5 ms·

The Mesozoic terminated in boreal spring

75 points by Someone 5y ago

changoplatanero 5y ago
boreal means in the northern hemisphere. so it means that the meteor that killed the dinosaurs hit the earth when it was spring in north america. Different species are more or less vulnerable in each season. Species that were hibernating at this time had a better chance of survival and in general species in the southern hemisphere did better because it was fall there and it was a less critical time for most species.
lanstin 5y ago
Wow, such detailed deductions are possible about the day of the impactor, I had no idea. I really want to put Hell's Creek on my to visit list now. Fascinating and, for Nature, very accessible article.
cecilpl2 5y ago
TL;DR Sturgeon fins grow bone similarly to tree rings - in annual layers. By studying the outermost layer of many samples found on the K-Pg boundary they were able to deduce that they all died in spring. Corroborating evidence is found from some other fish exhibit seasonal variation in their C13/C12 ratios due to food availability.
reactspa 5y ago
The Tanis site is one of the most interesting fossil sites in the world. It contains evidence of the Chicxulub impact (K-T boundary [now called K/Pg boundary], end of the dinosaurs) from 65 million years ago. It contains fossils believed to be from the day of the impact. There are well preserved fossils from multiple animal-types (fish, dinos, dino eggs, marine reptiles). And also spherules (little round balls of melted rock) from the actual impact that somehow made their way there from what is now Mexico. I live a couple hours away from the Tanis site. And I have my summers off. If anyone connected with any of the digs needs someone with my skills, and can give me pointers on how I can get involved, I'd appreciate it. My email is in my profile. I can code (in order of preference) SQL, JS, PHP, R, Python. I have a large house within 2 hours of Tanis (to accommodate guests), and a 4-by-4. A great interest of mine is information storage and fast retrieval (so... databases). I can photograph. But I really want to get my hands dirty in a dig.
andrewflnr 5y ago
This is the first published article I've seen that references the Tanis site. It wasn't totally clear that it was ever going to be accepted as real. Very cool that it apparently has.
brimble 5y ago
I checked, and the Tanis fossil site is, in fact, named after the ancient Egyptian city of Raiders of the Lost Ark fame. https://en.wikipedia.org/wiki/Tanis_(fossil_site)#Discovery_and_exploration_of_'Tanis' https://en.wikipedia.org/wiki/Tanis_(fossil_site)#Discovery_...
Simon_O_Rourke 5y ago
I never heard of Tanis before, and the first thing that popped into my head was Indiana Jones. But reading up on what they found in North Dakota Tanis is damn interesting, even without Indy having a gemstone on the end of a stick ;) https://en.m.wikipedia.org/wiki/Tanis_(fossil_site) https://en.m.wikipedia.org/wiki/Tanis_(fossil_site)
ridgeguy 5y ago
This 2019 New Yorker article about the Tanis site is a fascinating read. https://www.newyorker.com/magazine/2019/04/08/the-day-the-dinosaurs-died https://www.newyorker.com/magazine/2019/04/08/the-day-the-di...
jongalloway2 5y ago
There's a really clear minute summary video by the first author on this paper: https://www.youtube.com/watch?v=jdshml5515o https://www.youtube.com/watch?v=jdshml5515o

75 points by Someone 5y ago

boreal means in the northern hemisphere. so it means that the meteor that killed the dinosaurs hit the earth when it was spring in north america. Different species are more or less vulnerable in each season. Species that were hibernating at this time had a better chance of survival and in general species in the southern hemisphere did better because it was fall there and it was a less critical time for most species.

lanstin 5y ago

Wow, such detailed deductions are possible about the day of the impactor, I had no idea. I really want to put Hell's Creek on my to visit list now. Fascinating and, for Nature, very accessible article.

cecilpl2 5y ago

TL;DR Sturgeon fins grow bone similarly to tree rings - in annual layers. By studying the outermost layer of many samples found on the K-Pg boundary they were able to deduce that they all died in spring. Corroborating evidence is found from some other fish exhibit seasonal variation in their C13/C12 ratios due to food availability.

reactspa 5y ago

The Tanis site is one of the most interesting fossil sites in the world. It contains evidence of the Chicxulub impact (K-T boundary [now called K/Pg boundary], end of the dinosaurs) from 65 million years ago. It contains fossils believed to be from the day of the impact. There are well preserved fossils from multiple animal-types (fish, dinos, dino eggs, marine reptiles). And also spherules (little round balls of melted rock) from the actual impact that somehow made their way there from what is now Mexico. I live a couple hours away from the Tanis site. And I have my summers off. If anyone connected with any of the digs needs someone with my skills, and can give me pointers on how I can get involved, I'd appreciate it. My email is in my profile. I can code (in order of preference) SQL, JS, PHP, R, Python. I have a large house within 2 hours of Tanis (to accommodate guests), and a 4-by-4. A great interest of mine is information storage and fast retrieval (so... databases). I can photograph. But I really want to get my hands dirty in a dig.

andrewflnr 5y ago

This is the first published article I've seen that references the Tanis site. It wasn't totally clear that it was ever going to be accepted as real. Very cool that it apparently has.

brimble 5y ago

I checked, and the Tanis fossil site is, in fact, named after the ancient Egyptian city of Raiders of the Lost Ark fame. https://en.wikipedia.org/wiki/Tanis_(fossil_site)#Discovery_and_exploration_of_'Tanis' https://en.wikipedia.org/wiki/Tanis_(fossil_site)#Discovery_...

Simon_O_Rourke 5y ago

I never heard of Tanis before, and the first thing that popped into my head was Indiana Jones. But reading up on what they found in North Dakota Tanis is damn interesting, even without Indy having a gemstone on the end of a stick ;) https://en.m.wikipedia.org/wiki/Tanis_(fossil_site) https://en.m.wikipedia.org/wiki/Tanis_(fossil_site)

ridgeguy 5y ago

This 2019 New Yorker article about the Tanis site is a fascinating read. https://www.newyorker.com/magazine/2019/04/08/the-day-the-dinosaurs-died https://www.newyorker.com/magazine/2019/04/08/the-day-the-di...

jongalloway2 5y ago

There's a really clear minute summary video by the first author on this paper: https://www.youtube.com/watch?v=jdshml5515o https://www.youtube.com/watch?v=jdshml5515o