Middle Devonian Amber Fossil Found in China: 385-Million-Year-Old Discovery

Paleontologists working in China's Xinjiang region have unearthed the oldest chemically verified amber ever found — a collection of tiny, fossilized resin fragments dating to the Middle Devonian epoch, roughly 385 million years ago. The discovery, published in Science Advances (DOI: 10.1126/sciadv.aeh1266), pushes back the known history of amber preservation by 65 million years and suggests that plants evolved the ability to produce resin well before seed plants existed.

The previous record holder was an amber sample from the Late Carboniferous period, about 320 million years old. The new find predates that by approximately 65 million years — and by roughly 140 million years before the first dinosaurs roamed Earth.

Middle Devonian Amber Fossil in China: Key Details

The team, led by Cihang Luo of the Nanjing Institute of Geology and Palaeontology at the Chinese Academy of Sciences and the Senckenberg Research Institute and Natural History Museum, was not searching for amber. They were collecting bulk coal samples from the Hujiersite Formation near Hoxtolgay in China's Xinjiang region to study fossilized plants and the ancient environment of the Middle Devonian period.

While examining about 10 kilograms of coal, the researchers shone an ultraviolet flashlight over the material. Parts of the coal fluoresced brilliant blue — a characteristic glow often associated with amber. Using UV light, they located small clusters of amber embedded within the coal and ultimately extracted 241 tiny pieces by hand under a microscope. Most of the fragments measured just 0.1 to 0.5 millimeters across. The amber is translucent to opaque and ranges in color.

What the Amber Tells Us About Ancient Plants

Amber is fossilized resin — the sticky substance plants release to seal wounds and protect themselves from infection, pests, and wildfire damage. Resin is chemically distinct from sap; it consists of terpenoid and/or phenolic compounds that polymerize and harden upon exposure to air, forming a protective barrier. Over millions of years, under heat and pressure, that hardened resin transforms into amber.

The chemical signature of the newly discovered amber is similar to that of conifer-type plants, but the research team cannot say for certain which plant produced it. Possible candidates include tree-like lycopsids — mossy, vascularized, spore-bearing plants — or progymnosperms, woody ancestors to both gymnosperms and angiosperms. The uncertainty underscores how little is known about the earliest resin-producing plants.

The discovery suggests that resin production evolved in plants well before seed plants existed. Seed plants typically secrete resin through specialized secretory tissues on their surfaces or through internal systems associated with bark and wood. The Middle Devonian amber indicates that some earlier plant lineages had already developed this chemical defense mechanism.

Implications for Understanding Ancient Ecosystems

Amber is prized by paleontologists because it can preserve near-pristine snapshots of prehistoric life. The viscous resin sometimes traps organisms — insects, pollen, feathers, even small vertebrates — which are subsequently preserved as fossil inclusions. These inclusions provide critical information on the evolution of terrestrial ecosystems.

While the newly discovered fragments are too small to contain visible inclusions, their mere existence extends the known window for amber preservation by tens of millions of years. It raises the possibility that older amber deposits, perhaps with trapped organisms, may yet be found in similarly ancient coal seams.

The find also highlights the value of UV light as a screening tool. The amber fragments were invisible to the naked eye within the dark coal; only under ultraviolet light did they reveal themselves. This technique could be applied to other coal deposits from the Devonian and earlier periods, potentially yielding more ancient amber.

A New Benchmark for Amber Research

The study, published in Science Advances (DOI: 10.1126/sciadv.aeh1266), establishes the Hujiersite amber as the oldest chemically verified fossil resin on record. The previous record-holder, from the Late Carboniferous, was about 320 million years old. The new find extends the known history of amber preservation by 65 million years.

For context, the Devonian period is often called the Age of Fishes, but it was also a time of dramatic change on land. Plants were diversifying rapidly, with the first trees and forests appearing. The evolution of resin production would have given these early plants a significant advantage in defending against herbivores and pathogens.

The discovery was made possible by careful, painstaking work — extracting hundreds of sub-millimeter fragments from coal by hand under a microscope. It is a reminder that major paleontological finds often come not from dramatic excavations but from patient laboratory analysis.

As researchers continue to study the Hujiersite Formation and other Devonian deposits, they may uncover more amber — and perhaps even inclusions that reveal the organisms that lived alongside these ancient resin-producing plants. For now, the tiny, 385-million-year-old fragments from China stand as the oldest known testament to a defense mechanism that plants still use today.