Just put the spider to attack, since it was together with its prey covered with tree sap - and preserved for eternity in amber: Researchers report the first discovery of a spider attack from prehistoric times.
Primal resin has a spider preserved in attacking their prey : In Bernstein researchers have discovered a 100 million year old fossil spider that was about to kill a prisoner in their network wasp.
This is the first fossil sites , which show such a spinning attack as a kind of snapshot. " The still young spider wanted to incorporate the tiny parasitic wasp as a meal , but did not have time ," says George Poinar of Oregon State University in Corvallis. Because both opponents were enrolled in this moment of liquid tree resin and so preserved forever .
Discovered have the spiders researchers Poinar and his colleagues rare find in Hukawng Valley in Burma. The lumps of amber is its information by 97-110 million years old , and thus belongs to the cretaceous period . The two enclosed therein animals are preserved down to the smallest detail, even the bristles on the legs belonging to the type Geratonephila burmanica spider and the wings of the wasp.
The Bernstein are also conserved at least 15 threads of the spider's web . Some of them were wrapped around the wasp and prove that this was caught in the net at the time of the attack, as the researchers report in the journal " Historical Biology".
There was another spider in the web
According to the scientist is at the wasp to the parasitic nature Cascoscelio incassus . Today's descendants of these species lay their eggs and larvae in spider and insect eggs. Probably the Cretaceous wasp have lived similar. The captured on the network copy is , however, been a male and thus for the spider not an immediate threat .
The lumps of amber still contained the first fossil evidence of the attack of a web spider on their prey another peculiarity , as the researchers report . For in the same network in addition to the young adult male spider a spider have stopped.
Most spiders are solitary , often even killed other dogs and ate , say Poinar and his colleagues . Normally male spiders therefore did not hesitate to attack young animals in their network. Found that two spiders of the same species in a network , the researchers therefore be regarded as a rare example of social behavior in spiders. It is also the hitherto oldest known evidence of such a phenomenon.
Spiders are arthropods that evolved at least 200 million years ago . However, the oldest fossils of spiders in a network are only 130 million years old. Evidence of two spiders in a network or even for such an attack like the one in this amber preserved were never before discovered.