FUN FACT: the Appalachian mountains are old. Incredibly old. They saw the rise, dominance and extinction of dinosaurs. They were there before animals even came to land. In fact, they're older than trees and possibly older than the rings of Saturn (this seems to be disputed, new data suggests that the rings are far older, but it's not agreed on from my understanding)

related:
sharks are also older than trees.

...kinda?

fossils of several of the earliest known elasmobranchii, like antarctilamna are dated to the early-mid Devonian period. the middle Devonian being when plants decided that they'd finally be trees, after like 70-something million years of just laying around doing nothing.

they weren't really all that shark-like yet, though. and the things that people are saying are "shark-like" from around that time, cladoselache, were holocephali which is what chimaeriformes are, not sharks.

Related fun fact: Finland has fells formed out of remains of eroded ancient mountain range called Karelides that is estimated to be even older the Appalachian mountains. The estimate is that the mountain range was formed roughly two billion years ago, making them older than fungi and multicellular life.