China Discovery Pushes Amber Record Back 65 Million Years to 385 Million

Q: If not for insects, what ancient threat drove trees to evolve protective resin 385 million years ago?

The evidence points to **fire damage and microbes, not insects, as the main early pressure**. Researchers say the newly discovered 385-million-year-old amber comes from a time when there is little fossil evidence of arthropods boring into trees. That makes insect attack a less likely driver for the earliest resin production. Instead, the team argues resin probably evolved as a wound-sealing defense against **microbial infection** and **fire-related injury**. That fits what resin does biologically. It is not sap, but a chemical exudate that hardens on contact with air, forming a protective seal over damaged tissue. In effect, it acts like a scab, helping block pathogens such as fungi and bacteria and limiting further harm after injury. The Devonian world also makes the fire explanation plausible. Early forests were spreading across warm, often dry landscapes, conditions that could have increased wildfire risk. In that setting, a substance that quickly sealed damaged bark or wood would have offered a major survival advantage. So, if not insects, the ancient threat was most likely **a combination of wildfire damage and microbial pathogens**.

3 articles · Updated · Nautilus · Jul 15

Tiny amber crystals found in coal from China’s Hujiersite Formation date to 385 million years ago, making them the oldest amber yet identified.
The Science Advances study pushes the known origin of resin back by 65 million years from the previous oldest amber, dated to about 320 million years ago in the Carboniferous.
That earlier date suggests Devonian trees evolved resin production sooner than thought, likely using it to seal wounds and defend against microbes or fire damage.
Chemical signatures resemble amber from conifer-type plants, but researchers said the source was more likely a tree-like lycopsid or a progymnosperm.