Spider and Wasp Frozen for Eternity in Death Dance, Preserved in Amber
It’s rare to catch a spider in the act of killing a bug—and rarer still for a drop of resin to engulf the arachnid as it's on the verge of pouncing. Even rarer than that is having the moment preserved in amber for 100 million years, and then discovered by humans.
Talk about a needle in a haystack.
The amber-interred fossils of a young spider and the parasitic wasp it was about to feast on were preserved in the Hukawng Valley, Myanmar, in the Early Cretaceous period between 97 and 110 million years ago, researchers at Oregon State University (OSU) announced on October 9. It’s the oldest and only known fossil of its kind, the university said.
“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., professor emeritus of zoology, in a statement from OSU. “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.”
Poinar, an internationally known expert on insects trapped in amber, detailed his findings in the journal Historical Biology. He is in fact the entomologist whose work inspired the movie Jurassic Park, according to Discovery Magazine.
Although perhaps a movie could be made of this frozen-in-time moment—there’s certainly enough drama encapsulated in the resin drop—it would not include bringing them back to life as a plot element. A study in the journal Proceedings of the Royal Society B, reported by LiveScience.com, found DNA’s rate of decay and enabled scientists to say with near certainty that one could not resurrect a creature after that amount of time.
The team of scientists at Murdoch University’s Ancient DNA Lab in Perth, Australia, estimated a 521-year half-life for the building block of life by analyzing the DNA from 158 fossilized leg bones of an extinct, flightless bird hailing from New Zealand called the moa. The bones ranged from 600 to 8,000 years old and were from the same region, which allowed the researchers, headed by Mike Bunce, to determine the length of time it would take for the DNA bonds to break down. The rate was much slower than what they expected to find and showed that it would take 6.8 million years to completely destroy the DNA bonds in the bone, LiveScience.com said.
Spiders are thought to be 200 million years old, according to the OSU release, though the oldest fossil only dates back about 130 million years. This is the only fossil known to exist of a spider and its prey in mid-kill, the researchers said in the statement. But dinosaurs were likely around at the time of the dramatic moment.
Amber is formed from resin of the perfect consistency to envelope and preserve insects, small plants and other forms of life, OSU said. The samples in this fossil are from an extinct branch of the species, the university said, but the wasp is the same as a modern version that feeds as a parasite on spider and insect eggs.
“In that context, the attack by the spider, an orb-weaver, might be considered payback,” the OSU statement said. “Its large and probably terrified eyes now stare for eternity at its attacker, moving in for the kill.”