100-page indictment dance party open thread

I think so.

If there are only 25 comments, why is yours on a page by itself?

Since it’s relatively quiet here, I’d like to post some lengthy musings on a personal nerdy interest.

Lately, I’ve been obsessed with sabertoothed cats. Some of the following three-part monologue discusses things I’ve briefly mentioned here before. However, thanks to Twitter’s awesome paleo community, I was recently inspired to rehash the topic and study it further. I also posted this in the never-ending community thread at the Affinity blog.

ti;dr on sabertoothed cats: They hunted the mammoth, too.

(I tried to use the edit function to correct the spelling of “tl;dr”, but when pressing Save, I just got a notice saying I should slow down on my posting frequency. My next comment, posted as a test immediately after that, went into some kind of approval limbo, and now shows as time-stamped 1 hour later.)

The smilodon is the official state fossil of California. (It beat the trilobite) There are a lot of them all over the state. Having seen skeletons, I would not have wanted to be one of the first Californians going up against one. Although they are extinct now, so I guess the humans did OK.

I really liked that sword fight video at the beginning of the thread!

More than 50 years ago, at a children’s Christmas party at my father’s workplace, my Christmas cracker had a Sabre tooth tiger ornament inside! I still have it. They were made by Wade, probably as part of a set relating to the Flintstones cartoon. It’s a cheerful little thing, and probably initiated my interest in sabretooths.

Naturally, there is no direct evidence of Homotherium, or Neandertals, or much anything else living in Sweden or Finland during the Pleistocene. The repeated glaciations in Scandinavian region have destroyed nearly all previous soil sediments, including in lakes and shallow seabed, that could contain subfossil/fossil animal bones or human archaeological remains. This is continuation of the erosion that has, over many millions of years, scraped away any fossil-bearing sediment rocks that formed in the region over the last billion years, leaving only the ancient Precambrian metamorphic bedrock. The bedrock itself is so solid there’s almost no caves that could’ve preserved bones or human artifacts under the glaciations.

Some evidence does exist, though – mainly of the woolly mammoth. They were apparently relatively common, compared to most other animals in northern areas, and had big sturdy bones that preserved easily.

Most of the Late Pleistocene (defined as being 130,000 – 12,000 years ago) coincides with the last ice age (115,000 – 12,000 years ago), which is formally called the Weichselian glaciation in northern Europe and by other names in other regions (I think Devensian in UK, Wisconsin in US). For much of this ice age, Finland is thought to have been mostly or entirely free of ice, covered with arctic tundra, or sometimes even forest in the south. Total glaciation took place at least 70,000 – 60,000 years ago (early Middle Weichselian) and again 25,000 – 12,000 years ago (Late Weichselian). In some nooks and crannies of the bedrock, patches of old soil sediment have survived from before Middle Weichselian, or even from before older ice ages. There is evidence of a beaver dam in one place, but no actual animal bones have been found in these deposits.

A few isolated mammoth bones and one reindeer antler have been found in secondary deposits in Finland, and dated to the milder period between 60,000 – 25,000 years ago. These were dislocated from their original deposits (likely peat bogs) by the Late Weichselian ice sheet and then deposited (probably not far away) in the till or gravel that formed in some sheltered spots between the ice and bedrock. This is a far cry from the unglaciated areas of Europe, let alone Siberia where the permafrost has preserved huge amounts of mammoth bones and the occasional frozen carcass. Nevertheless, it lends some support for the speculation that a rich subarctic-arctic fauna (and potentially even humans) did live in Finland during the milder parts of last ice age.

Over here, the ice sheets were more concentrated in the North. That has an interesting effect. The weight of the ice squished the North down. So now the ice has gone, the North is slowly springing back and the South is getting lower as the whole island pivots. That has an effect on sea levels.

This same process (inequal glacio-isostatic rebound) has had a huge effect on Finland and Sweden in postglacial times, since the terrain is relatively flat and the depression of land was rather strong around the northern end of Gulf of Bothnia, where the Scandinavian ice sheet was thickest. In southern Finland, the lake basins continue tilting from the northwest to southeast, occasionally switching to new outflow routes.

The interplay between glacio-isostatic adjustment, ocean level changes and the blockage of drainage basins by glaciers has had fascinating effects on landscape. For example, most of the North Sea and English Channel was dry land during the colder parts of ice ages, because much ocean water was tied up in continental ice sheets. But sometimes, during extreme glaciation, the Scottish and Scandinavian ice sheets merged together near the Shetlands and blocked the drainage of the North Sea region northwards. A huge glacial lake then formed, collecting water from rivers across much of northern Europe, and overflowed into the valley that was English Channel, and west into the Atlantic. Then, when the glaciers began receding and parted in the north, the lake abruptly emptied, leaving behind a giant arctic mudflat.

When this lake formed for the first time, hundreds of thousands of years ago, its violent outflow in the Dover Strait eroded the landscape by tens of meters, after a massive buildup of water in the North Sea basin, resulting in a giant waterfall. Prior to that, there was a low ridge running across the Dover strait that would be above the sea level even during interglacial times, such as now. In other words, Britain was separated from the continent by a huge glacial lake outburst.

Oh, and there may also be an impact crater there. Silverpit.

The science suggests it’s more likely to be a salt collapse; but impact can’t be ruled out.

As the most common estimate for the age of the crater is about 65 million years, that throws up some intriguing speculation.

Since the topic of paleontology seems to have resumed: it’s a great misfortune that David went on hiatus just as this discussion surfaced on Tumblr. It begins with a mention of the Flat Earth trope (and how The Ancients™ knew better) with a passing reference to negligent toilet hygiene, veering into what initially seem to be harmless Fun Facts about mammoth genetics—only to take an abrupt right turn straight into the Manosphere Zone; this could’ve have been custom designed as WHTM fodder.

https://mondengel.tumblr.com/post/726366480230383616/people-today-with-access-to-more-raw-information#notes

@Alan: Indeed. And considering feminism as an idea and mammoths didn’t overlap, it deserves an extra WTF. Women hunted the mammoth, but they presumably killed them with spears and arrow, not feminism.

I love the roasting the replies gave him. I wanna be friends with the geneticist who explained it all AND came up with such fabulous insults. “self-satisfied jellyfish fellator” was my favorite.