In my neighborhood the big Osage oranges were planted in the late 1800s along the property lines, so they are long lived. A once in a hundred year weather event would be enough to keep a population going.
The concept of a tree that propagates by tornado is hilarious, but somehow not unbelievable.
The article notes that it was nowhere near enough, and with the loss of its primary dispersers the once-widespread genus had enormously shrunk in variety and range both before it got recycled as natural fencing:
> According to my field guide, Osage-orange has a limited natural range in the Red River region of east-central Texas, southeastern Oklahoma, and adjacent Arkansas.
> [...]
> fossils tell us that Osage-orange was much more widespread and diverse before the megafaunal extinctions. Back then, Osage-oranges could be found north up to Ontario, and there were seven, not just one, species in the Osage-orange genus, Maclura.
(sp: there are 12 extant species of Maclura according to the wiki — most of them from asia though one is native to south america and one central america, I expect the author implied "in NA")
(Everybody underestimates the ant power)
Being an anachronistic species is not necessarily an inevitable decline. I have a magnolia tree in my front yard — the leaves and petals are frustratingly indestructible, because it was once beetle-pollinated long before bees existed. I wonder how many anachronistic species will do well in the future changed climate. I know dawn redwood has a small range now, in China, but their fossils are found in Alaska.
Glad to see them take on the "pristine forest" thing, ecologies are complex open systems. Human activity doesn't do them any favors, for sure, but also there's no edenic prior state to which they can be returned. The only way out is forward.
There's a lot of discussion if these were adaptations to browsing by moa.
http://nzetc.victoria.ac.nz/tm/scholarly/tei-Bio32Tuat-t1-bo...
The best evidence now is that a meteor strike on the Canadian ice shield wiped out most of the megafauna, and the Clovis culture, at one stroke, initiating the 1200-year Younger Dryas cold spell. The damage reached as far as Syria and southern Africa, leaving a layer of platinum-enriched dust.
But then I'm not claiming that it was all Homo sapiens - rather, climatic change had already placed species under stress, then man was the final stressor that pushed them over the brink.
Beware that the wikipedia page on the topic is "curated" by a retired busybody professor who reverts corrections that do not favor his bias.