Spain: web-spinning spider from age of dinosaurs found


Zygiella atrica, a modern descendant of mesozoic spiders

From the BBC:

Early web-spinner found in amber

Spiral orb webs, which to many people typify spiders, were catching insects in their sticky silk while the dinosaurs still walked the Earth.

True orb weaving spiders found trapped in amber from 121-115 million years ago are the oldest of their type yet found.

The spiral webs have proven an extremely successful strategy for catching prey – evidenced by the great diversity of orb weavers present today.

Two specimens are described in the UK Royal Society journal Biology Letters.

The fossil spiders were found embedded in amber from Alava in northern Spain.

They date to the Lower Cretaceous.

Silky skills

Amber is a form of protective resin extruded from trees that has hardened over millions of years.

It is very useful to scientists studying the history of past life because ancient animals and plants are often preserved in the gem-like material.

David Penney of the University of Manchester, UK, and Vicente Ortuno of the University of Alcala, Spain, assign the arachnids to a new species: Mesozygiella dunlopi. …

In Biology Letters, Penney and Ortuno write that spiders may have expanded in number and diversity during the Cretaceous.

An explosion in the abundance of flowering plants begot an expansion of the insects which pollinated them.

These in turn provided prey for the spiders, the authors suggest, which prospered as a result.

There are fossil spiders that date from the Devonian (350-420 million years ago) – long before even the dinosaurs.

In some of these mineral fossils, it is possible to see evidence of spinnerets, the organs spiders use to spin their web silk.

But it is often unclear how fossil spiders used them; some species spin web silk to line their burrows and to protect egg sacs.

See also here.

And here.

According to Dutch daily NRC, there was also fossil spider’s prey in the Mesozoic amber web: a Microphorites fly, a mite, and a Cretevania wasp.

A view very different from this science on the origins of spiders was in Roman mythology: the goddess Minerva turned a weaver woman called Arachne who challenged the gods into a spider.

Spitting spiders in Madagascar: here.

Fossil insects in Amazonia: here.

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4 thoughts on “Spain: web-spinning spider from age of dinosaurs found

  1. Exotic spider with a nasty bite swarms across England – and it’s all thanks to global warming

    04.09.07

    For decades, only the gardens of the South Coast were warm enough for them.

    But after years of mild winters, one of Britain’s most colourful and striking spiders is on the march.

    The population of the wasp spider has exploded and is spreading rapidly north.

    This year, females have been spotted in Surrey and Hertfordshire.

    Wasp spider

    Striped wasp spider’s size in comparision to a two pence coin

    By the end of the autumn – the season when spiders are most in evidence – they could have spread well beyond the Home Counties.

    Wildlife experts urged gardeners yesterday to be on the lookout for the creatures over the next few weeks -and report sightings.

    Originally from the Mediterranean, they were discovered in England in 1922 where the climate was just warm enough for them to survive.

    For decades they clung to the sunnier South Coast but in recent years have been seen as far north as Cambridge.

    Many conservationists believe their move northwards is linked to our warmer climate since the 1970s.

    Stuart Hine, of the National History Museum, said: “We are getting a lot of reports of people finding them in their gardens. Last year we had unprecedented numbers.

    “We are about to start the spider season – when females are at their largest and when the males look for mates – so we could see more.”

    Female wasp spiders are around the size of a 2p piece, with body marking resembling those of wasps and bees.

    But while they can bite, the creatures are not poisonous.

    The males, which are far smaller and brown, are often eaten by the females after mating.

    Because of this danger, males lurk on the edge of the female’s web until

    she sheds her skin.

    For a while after this process her jaws are soft so he can mate in relative safety.

    Despite such precautions, many males are still devoured by their partners.

    The females leave their egg sacs on grass leaves and therefore can only thrive in areas where grass is not regularly grazed or mown.

    The species – Argiope bruennichi – eats beetles, flying insects and grasshoppers.

    Experiments have shown that they are also capable of dealing with the fearsome bombardier beetle.

    The bombardier beetle can produce a blast of hot chemicals from the tip of its abdomen.

    By wrapping the beetle in silk, the spider can immobilise it from a safe distance.

    “They are a prickly, spiny spider so if you pick one up it can feel like you have been bitten,” said Mr Hine.

    “But they are harmless.”

    Hertfordshire’s biological records centre has had four sightings of females in the last year.

    Climate has been linked to the spread of a number alien species across Britain in recent years.

    Among them are scorpions which are reported to have migrated from colonies in London’s docks.

    http://www.thisislondon.co.uk/news/article-23410883-details/Exotic+spider+with+a+nasty+bite+swarms+across+England+-+and+its+all+thanks+to+global+warming/article.do

  2. Think I’ve found 2 in our garden. In Dublin. Is there a view of the underside? Ours looks even more like a wasp from beneath. Stripes are very sharp in contrast.

  3. Pingback: Spectacular spider discovery in London Highgate tombs | Dear Kitty. Some blog

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