12 ms·

Why birds can fly over Mount Everest (2020)

250 points by Phithagoras 5y ago

einpoklum 5y ago
Wow, that story is amazing well-written. I would definitely tell it to my kids (if and when I have them).
ripvanwinkle 5y ago
This is very well written, I now have a story to read to my son this weekend. On that note, I'd welcome pointers to similar narratives that explain evolution, the formation of the planet, the universe etc.
- blmurch 5y ago
  My father wrote that and he just changed the opening line to include all of his grandchildren, not just his niece as he originally wrote it. I will be reading it to David in the near future. He's only 6. I don't know of any other narratives, but I know he was talking to John Lasseter about Lignin to maybe get the idea into movie form.
dmd 5y ago
If you remove the word 'can' from the title, you get another interesting question, and some scientists think the answer is that the bar-headed geese have been doing it since before there was a mountain range there!
- pvg 5y ago
  If that's true they've also been pigheaded since before there were pigs which probably explains the name.
- jhgb 5y ago
  > bar-headed geese have been doing it since before there was a mountain range there The Himalayas formed fifty millions years ago. Geese apparently appeared ten million years ago. How would this be possible?
  - dmd 5y ago
    They weren't nearly that tall then though. E.g.: > “The bar-heads have done that migration for millions of years before the Himalayas were as tall as they are now, and the birds have been pushed as the mountains have moved up to go higher and higher,” says coauthor Julia York, now a graduate student at the University of Texas at Austin, in an interview with the Times. York, who played foster parent to seven geese, adds, “They’re amazing athletes.” https://www.the-scientist.com/news-opinion/bar-headed-geese-slow-their-metabolism-to-soar-over-everest-66386 https://www.the-scientist.com/news-opinion/bar-headed-geese-...
    - jhgb 5y ago
      The mountain range may have been significantly less tall back then but I'm quite sure it had already existed before any species of geese appeared.
  - gerdesj 5y ago
    It wasn't that particular species at the time but a precursor. Your grandad is/was hom. sap. sap. but your (50,000,000 / 20)th grandad was one of quite a few possibilities, mostly ape and no sign of homo. I'm using a simple 20 year per generation model here. That's 2,500,000 generations ago. Here in the UK on telly, a comedian was shown how his (2021 - 1239) / 20 = 39 or so generational ancestor was English King Edward I - "longshanks". 39 generations gets you to 1230 or so, 2,500,000 generations is quite a long time ago. So, let's look at these geese. 50M years back, the "dinosaurs" flying that route - let's call them "Goosey" - already had phenomenally efficient lungs compared to say mammals. As the land rose, they simply adapted a bit. Given how efficient their lungs are I doubt there was much to do. It looks miraculous to us but we don't have those lungs. We didn't evolve the double ended lungs and hollow bones etc because we simply didn't need them or the cost of some part of that mix was detrimental for our use case or "we" simply rolled a double three. Evolution is weird. Well, no it isn't, that implies a blind watchmaker/intelligent design or nonsense as I prefer to call it. In the words of a famous bloke: "Evolution is as evolution does". No more and no less. There are some geese that are able to fly over some mountains.
    - 5y ago
smegcicle 5y ago
tldr bird respiratory system is very effective, they breathe in one end of their lungs and out the other, always with either a full breath in their lungs or two breaths in their air sacs (one fresh, one ready to be exhaled) http://www.lslbo.org/wp-content/uploads/2018/10/bird-lungs.jpg http://www.lslbo.org/wp-content/uploads/2018/10/bird-lungs.j...
- Mountain_Skies 5y ago
  We already have artificial continuous flow hearts, next up: continuous flow lungs.
  - polishdude20 5y ago
    Like a literal jet engine. Continuous flow of air
    - redis_mlc 5y ago
      1) jet engines are interesting because of the continuous flow and also that all the rotating parts rotate in the same direction, a huge advantage over reciprocating engines. So jet engines can do 50,000 rps, while piston under 20,000 rps. Note that sleeve piston engines like the Rolls Royce Crecy, are much more efficient than valves, but development stopped at the end of WW2 and resources focused on jet engines. Rolls Royce Crecy - The Most Advanced Piston Aero Engine Never Made https://www.youtube.com/watch?v=cxK_zWgw6gY https://www.youtube.com/watch?v=cxK_zWgw6gY 2) the exception to continuous flow is the WW2 V-1 pulsejet engine, which has a gate that is closed at combustion time, about 42 Hz. The pulsejet is a very interesting engine in that it's the simplest possible jet engine - literally an empty metal tube with spray nozzles and a sparkplug. The V-1 was the first mass-produced cruise missile. The Germans also had air-to-ground (anti-ship) guided missiles both wire-guided and radio-guided with a TV screen(!) But the US Navy was the first to build precision-guided autonomous missiles, both the all-analog Sidewinder and Wall-eye, which shared modules. The Wall-eye made the famous Gulf War photos you've seen of entering via windows. It had analog circuitry to do edge-detection in real-time.
simorley 5y ago
So that's what dinosaur tastes like.
ARandomerDude 5y ago
It's not a question of where he grips it! It's a simple question of weight ratios! A five-ounce bird could not carry a one-pound coconut.
- icelancer 5y ago
  African swallows are non-migratory, man.
dang 5y ago
One past thread: Why Birds Can Fly over Mount Everest - https://news.ycombinator.com/item?id=23639294 https://news.ycombinator.com/item?id=23639294 - June 2020 (96 comments)
aspectmin 5y ago
I love reading both Nautilus and Quanta. Great articles.
m463 5y ago
an interesting thing is that though birds have super-efficient lungs, they can be very fragile. As any parrot owner knows, if you overheat a teflon pan, all the birds inside your house will die. So bird owners use stainless steel. There are other non-stick pans available, but it's really hard to wade through the marketing to figure out if overheating will kill the pet that's been in your family for years or even decades. unrelated, the name of this article made me wonder if it was about thin air and lift, thinking how helicopters can't fly over everest. But a mountain like everest might have a huge amount of updrafts to lift birds into the sky. If you've ever stopped at an ridge overlook along california highway 1, you might see something curious. the ridges are bird-superhighways. the ocean air hits the cliffs and deflects upwards, and this updraft lets birds "surf" up and down the coast. So if you stand there and are patient, you'll see lines of gulls cruise by going north or south without flapping.
- deckard1 5y ago
  efficiency and fragility seem to go together (see our current global container shipping fiasco and our just-in-time production world) The life at the deepest points of the ocean also seem quite fragile. Also, "canary in the coal mine". Canaries were sent into coal mines to detect carbon monoxide and other gases because they were more sensitive than humans. The bird would die before humans, giving an early warning.
- photonic37 5y ago
  If you’re in the Bay Area, you can stop by Fort Funston and see humans using this effect as well. In the hang gliding world, ridge lift is a wonderful phenomenon that enables one to stay airborne almost indefinitely, with much better predictability than thermal soaring. The lift band is well defined by the incoming wind and upward deflection. When you’re done, just turn inland and exit the lift band.
  - ofcrpls 5y ago
    Same thing at Torrey Pines, if you are in San Diego.
- 5y ago
blacklight 5y ago
The author seems to pinpoint the cause of the great Permian-Triassic extinction to the acquired ability of microorganisms to process lignin, while most of the researchers attribute it to the extensive Siberian Traps eruptions. Granted, decaying lignin subtracts oxygen from the atmosphere, but had that happened alone the levels of oxygen would have gone down quite slowly. What we see instead is a drop from ~30% to 12% within a few hundreds of thousands of years. It means that a catastrophic event (such as prolonged supervolcanic eruptions) probably played a bigger role.
- kashkhan 5y ago
  Even if you converted all the atmospheric CO2 to O2, oxygen levels will not increase by more than 1%. So where did the rest come from and go to?
  - rsj_hn 5y ago
    It came from CO2 and other carbon gasses. IIRC, according to current theory, there were 3 major climates in the earth. In the first climate, the atmosphere was volcanic gasses, many of which were blown off into space, leaving the second climate of carbon gases as a residue, and then this was absorbed into rocks as well as consumed by CO2 breathing lifeforms. https://www.nature.com/scitable/knowledge/library/earth-s-earliest-climate-24206248/ https://www.nature.com/scitable/knowledge/library/earth-s-ea...
jonnycomputer 5y ago
has the lignin story held up though? Wikipedia's article on Coal suggests that a 2016 paper "refuted" the idea. I don't really follow this area of research, so would be happy if someone more knowledgeable chimed in about it.

250 points by Phithagoras 5y ago

Wow, that story is amazing well-written. I would definitely tell it to my kids (if and when I have them).

This is very well written, I now have a story to read to my son this weekend. On that note, I'd welcome pointers to similar narratives that explain evolution, the formation of the planet, the universe etc.

blmurch 5y ago
My father wrote that and he just changed the opening line to include all of his grandchildren, not just his niece as he originally wrote it. I will be reading it to David in the near future. He's only 6. I don't know of any other narratives, but I know he was talking to John Lasseter about Lignin to maybe get the idea into movie form.

dmd 5y ago

If you remove the word 'can' from the title, you get another interesting question, and some scientists think the answer is that the bar-headed geese have been doing it since before there was a mountain range there!

pvg 5y ago
If that's true they've also been pigheaded since before there were pigs which probably explains the name.
jhgb 5y ago
> bar-headed geese have been doing it since before there was a mountain range there The Himalayas formed fifty millions years ago. Geese apparently appeared ten million years ago. How would this be possible?
- dmd 5y ago
  They weren't nearly that tall then though. E.g.: > “The bar-heads have done that migration for millions of years before the Himalayas were as tall as they are now, and the birds have been pushed as the mountains have moved up to go higher and higher,” says coauthor Julia York, now a graduate student at the University of Texas at Austin, in an interview with the Times. York, who played foster parent to seven geese, adds, “They’re amazing athletes.” https://www.the-scientist.com/news-opinion/bar-headed-geese-slow-their-metabolism-to-soar-over-everest-66386 https://www.the-scientist.com/news-opinion/bar-headed-geese-...
  - jhgb 5y ago
    The mountain range may have been significantly less tall back then but I'm quite sure it had already existed before any species of geese appeared.
- gerdesj 5y ago
  It wasn't that particular species at the time but a precursor. Your grandad is/was hom. sap. sap. but your (50,000,000 / 20)th grandad was one of quite a few possibilities, mostly ape and no sign of homo. I'm using a simple 20 year per generation model here. That's 2,500,000 generations ago. Here in the UK on telly, a comedian was shown how his (2021 - 1239) / 20 = 39 or so generational ancestor was English King Edward I - "longshanks". 39 generations gets you to 1230 or so, 2,500,000 generations is quite a long time ago. So, let's look at these geese. 50M years back, the "dinosaurs" flying that route - let's call them "Goosey" - already had phenomenally efficient lungs compared to say mammals. As the land rose, they simply adapted a bit. Given how efficient their lungs are I doubt there was much to do. It looks miraculous to us but we don't have those lungs. We didn't evolve the double ended lungs and hollow bones etc because we simply didn't need them or the cost of some part of that mix was detrimental for our use case or "we" simply rolled a double three. Evolution is weird. Well, no it isn't, that implies a blind watchmaker/intelligent design or nonsense as I prefer to call it. In the words of a famous bloke: "Evolution is as evolution does". No more and no less. There are some geese that are able to fly over some mountains.
  - 5y ago

smegcicle 5y ago

tldr bird respiratory system is very effective, they breathe in one end of their lungs and out the other, always with either a full breath in their lungs or two breaths in their air sacs (one fresh, one ready to be exhaled) http://www.lslbo.org/wp-content/uploads/2018/10/bird-lungs.jpg http://www.lslbo.org/wp-content/uploads/2018/10/bird-lungs.j...

Mountain_Skies 5y ago
We already have artificial continuous flow hearts, next up: continuous flow lungs.
- polishdude20 5y ago
  Like a literal jet engine. Continuous flow of air
  - redis_mlc 5y ago
    1) jet engines are interesting because of the continuous flow and also that all the rotating parts rotate in the same direction, a huge advantage over reciprocating engines. So jet engines can do 50,000 rps, while piston under 20,000 rps. Note that sleeve piston engines like the Rolls Royce Crecy, are much more efficient than valves, but development stopped at the end of WW2 and resources focused on jet engines. Rolls Royce Crecy - The Most Advanced Piston Aero Engine Never Made https://www.youtube.com/watch?v=cxK_zWgw6gY https://www.youtube.com/watch?v=cxK_zWgw6gY 2) the exception to continuous flow is the WW2 V-1 pulsejet engine, which has a gate that is closed at combustion time, about 42 Hz. The pulsejet is a very interesting engine in that it's the simplest possible jet engine - literally an empty metal tube with spray nozzles and a sparkplug. The V-1 was the first mass-produced cruise missile. The Germans also had air-to-ground (anti-ship) guided missiles both wire-guided and radio-guided with a TV screen(!) But the US Navy was the first to build precision-guided autonomous missiles, both the all-analog Sidewinder and Wall-eye, which shared modules. The Wall-eye made the famous Gulf War photos you've seen of entering via windows. It had analog circuitry to do edge-detection in real-time.

simorley 5y ago

So that's what dinosaur tastes like.

ARandomerDude 5y ago

It's not a question of where he grips it! It's a simple question of weight ratios! A five-ounce bird could not carry a one-pound coconut.

icelancer 5y ago
African swallows are non-migratory, man.

dang 5y ago

One past thread: Why Birds Can Fly over Mount Everest - https://news.ycombinator.com/item?id=23639294 https://news.ycombinator.com/item?id=23639294 - June 2020 (96 comments)

aspectmin 5y ago

I love reading both Nautilus and Quanta. Great articles.

m463 5y ago

an interesting thing is that though birds have super-efficient lungs, they can be very fragile. As any parrot owner knows, if you overheat a teflon pan, all the birds inside your house will die. So bird owners use stainless steel. There are other non-stick pans available, but it's really hard to wade through the marketing to figure out if overheating will kill the pet that's been in your family for years or even decades. unrelated, the name of this article made me wonder if it was about thin air and lift, thinking how helicopters can't fly over everest. But a mountain like everest might have a huge amount of updrafts to lift birds into the sky. If you've ever stopped at an ridge overlook along california highway 1, you might see something curious. the ridges are bird-superhighways. the ocean air hits the cliffs and deflects upwards, and this updraft lets birds "surf" up and down the coast. So if you stand there and are patient, you'll see lines of gulls cruise by going north or south without flapping.

deckard1 5y ago
efficiency and fragility seem to go together (see our current global container shipping fiasco and our just-in-time production world) The life at the deepest points of the ocean also seem quite fragile. Also, "canary in the coal mine". Canaries were sent into coal mines to detect carbon monoxide and other gases because they were more sensitive than humans. The bird would die before humans, giving an early warning.
photonic37 5y ago
If you’re in the Bay Area, you can stop by Fort Funston and see humans using this effect as well. In the hang gliding world, ridge lift is a wonderful phenomenon that enables one to stay airborne almost indefinitely, with much better predictability than thermal soaring. The lift band is well defined by the incoming wind and upward deflection. When you’re done, just turn inland and exit the lift band.
- ofcrpls 5y ago
  Same thing at Torrey Pines, if you are in San Diego.
5y ago

blacklight 5y ago

The author seems to pinpoint the cause of the great Permian-Triassic extinction to the acquired ability of microorganisms to process lignin, while most of the researchers attribute it to the extensive Siberian Traps eruptions. Granted, decaying lignin subtracts oxygen from the atmosphere, but had that happened alone the levels of oxygen would have gone down quite slowly. What we see instead is a drop from ~30% to 12% within a few hundreds of thousands of years. It means that a catastrophic event (such as prolonged supervolcanic eruptions) probably played a bigger role.

kashkhan 5y ago
Even if you converted all the atmospheric CO2 to O2, oxygen levels will not increase by more than 1%. So where did the rest come from and go to?
- rsj_hn 5y ago
  It came from CO2 and other carbon gasses. IIRC, according to current theory, there were 3 major climates in the earth. In the first climate, the atmosphere was volcanic gasses, many of which were blown off into space, leaving the second climate of carbon gases as a residue, and then this was absorbed into rocks as well as consumed by CO2 breathing lifeforms. https://www.nature.com/scitable/knowledge/library/earth-s-earliest-climate-24206248/ https://www.nature.com/scitable/knowledge/library/earth-s-ea...

jonnycomputer 5y ago

has the lignin story held up though? Wikipedia's article on Coal suggests that a 2016 paper "refuted" the idea. I don't really follow this area of research, so would be happy if someone more knowledgeable chimed in about it.