The current Buddha, Gotama, isn't the first, even in this kalpa (age), nor is he the last. Theravada tradition tells of twenty-seven Buddhas before him, including three in this age. Gotama's the fourth of this age, and the final one will be Metteyya/Maitreya. These enlightened ones all happen on the same unchanging truth (why Donald Lopez thinks the Buddhist tradition inherently conservative), and all do so under a tree. But it's not always the same kind of tree!
As I'm learning from Asha Das' The Tree-Thrones of the Buddhas (Kolkata, 2003), Gotama chose a pipal (ficus religiosa), perhaps also the choice of the Buddha twenty-four before him, Dipamkara. Koṇāgamana, you might recall, sat beneath an Indian fig. But Maitreya will break through under a different kind of tree, the only one to have sheltered four past Buddhas, a Ceylon ironwood (messua ferrea). Hmph! How significant, then, is the pipal?