A sulfur-rich diatom secretion coated the arachnids, helping preserve them, a study suggests
"The secret ingredient for fossil preservation at a famous French site wouldn’t be found in a Julia Child cookbook. It was a sticky goo made by microalgae, researchers suggest.
An analysis of roughly 22-million-year-old spider fossils from a fossil-rich rock formation in Aix-en-Provence, France, reveals that the arachnids’ bodies were coated with a tarry black substance. That substance, a kind of biopolymer, was probably secreted by tiny algae called diatoms that lived in the lake or lagoon waters at the ancient site, scientists report April 21 in Communications Earth & Environment.
The biopolymer didn’t just coat the spiders’ bodies — it pickled them. By chemically reacting with the spiders’ carbon-rich exoskeletons, the goo helped preserve the bodies from decomposition, allowing them to more easily become fossils, the team hypothesizes."
https://www.sciencenews.org/article/glowing-spider-fossils-diatom-algae-goo
"The secret ingredient for fossil preservation at a famous French site wouldn’t be found in a Julia Child cookbook. It was a sticky goo made by microalgae, researchers suggest.
An analysis of roughly 22-million-year-old spider fossils from a fossil-rich rock formation in Aix-en-Provence, France, reveals that the arachnids’ bodies were coated with a tarry black substance. That substance, a kind of biopolymer, was probably secreted by tiny algae called diatoms that lived in the lake or lagoon waters at the ancient site, scientists report April 21 in Communications Earth & Environment.
The biopolymer didn’t just coat the spiders’ bodies — it pickled them. By chemically reacting with the spiders’ carbon-rich exoskeletons, the goo helped preserve the bodies from decomposition, allowing them to more easily become fossils, the team hypothesizes."
https://www.sciencenews.org/article/glowing-spider-fossils-diatom-algae-goo