as amber.
Professor Brasier said: "The amber appears to have been flowing 
through lower parts of the trees near to the ground so we can imagine 
little cobwebs forming in the very lower parts of the tree trunk.
"Webs are used to catch things flying through the air and we know that 
all sorts of insect groups were starting to become quite adept at 
flying at this time. Many of the modern fly group, mosquitoes, bees 
and wasps all take off at this time.
"These webs were around in a conifer dominated world before flowering 
plants, but it is clear it was already gearing up for the huge 
diversity of flowers brought with them. The spiders appeared to be 
keeping up with the other evolutionary patterns in the insects."
Ancient amber deposits more than 100-million-year-old are extremely 
rare and scientists hope the Bexhill amber will reveal yet more 
secrets. The amber deposit, which is hidden beneath the tide for much 
of the time, is also believed to be the first significant amber 
deposit in Britain. Most famous amber deposits have been found in 
France, Germany, the Caribbean and Lebanon.
Amber deposits, which form from fossilised tree resin, have attracted 
intense public attention in the wake of the hit film Jurassic Park 
where scientists used dinosaur blood extracted from mosquitoes 
preserved in amber to clone dinosaurs.
Dr Samuel Zschokke, an expert in ancient spider webs at Basel 
University, Switzerland, who discovered the 130-million-year-old 
spider web in Lebanese amber, said: "This sounds rather exciting. It 
appears that a new record has been set.
"Spider silk probably evolved back in the Devonian period and it has 
probably been used to build webs for some 200 million years. The 
limiting factor for the oldest fossil spider silk is not the 
occurrence of silk at these early times but the existence of fossil 
bearing amber."
http://www.telegraph.co.uk/scienceandtechnology/3741617/Worlds-oldest-
spider-web-found-on-English-beach.html


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