"Up until this point we have not had a place in which we have mammal and plant remains preserved in the same rocks spanning what we call the Paleocene-Eocene boundary," Bloch said. "Amazingly, these plants came from what would have been more tropical environments."
Some of the plant remains resembled those found in rock deposits of similar age unearthed in Mississippi, Louisiana and Texas, including relatives of poinsettia and sumac, Bloch said.
However, plant fossils found in the same area dating immediately before and after this period of rising temperatures reflected typical mid-latitude forests of the time and included relatives of dawn redwood, alder, sycamore and walnut, Bloch said. As temperatures cooled, floral newcomers appeared from Europe, including species of linden and wing nut. These plants probably emigrated along the same land bridges that animals traveled, he said.
Because his research specialty is mammals, Bloch said he is particularly interested in understanding how the movement of plants affected the earliest evolution of modern primates, which first appeared throughout the world during this period.
"I would very much like to know what these forests were like when these first modern primates were coming in because it has implications for how these animals lived and behaved right from the beginning," he said.
If the landscape evolved from an initially drier habitat, with patchy open spaces, into a more lush tropical forest with densely packed trees, it might have played a role in the evolution of primates' climbing skills, Bloch said. The ancestors of living primates would have been leaping through the tree canopy, foraging for fruit and insects, he said.