One way to learn more about prehistoric life is amber — fossilized tree resin. Before it hardened, this ooze often dripped over bugs and other wildlife perched on its tree’s bark, entombing them for millions of years.

“Amber is an extremely valuable tool for paleontologists because it preserves specimens with microscopic fidelity, allowing uniquely accurate estimates of the amount of evolutionary change over millions of years,” Grimaldi said.

Scientists have now revealed arthropods trapped in 230-million-year-old amber from northeastern Italy, which appears to hold the most abundant outcrops of Triassic amber in the world. These are the oldest amber-trapped arthropods by about 100 million years, and are the first arthropods to be found in amber from the Triassic.
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These mites are unexpectedly similar to their closest relatives, modern gall mites, creatures that feed on plants and cause abnormal growths known as galls to form around them.

“You would think that by going back to the Triassic you’d find a transitional form of gall mite, but no,” Grimaldi said. “Even 230 million years ago, all of the distinguishing features of this family were there — a long, segmented body; only two pairs of legs instead of the usual four found in mites; unique feather claws.”

“The challenge for us, personally, is the tedious work required to screen through so many tiny droplets of amber — 70,000 droplets for three specimens, in this case!”