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Comment by hprotagonist | Hacker News Reader

and they are ooooold. Older-than-trees old.

Not only older than trees, but older than dirt.

Literally.

Dirt, in the sense of organic topsoil, requires plant life, and often the action of burrowing insects, reptiles, and mammals to form. The Appalachian range formed about the same time that life was first colonising land, ~480 mya, and it's likely that soil formation post-dates this by a significant extent.

This also means that the Appalachians have some of the oldest rivers in the world, including the ... inaccurately named ... New River, the Susquehanna, and French Broad River, all dating to ~260--340 mya.

https://en.wikipedia.org/wiki/List_of_rivers_by_age

> This also means that the Appalachians have some of the oldest rivers

In the case of the New River (unsure about the others), it is the other way around: the river is not old because the mountains are old, but the mountains are old because the river is older. The New River predates the mountains that surround it.

Fair point, and I'd known that once.

That said, the river runs through the Appalachians, and is quite old.

There's a meme that criss-crosses Facebook from time to time that notes that in general, one doesn't find any skeletal remains in the rock formations in the Appalachians. You might find them washed into a cave, but you won't find any in the rock itself, as those mountain formations predate the evolution of skeletons.

Older than bones, older than bones.

Wikipedia says trees have been in existence for 370 million years. Are these mountains even older than that?

yep! by about 80-100 million years.

They're probably older than dirt.

https://news.ycombinator.com/item?id=32373985

Younger than the mountains, growin' like a breeze.

and separated for much of that time. at some point the unique life experience of each side of the range renders them individual; it might be more proper to say they're descendants of the single original range.

On the other hand if we could convince them to get back together the shipping costs to Europe would plummet and that would be good for the economy.

I am all for a direct rail service from the Highlands to Appalachia

https://en.wikipedia.org/wiki/Tunnel_Through_the_Deeps

But a lot younger that a lot of other mountains (though not the Alps, Rockies, Himalayas, or Andes).

https://en.wikipedia.org/wiki/List_of_orogenies

Aren’t most mountains older than trees? Maybe even all of them?

Certainly not all, e.g. trees are ~8x older than the Himalayas. I think trees might actually even be slightly older than the Central Pangean Mountains.

I suspect gp may have been referring to specific mountains and specific trees, not trees as a species.

No, they were referring to trees in general. As in, this particular mountain range has existed since before the first tree evolved on earth.

Edit: My mistake, thought you were referring to the original “older than trees” comment.

No I wasnt.

hprotagonist was

Correct.

Many mountain ranges are surprisingly young, geologically speaking. They rise quickly, but also erode rapidly. The tallest ranges (Himalaya, Andes) are relatively young, at roughly 20--50 mya based on a quick Wikipedia read.

The higher and more rugged the range, the younger, in all likelihood.

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