A 99-million-year-old ecosystem
In the Hukawng Valley of northern Myanmar, deposits of fossilized tree resin, known locally as burmite, contain an unparalleled record of a mid-Cretaceous forest. U-Pb (uranium-lead) radiometric dating of zircon crystals found within the amber-bearing layers confirms its age to be approximately 98.8 million years old. This places the amber squarely in the Cenomanian age, a time when dinosaurs still dominated the landscape. The resin is thought to have been produced by coniferous trees, possibly from the Araucariaceae family, in a humid, tropical coastal environment.
The chemical composition of burmite classifies it as a Class Ib amber, and it is Harder than the more common Baltic amber. This amber preserves a snapshot of an entire lost ecosystem with three-dimensional fidelity. The diversity of life is immense, with over 2,800 species described as of 2023. Inclusions range from fungi and the earliest examples of flowering plants to a vast array of arthropods like insects, spiders, and millipedes. The detail is so exceptional that even parasitic mites on a dinosaur feather have been identified.
