Researchers have found what they say is the only fossil ever discovered of a spider attacking prey caught in its web – and it dates back 100 million years.
The extraordinarily rare fossils are in a piece of amber that preserved this event in remarkable detail, an action that took place in the Hukawng Valley of Myanmar in the Early Cretaceous between 97-110 million years ago. Aside from showing the first and only fossil evidence of a spider attacking prey in its web, the piece of amber also contains the body of a male spider in the same web. This provides the oldest evidence of social behavior in spiders, which still exists in some species but is fairly rare. Most spiders have solitary, often cannibalistic lives, and males will not hesitate to attack immature species in the same web.
Spiders are ancient invertebrates that researchers believe date back some 200 million years, but the oldest fossil evidence ever found of a spider web is only about 130 million years old. An actual attack such as this between a spider and its prey caught in the web has never before been documented as a fossil, the researchers said.
The tree resin that forms amber is renowned for its ability to flow over insects, small plants and other life forms, preserving them in near perfection before it later turns into a semi-precious stone. It often gives scientists a look into the biology of the distant past. This spider, which may have been waiting patiently for hours to capture some prey, was smothered in resin just a split second before its attack.
The only fossil ever discovered that shows a spider attacking prey in its web. Preserved in amber, it's about 100 million years old. Photo: Oregon State University.
“This juvenile spider was going to make a meal out of a tiny parasitic wasp, but never quite got to it,” said George Poinar, Jr., a professor emeritus of zoology at Oregon State University and world expert on insects trapped in amber. “This was a male wasp that suddenly found itself trapped in a spider web. This was the wasp’s worst nightmare, and it never ended. The wasp was watching the spider just as it was about to be attacked, when tree resin flowed over and captured both of them.”
This type of wasp, Poinar said, belongs to a group that is known today to parasitize spider and insect eggs. In that context, the attack by the spider, an orb-weaver, might be considered payback.
Both the spider and the wasp belong to extinct genera and are described in the paper. At least 15 unbroken strands of spider silk run through the amber piece, and on some of these the wasp was ensnared.
Its large and probably terrified eyes now stare for eternity at its attacker, moving in for the kill.
Published in the journal Historical Biology.
- PHYSICAL SCIENCES
- EARTH SCIENCES
- LIFE SCIENCES
- SOCIAL SCIENCES
Subscribe to the newsletter
Stay in touch with the scientific world!
Know Science And Want To Write?
- Nobel Prize To Neutrino Oscillations
- What Is Fat For?
- Machine learning vs NRA, a Grand Challenge
- Lung Cancer Screening Programs Do Not Increase Rates Of Unnecessary Surgeries
- Inflammatory Response May Fan The Flame Of Dietary Fats' Role In Obesity-related Diseases
- Thank You Guido
- Environmental Activism Puts NYC At Risk Of Future Flooding During Hurricanes
- "Hello Luis,thanks for the note. Indeed the field of neutrino physics is acknowledged for the important..."
- "Hi Tommaso,Masatoshi Koshiba and Raymond Davis Jr. got already (for a half) the 2002 Nobel Prize..."
- "You completely skipped the exercise of starting with the multiplication group with 6 elements and..."
- "I hope you are right. I have seen the way many people think by teaching basic science. ..."
- "Real science is much more complicated. Here's the scoop:In order to have autoimmune disease, there..."
- Peeking into our galaxy's stellar nursery
- Dengue epidemics and strong El Nino season
- Ancient alga knew how to survive on land before it left water & evolved into first plant
- Stress in adolescence prepares rats for future challenges
- Testosterone levels improve in obese men following sleeve gastrectomy weight-loss operation