The Cretaceous-Paleogene extinction event wiped out non-avian dinosaurs and devastated global plant life through prolonged impact winter, soot-blocked sunlight, and widespread forest die-offs. Yet, Ginkgo biloba endured. To understand how this singular species survived, geneticists sequenced the massive Ginkgo genome, which spans roughly 10.
6 billion base pairs—over three times larger than the human genome. This immense genomic footprint is heavily enriched by ancient whole-genome duplication events and extensive expansions of gene families dedicated to stress resistance and chemical defense. Ginkgo possesses an unusually high number of genes regulating the synthesis of secondary metabolites, such as flavonoids and ginkgolides, which protect the tree from herbivores, fungal pathogens, extreme cold, and radiation.
Furthermore, the tree maintains vast redundancy in its stress-response pathways. When environmental stressors like nuclear fallout, toxic atmospheric gases, or prolonged darkness occur, redundant gene copies ensure that loss of individual pathways does not trigger cellular failure. Ginkgo trees also exhibit remarkable somatic longevity and developmental flexibility; specialized dormant buds called lignotubers can remain protected underground for decades, sprouting new clones after catastrophic damage to the main trunk.
This combination of genetic duplication, metabolic warfare capabilities, and underground physical resilience allowed Ginkgo to weather the fallout of the Chicxulub asteroid and millions of years of climate shifts, earning its status as the ultimate botanical living fossil.