The international team of archaeologists said the lower structures were laid out on the same design as the more recent temple. The timber shrine even had an open space in the center that suggested a link to the Buddha’s nativity tradition. Deep tree roots in the center space may even have been from the tree his mother presumably held on to.

Image Archaeological evidence was discovered in Lumbini, Nepal. Credit... The New York Times

The archaeologists, led by Robin A. E. Coningham of Durham University in England, reported the findings on Monday in an article published online in the December issue of the international journal Antiquity. This was, they said, “the first archaeological evidence regarding the date of the life of Buddha.”

They also described the new line of research as having “the potential to provide yet more evidence for the earliest expressions of Buddhist architecture and ritual practice.”

Concluding its report, Dr. Coningham’s group wrote that “the sequence at Lumbini is a microcosm for the development of Buddhism from a localized cult to a global religion.” The shrine, for example, was transformed from a localized timber temple into “a monumental Asokan-period temple and pillar complex inscribing it as a site of imperial pilgrimage.”

Before the sixth century B.C., the Lumbini site was apparently cultivated land. The postholes of the timber building were the first evidence of a shrine focused around a tree, Dr. Coningham said in a teleconference for reporters arranged by the National Geographic Society, which partly supported the research, along with Durham University in England and Stirling University in Scotland.