A family circle of fossilized redwood stumps grew from the single trunk of an older parent tree, and the three trunks are ancient clones, or genetically identical copies, of that parent tree. Modern coastal redwoods also reproduce by stump sprouting: if a redwood is toppled or burned, a ring of new trees often sprouts from burls around the trunk's base. Family groups are common in coastal redwood forests, but this trio of stone stumps is unique in the world's fossil record. In the Eocene, when the Florissant redwoods were growing, redwood tree species were common around the globe, as shown by analyses of fossil foliage, wood, and pollen. If the main trunk of a redwood is damaged, dormant stems begin growing rapidly, using the parent tree's root system for nourishment and support. Harry D. MacGinitie, a paleobotanist who excavated fossils at Florissant in 1936 and 1937, produced the most comprehensive published study of Florissant's fossil plants and was the first to compare these fossils with modern forests to reconstruct past climate, ecology, and elevation.