Grim and disturbing for multiple reasons. It's deeply scary to me that the permafrost is melting like this and it also makes for uneasy reading to see that interesting archaeological finds are being sold off to make trinkets or simply left to deteriorate if they have no value. We're burning the world and then scrabbling around to sell the ashes.
The article focuses on China, but people in America are buying some of this stuff, too. Some (mostly boutique) American guitar manufacturers offer mammoth ivory parts.
It's kind of depressing how many ethically challenging materials are used in musical instruments and how little buyers seem to care about it. Or rather, how little buyers seem to care about the ethical problems--exotic (and often endangered) materials are seen as highly desirable.
It's almost as if to accumulate the wealth to afford a musical instrument made of exotic ivory parts (with no effect on sound) requires a certain lack of ethics in the first place.
I think you’re off by an order of magnitude. Mammoths were around as recently as 4,000 years ago. For reference that’s about when the Egyptian pyramids were being built.
I think the GP meant "If the soil has been frozen for hundreds of thousands of years, how does it contain mammoths that lived < 10000 years ago".
Either the permafrost is younger than "hundreds of thousands of years" or the mammoths are older than 4000 years.
Mammoths lived from 5 million to 4000 years ago, so it could be either.
Edit: after some research it looks like both are right. Some permafrost in Yukon formed 700 000 years ago, some permafrost formed during the last ice age 10 000 years ago, some formed in the little ice age 400-150 years ago. That's not a complete list but you get the point.
"In areas not overlain by ice, [permafrost] exists beneath a layer of soil, rock or sediment, which freezes and thaws annually and is called the "active layer". [...] Active layer thickness varies with the season, but is 0.3 to 4 meters thick (shallow along the Arctic coast; deep in southern Siberia and the Qinghai-Tibetan Plateau)"
So I guess the freeze/thaw may allow heavier object to sink in over time, and there may be rivers, earth movement (related to permafrost, or unrelated - like landslides- (see https://en.wikipedia.org/wiki/Permafrost#Landforms for examples), and other processes that deposit earth.
But the driver for this is arguably the ban. From what I've heard, people weren't using much mammoth ivory before the ban. However, permafrost thawing due to climate change has certainly made it easier to dig up.
It is sad, though, that the availability of mammoth ivory complicates enforcement of the ivory ban. Ideally, it could reduce demand for elephant etc ivory.
I'm sure that C-14 dating would work, but it's still expensive.
I've seen these pics before and have noted that, given tusks are teeth and have a large amount of phosphorus in them, surely these buried tusks must have extracted then locked up an enormous amount of bio-available phosphorus which must(?) have seriously limited that plant nutrient.
