The idea is the same as the History Trivia Thread with Timmy (24 hr) and Modified Yi (no questions within own field) but questions about science. Chemistry, Biology, Physics, Engineering and Mathematics are included. Other fields might be included.
I'm a bit curious about the interest. But I'll start.
"Beavers change their circadian rhythm during the winter. What is special about that change?"
They stop waxing?
:lmfao:
I thought beavers, like bears, slept trough the winter...
I'd have to know what a Circadian rhythm is.
Biology is definitely not my field. :blush:
Quote from: HisMajestyBOB on November 10, 2009, 02:46:53 AM
I'd have to know what a Circadian rhythm is.
Biology is definitely not my field. :blush:
It's the daily cycle of living organisms.
No clue about the beavers. They go from being active at night to being active at day?
Quote from: Alatriste on November 10, 2009, 02:43:09 AM
I thought beavers, like bears, slept trough the winter...
This is sort of relevant, beavers do sit in their homes in the winter, but they do not hibernate. They still have waking and sleeping hours.
Quote from: The Larch on November 10, 2009, 05:17:56 AM
It's the daily cycle of living organisms.
No clue about the beavers. They go from being active at night to being active at day?
Yes, it is the daily cycle. But you answer is not correct.
Hint: They stay inside or under ice during the winter. And thus don't see the sky at all. The Sun usually sets the daily rhythm of most species.
It is based on temperature fluctuations rather than sunlight fluctuations?
Quote from: Caliga on November 10, 2009, 08:07:40 AM
It is based on temperature fluctuations rather than sunlight fluctuations?
Almost certainly not.
Edit: as temperature is almost certainly based on sunlight as well.
This is a good idea. To bad I suck at Science. :(
Tidal fluctuations?
It's based on the behavior of their prey? i.e., when the fish they eat are active, they're active, and when they're not, they sleep?
EDIT: I like Cal's answer. That makes more sense.
Quote from: HisMajestyBOB on November 10, 2009, 09:53:31 AM
It's based on the behavior of their prey? i.e., when the fish they eat are active, they're active, and when they're not, they sleep?
EDIT: I like Cal's answer. That makes more sense.
Beavers don't eat fish.
Quote from: Caliga on November 10, 2009, 09:52:52 AM
Tidal fluctuations?
No tidal effects on small freshwater dammed rivers.
It has to do with when the entrances to their dens freeze over or not?
Quote from: Caliga on November 10, 2009, 10:13:57 AM
It has to do with when the entrances to their dens freeze over or not?
The entrances usually don't freeze, but the dam lake does, so they can access the water under the ice. But as I said before, they cannot see the sun and they almost never leave the den.
They can detect humidity levels?
Viking is leading you guys astray.
Quote from: Grey Fox on November 10, 2009, 10:59:40 AM
Viking is leading you guys astray.
;)
But I'm being honest. I didn't ask why it changed, I asked what is special about the change.
It is unique in the animal kingdom?
I thought special meant interesting. It wasn't very interesting when I looked it up.
The cycles get longer?
Is it that they continue to operate without cues to reorient them, at least until summer? (i doubt that)
Or maybe that they are oriented by some other species?
Quote from: Maximus on November 10, 2009, 11:13:59 AM
The cycles get longer?
Yes, during the winter when the Beavers are in the dens they end up with a daily cycle 29 hours long.
You got it. Quote from: Caliga on November 10, 2009, 11:07:14 AM
It is unique in the animal kingdom?
I don't know if it is unique. I don't know of any other species which does it and I don't know of any other species which moves underground and stays awake for a season.
Quote from: Viking on November 10, 2009, 11:19:35 AM
I don't know if it is unique. I don't know of any other species which does it and I don't know of any other species which moves underground and stays awake for a season.
As far as I know this happens with all animals if you keep them in the dark long enough. The circadian rhythm becomes untethered as it were.
Quote from: Viking on November 10, 2009, 11:19:35 AM
I don't know if it is unique. I don't know of any other species which does it and I don't know of any other species which moves underground and stays awake for a season.
I believe I've read that humans do the same thing when denied light cycles.
Interesting idea- could this be an indication that the earth's rotation used to be slower?
Quote from: garbon on November 10, 2009, 11:21:55 AM
Quote from: Viking on November 10, 2009, 11:19:35 AM
I don't know if it is unique. I don't know of any other species which does it and I don't know of any other species which moves underground and stays awake for a season.
As far as I know this happens with all animals if you keep them in the dark long enough. The circadian rhythm becomes untethered as it were.
But then maybe the trick is that they synchronize with each other?
I think humans have an average cycle absent of cues of about 25 hours, but without cues humans will end up on radically different schedules.
Quote from: Maximus on November 10, 2009, 11:24:48 AM
Interesting idea- could this be an indication that the earth's rotation used to be slower?
No--I think it is slowing down.
Earth's rotation is slowing down, not speeding up.
Is it possible though that some event in the past caused it to speed up? An asteroid impact, for example, or near miss.
Anyway, below is a crystal of the metal with the highest diamagnetic property. What element is it?
(https://languish.org/forums/proxy.php?request=http%3A%2F%2Fi79.photobucket.com%2Falbums%2Fj143%2Ftheroguester%2Fcrystal.jpg&hash=fa588ac3251b0035304c8cf75e0cc38ac4db3510)
Titanium?
nope
Quote from: Maximus on November 10, 2009, 11:32:01 AM
Is it possible though that some event in the past caused it to speed up? An asteroid impact, for example, or near miss.
Someone can jump in if I'm wrong, but orbiting bodies tend to slow down their rotation and synch with the body they are orbiting. That is why there is a dark side of the moon--the moon has fully synched up and no longer rotates--thus there is only one side that faces us.
For an asteroid collision to change our rotation that much, I'm guessing it would result in the total extinction of any life larger than a few cells.
Fuck it's even a geology question and I can't get it. I can't even remember what diamagnetic means.
Let's guess the obvious - iron (although I can't recall ever seeing an iron crystal before)?
Silver?
Quote from: alfred russel on November 10, 2009, 11:44:44 AM
Quote from: Maximus on November 10, 2009, 11:32:01 AM
Is it possible though that some event in the past caused it to speed up? An asteroid impact, for example, or near miss.
For an asteroid collision to change our rotation that much, I'm guessing it would result in the total extinction of any life larger than a few cells.
yea probably. Was just a thought.
Quote from: Barrister on November 10, 2009, 11:45:56 AM
Fuck it's even a geology question and I can't get it. I can't even remember what diamagnetic means.
Let's guess the obvious - iron (although I can't recall ever seeing an iron crystal before)?
Nope, iron is ferromagnetic.
QuoteSilver?
nope
Vanadium?
Bismuth?
Damn, that's an hard question.
What's the difference between ferro & dia magnetic?
Carbon?
Quote from: Viking on November 10, 2009, 11:55:29 AM
Bismuth?
Correct.
In simple terms, a ferromagnetic material is attracted by magnets, a diamagnetic material is repelled.
Quote from: Grey Fox on November 10, 2009, 11:55:54 AM
Damn, that's an hard question.
What's the difference between ferro & dia magnetic?
Ferromagnetism means that the magnetic field is set by the structure of the material. Basically normal magnets.
Diamagnetism means that the material gives off a magnetic field opposite to the field acting on it.
By the way, the human body is diamagnetic. Given a powerful enough magnetic field and the right conditions you could levitate on it.
Of course no telling what else that level of energy would do to you.
Kelvin came up in another thread. Kelvin didn't know about fusion and thus got the age of the sun very very wrong by calculating it's age based on it's temperature. Kelvin tried the same with the earth but despite no fusion happening on earth he got that wrong as well. This is from a period in Lord Kelvin's life where he made himself famous for getting stuff wrong, rather than an earlier part where he made his much deserved reputation.
Name one of the two main causes of error in Kelvins estimation of the age of the earth.
Quote from: Maximus on November 10, 2009, 12:06:14 PM
By the way, the human body is diamagnetic. Given a powerful enough magnetic field and the right conditions you could levitate on it.
Of course no telling what else that level of energy would do to you.
Meh, Nerds and their levitating tadpoles.
Quote from: Viking on November 10, 2009, 12:11:27 PM
Kelvin came up in another thread. Kelvin didn't know about fusion and thus got the age of the sun very very wrong by calculating it's age based on it's temperature. Kelvin tried the same with the earth but despite no fusion happening on earth he got that wrong as well. This is from a period in Lord Kelvin's life where he made himself famous for getting stuff wrong, rather than an earlier part where he made his much deserved reputation.
Name one of the two main causes of error in Kelvins estimation of the age of the earth.
Not accounting for radioactive decay generating heat?
Quote from: Viking on November 10, 2009, 12:11:27 PM
Kelvin came up in another thread. Kelvin didn't know about fusion and thus got the age of the sun very very wrong by calculating it's age based on it's temperature. Kelvin tried the same with the earth but despite no fusion happening on earth he got that wrong as well. This is from a period in Lord Kelvin's life where he made himself famous for getting stuff wrong, rather than an earlier part where he made his much deserved reputation.
Name one of the two main causes of error in Kelvins estimation of the age of the earth.
He thought geothermal activity was caused by chemical reactions?
Quote from: Barrister on November 10, 2009, 12:13:40 PM
Quote from: Viking on November 10, 2009, 12:11:27 PM
Kelvin came up in another thread. Kelvin didn't know about fusion and thus got the age of the sun very very wrong by calculating it's age based on it's temperature. Kelvin tried the same with the earth but despite no fusion happening on earth he got that wrong as well. This is from a period in Lord Kelvin's life where he made himself famous for getting stuff wrong, rather than an earlier part where he made his much deserved reputation.
Name one of the two main causes of error in Kelvins estimation of the age of the earth.
Not accounting for radioactive decay generating heat?
That is one, the other is that he didn't know about the mantle and it's effects on convection in the core.
Quote from: Maximus on November 10, 2009, 12:15:50 PM
He thought geothermal activity was caused by chemical reactions?
Kelvin assumed a molten ball of earthstuff and calculated how long it would take to cool down to the present temperature. He assumed more efficient convection and did not include heat from radioactive decay. Kelvin probably understood heat better than any person in his own lifetime, so don't assume he was stupid. He just lacked information.
I've got about 10 minutes before leaving for court - let me see what I can come up with.
Quote from: Viking on November 10, 2009, 12:23:15 PM
Kelvin assumed a molten ball of earthstuff and calculated how long it would take to cool down to the present temperature. He assumed more efficient convection and did not include heat from radioactive decay. Kelvin probably understood heat better than any person in his own lifetime, so don't assume he was stupid. He just lacked information.
I wasn't assuming he was stupid. Verne wasn't stupid either, but he subscribed to that theory.
Extremely simple (if you've taken geology 101 that is), but I want to keep things moving:
The most common mineral containing lead is called Galena (formula: PbS). What is the obvious visual feature about Galena crystals that makes it easy to identify?
Quote from: Barrister on November 10, 2009, 12:30:59 PM
Extremely simple (if you've taken geology 101 that is), but I want to keep things moving:
The most common mineral containing lead is called Galena (formula: PbS). What is the obvious visual feature about Galena crystals that makes it easy to identify?
They are yellow?
Quote from: Viking on November 10, 2009, 12:36:20 PM
Quote from: Barrister on November 10, 2009, 12:30:59 PM
Extremely simple (if you've taken geology 101 that is), but I want to keep things moving:
The most common mineral containing lead is called Galena (formula: PbS). What is the obvious visual feature about Galena crystals that makes it easy to identify?
They are yellow?
Nope.
Wasn't there some kind of Yi rule used for this thread?
The modified Yi rule here is about your own field. There is no science in Law, so Beeb can ask anything he wants.
The crystal split cleanly so it has flat surfaces where it has been broken?
Quote from: Viking on November 10, 2009, 12:55:25 PM
The modified Yi rule here is about your own field. There is no science in Law, so Beeb can ask anything he wants.
He has some kind of degree in geology, though, IIRC.
Quote from: The Larch on November 10, 2009, 12:52:34 PM
Wasn't there some kind of Yi rule used for this thread?
Undergrad was in geology, but clearly not my profession so I thought this would be okay. Besides galena really is Geology 101.
They have a sweet flavor?
Quote from: Caliga on November 10, 2009, 03:45:46 PM
They have a sweet flavor?
"Lead: delicious but deadly!"
Quote from: Malthus on November 10, 2009, 03:47:14 PM
"Lead: delicious but deadly!"
Seriously. -_- Didn't the Romans sweeten food with lead powder?
Quote from: Barrister on November 10, 2009, 12:30:59 PM
Extremely simple (if you've taken geology 101 that is), but I want to keep things moving:
The most common mineral containing lead is called Galena (formula: PbS). What is the obvious visual feature about Galena crystals that makes it easy to identify?
They are grey?
Quote from: frunk on November 10, 2009, 11:28:24 AM
Earth's rotation is slowing down, not speeding up.
I recommend that we destroy the moon in order to preserve our precious angular momentum.
Quote from: Neil on November 10, 2009, 04:15:02 PM
Quote from: frunk on November 10, 2009, 11:28:24 AM
Earth's rotation is slowing down, not speeding up.
I recommend that we destroy the moon in order to preserve our precious angular momentum.
Wouldn't we also have to destroy the sun?
Quote from: Lucidor on November 10, 2009, 03:59:36 PM
Quote from: Barrister on November 10, 2009, 12:30:59 PM
Extremely simple (if you've taken geology 101 that is), but I want to keep things moving:
The most common mineral containing lead is called Galena (formula: PbS). What is the obvious visual feature about Galena crystals that makes it easy to identify?
They are grey?
That can't be it. There are lots of grey minerals.
Quote from: Barrister on November 10, 2009, 12:30:59 PM
Extremely simple (if you've taken geology 101 that is), but I want to keep things moving:
The most common mineral containing lead is called Galena (formula: PbS). What is the obvious visual feature about Galena crystals that makes it easy to identify?
It's mineral structure is a perfect cube, so when formed under ideal conditions you have these perfect little D6 shapes.
Okay, so no geology, how about atsronomy. Again, going for easy:
Saturn has a total of 38 moons (according to Wiki). Name seven of them, without getting any wrong. That is you must name only 7 names, and all seven must be moons of Saturn.
Quote from: alfred russel on November 10, 2009, 04:21:32 PM
Quote from: Neil on November 10, 2009, 04:15:02 PM
Quote from: frunk on November 10, 2009, 11:28:24 AM
Earth's rotation is slowing down, not speeding up.
I recommend that we destroy the moon in order to preserve our precious angular momentum.
Wouldn't we also have to destroy the sun?
I'm pretty sure that the Earth actually gains angular momentum from the Sun from tidal interaction, just as the moon does from the Earth.
Quote from: Barrister on November 10, 2009, 04:29:52 PM
Quote from: Barrister on November 10, 2009, 12:30:59 PM
Extremely simple (if you've taken geology 101 that is), but I want to keep things moving:
The most common mineral containing lead is called Galena (formula: PbS). What is the obvious visual feature about Galena crystals that makes it easy to identify?
It's mineral structure is a perfect cube, so when formed under ideal conditions you have these perfect little D6 shapes.
Okay, so no geology, how about atsronomy. Again, going for easy:
Saturn has a total of 38 moons (according to Wiki). Name seven of them, without getting any wrong. That is you must name only 7 names, and all seven must be moons of Saturn.
Titan, Phoebe, Iapetus, Rhea, Mimas, Tethys, Prometheus.
Quote from: Neil on November 10, 2009, 04:33:22 PM
Titan, Phoebe, Iapetus, Rhea, Mimas, Tethys, Prometheus.
I had to double check on Prometheus.
You've got it.
Quote from: Neil on November 10, 2009, 04:30:32 PM
Quote from: alfred russel on November 10, 2009, 04:21:32 PM
Quote from: Neil on November 10, 2009, 04:15:02 PM
Quote from: frunk on November 10, 2009, 11:28:24 AM
Earth's rotation is slowing down, not speeding up.
I recommend that we destroy the moon in order to preserve our precious angular momentum.
Wouldn't we also have to destroy the sun?
I'm pretty sure that the Earth actually gains angular momentum from the Sun from tidal interaction, just as the moon does from the Earth.
Eventually the earth will slow down so that only one side faces the sun, just like how the moon is with the earth.
I think.
Quote from: Neil on November 10, 2009, 04:30:32 PM
I'm pretty sure that the Earth actually gains angular momentum from the Sun from tidal interaction, just as the moon does from the Earth.
How do you figure?
Wouldn't the tidal system tend toward entropy? Seems resistance to the tidal flow would be slowing us down, not speeding us up.
The best plan is to set up gigantic solar sails that would spin the earth faster.
Quote from: frunk on November 10, 2009, 05:57:20 PM
The best plan is to set up gigantic solar sails that would spin the earth faster.
How about if we all ran real fast due west?
Quote from: Admiral Yi on November 10, 2009, 05:59:09 PM
How about if we all ran real fast due west?
That might work as long as we constantly accelerated.
Quote from: Maximus on November 10, 2009, 05:09:53 PM
Quote from: Neil on November 10, 2009, 04:30:32 PM
I'm pretty sure that the Earth actually gains angular momentum from the Sun from tidal interaction, just as the moon does from the Earth.
How do you figure?
Wouldn't the tidal system tend toward entropy? Seems resistance to the tidal flow would be slowing us down, not speeding us up.
The angular momentum we steal from the sun increases our orbit rather than accelerating our spin. It is thus conserved.
Neil you need to post a question.
Quote from: Admiral Yi on November 10, 2009, 05:59:09 PM
Quote from: frunk on November 10, 2009, 05:57:20 PM
The best plan is to set up gigantic solar sails that would spin the earth faster.
How about if we all ran real fast due west?
Not enough mass. Humanity only masses roughly 560 teragrams, whereas the Earth masses 5,900 yottagrams. Better to use a large asteroid like Psyche or Juno, which mass about 25 zettagrams.
Quote from: Barrister on November 10, 2009, 07:39:21 PM
Neil you need to post a question.
Really? I hate posting questions.
What is the name of the alleged giant impactor that is believed to have caused the formation of Earth's moon?
Quote from: Neil on November 10, 2009, 07:47:53 PM
Not enough mass. Humanity only masses roughly 560 teragrams, whereas the Earth masses 5,900 yottagrams. Better to use a large asteroid like Psyche or Juno, which mass about 25 zettagrams.
We stampede all our cattle due west at the same time. :)
Quote from: Admiral Yi on November 10, 2009, 07:51:47 PM
Quote from: Neil on November 10, 2009, 07:47:53 PM
Not enough mass. Humanity only masses roughly 560 teragrams, whereas the Earth masses 5,900 yottagrams. Better to use a large asteroid like Psyche or Juno, which mass about 25 zettagrams.
We stampede all our cattle due west at the same time. :)
The total mass of the biosphere is in the exagram range. Even if it were possible, it wouldn't be helpful, and couldn't be maintained in any event.
Quote from: Neil on November 10, 2009, 08:01:23 PM
The total mass of the biosphere is in the exagram range. Even if it were possible, it wouldn't be helpful, and couldn't be maintained in any event.
Why do you hate
America Canada Alberta? :(
Quote from: Peter Wiggin on November 10, 2009, 08:09:37 PM
Quote from: Neil on November 10, 2009, 08:01:23 PM
The total mass of the biosphere is in the exagram range. Even if it were possible, it wouldn't be helpful, and couldn't be maintained in any event.
Why do you hate America Canada Alberta? :(
Because they are so much less than I am.
Ah, weight issues. :console:
Quote from: Neil on November 10, 2009, 07:49:54 PM
Quote from: Barrister on November 10, 2009, 07:39:21 PM
Neil you need to post a question.
Really? I hate posting questions.
What is the name of the alleged giant impactor that is believed to have caused the formation of Earth's moon?
Jo-Jo.
Quote from: Neil on November 10, 2009, 07:49:54 PM
Quote from: Barrister on November 10, 2009, 07:39:21 PM
Neil you need to post a question.
Really? I hate posting questions.
What is the name of the alleged giant impactor that is believed to have caused the formation of Earth's moon?
Something silly from mythology.
Nemesis?
Selene?
The day fake-Mars crashed into Earth?
V'ger?
Nobody has it yet.
I surrendered and googled it.. I could not have guessed that in a thousand tries.
Jaron
Bump. Nobody got it, so Neil ask again or open the floor.
The floor is open.
A really nasty chemical is often used in gold mining. What is the chemical and why is it used?
The first thing that popped into my head is arsenic, don't remember why except maybe it forms an alloy with the other elements and leaves gold alone.
Quote from: frunk on November 16, 2009, 06:01:31 PM
The first thing that popped into my head is arsenic, don't remember why except maybe it forms an alloy with the other elements and leaves gold alone.
I'm pretty sure that's basically it.
Quote from: frunk on November 16, 2009, 06:01:31 PM
The first thing that popped into my head is arsenic, don't remember why except maybe it forms an alloy with the other elements and leaves gold alone.
Arsenic is common in gold bearing ores, so it is often associated with gold, but it is not used in the process.
Quote from: Viking on November 16, 2009, 05:57:45 PM
A really nasty chemical is often used in gold mining. What is the chemical and why is it used?
Greed.
And if not greed then cyanide.
edit: it is used to separate the gold from the base metals and rock.
Quote from: crazy canuck on November 16, 2009, 06:09:08 PM
Quote from: Viking on November 16, 2009, 05:57:45 PM
A really nasty chemical is often used in gold mining. What is the chemical and why is it used?
Greed.
And if not greed then cyanide.
And how is cyanide used?
Cyanide. It forms a solution with gold so that gold can be extracting from fine particles of ore more easily.
CC got it first so he gets the floor.
For what work did Einstein get his Nobel prize in 1921?
Quote from: crazy canuck on November 16, 2009, 06:38:15 PM
For what work did Einstein get his Nobel prize in 1921?
I know what he didn't get it for... I just can't remember what he got it for. :(
His tireless campaign to impeach Bush.
Quote from: Viking on November 16, 2009, 06:39:54 PM
Quote from: crazy canuck on November 16, 2009, 06:38:15 PM
For what work did Einstein get his Nobel prize in 1921?
I know what he didn't get it for... I just can't remember what he got it for. :(
Its a lot more difficult then it sounds at first.
edit: My grade 7 son got me with this one....
Quote from: crazy canuck on November 16, 2009, 06:45:08 PM
Quote from: Viking on November 16, 2009, 06:39:54 PM
Quote from: crazy canuck on November 16, 2009, 06:38:15 PM
For what work did Einstein get his Nobel prize in 1921?
I know what he didn't get it for... I just can't remember what he got it for. :(
Its a lot more difficult then it sounds at first.
edit: My grade 7 son got me with this one....
It's a bit like J.R.R. Tolkein getting the Literature Prize for The Silmarillon.
Photoelectric effect.
Or maybe that was earlier. I don't know if he won just 1 or 2.
Quote from: HisMajestyBOB on November 16, 2009, 06:53:32 PM
Photoelectric effect.
Or maybe that was earlier. I don't know if he won just 1 or 2.
ding ding ding.
And it was that work that got him thinking about relativity and the rest is history.
Easy question for astronomy nerds:
As a supergiant star nears the end of it's lifespan, it begins burning denser and denser fuels in it's core through nuclear fusion. Eventually it ends up with an element that cannot be used in a fusion reaction (it requires more energy than it gives off); without the heat generated from the fusion reaction, the core collapses, creating either a neutron star or, if the star is massive enough, a black hole.
What is the last element present in the star's core, and approximately how long is it from the element's first appearance to the core's collapse?
Iron and dunno.
Yes to Iron (wiki says it's actually Nickel that decays into Iron, but every other source I've seen says Iron, so FU wikipedia).
Hint on the length: each successive element burning process takes much less time than the previous one. Hydrogen takes 10s of millions of years, depending on the star's mass (bigger is shorter); helium is just millions of years; carbon is 1000s of years...
Quote from: HisMajestyBOB on November 16, 2009, 08:30:56 PM
Yes to Iron (wiki says it's actually Nickel that decays into Iron, but every other source I've seen says Iron, so FU wikipedia).
Hint on the length: each successive element burning process takes much less time than the previous one. Hydrogen takes 10s of millions of years, depending on the star's mass (bigger is shorter); helium is just millions of years; carbon is 1000s of years...
Sounds like it's going to be something on the other of 10^-lots seconds.
Not quite that short. It's a long time to go without food, but a short time for a vacation.
Quote from: HisMajestyBOB on November 16, 2009, 09:12:20 PM
Not quite that short. It's a long time to go without food, but a short time for a vacation.
It also varies somewhat based on the mass of the star, although not tremendously.
two days?
Close enough. It's about 3-5 days for your typical supergiant star (~20 solar masses). As Neil stated, larger stars burn faster, smaller ones burn slower.
Ulmont got the iron, Viking got the time, so you two can duke it out.
Viking can call it.
When women spend a lot of time together they synchronise their ovulation. Question: What do the women synchronise their rhythm to? and bonus points for What will prevent the synchronisation?
(assume a group of hunter gatherers, not a group of women in modern society)
The moon and dwelling in a cave away from the stars?
Quote from: ulmont on November 16, 2009, 10:50:19 PM
The moon and dwelling in a cave away from the stars?
nope, neither
Quote from: ulmont on November 16, 2009, 10:50:19 PM
The moon and dwelling in a cave away from the stars?
Although wiki says the synchronization appears to be bullshit, undercutting the premise of the question...
Wiki says a lot of things.
I'm guessing pregnancy will prevent the synchronization. Or menopause.
The phases of the moon was my guess... do they synchronize to the woman with the shortest cycle?
Quote from: HisMajestyBOB on November 16, 2009, 11:02:47 PM
Wiki says a lot of things.
Including iron, if you dig into the article a little further. http://en.wikipedia.org/wiki/Star#Nuclear_fusion_reaction_pathways
This article says Nickel: http://en.wikipedia.org/wiki/Type_II_supernova
:lol:
Quote from: HisMajestyBOB on November 16, 2009, 11:09:23 PM
This article says Nickel: http://en.wikipedia.org/wiki/Type_II_supernova
From the article:
QuoteThe star evolves to accommodate the fusion of these accumulating, higher mass elements, until finally a core of iron is produced. However, the nuclear fusion of iron produces no net energy to sustain the star, so the core becomes an inert mass that is supported only by the degeneracy pressure of electrons
:huh:
The chart, partway down.
Okay, I admit I didn't actually try to read the article. I've seen my students write better.
Quote from: HisMajestyBOB on November 16, 2009, 11:02:47 PM
Wiki says a lot of things.
I'm guessing pregnancy will prevent the synchronization. Or menopause.
The phases of the moon was my guess... do they synchronize to the woman with the shortest cycle?
I sort of assumed that menopause and pregnancy were obvious non answers.
No, they do not synchronize to the woman with the shortest cycle.
Quote from: Viking on November 16, 2009, 11:23:34 PM
No, they do not synchronize to the woman with the shortest cycle.
(https://languish.org/forums/proxy.php?request=http%3A%2F%2Ffarm4.static.flickr.com%2F3643%2F3562300974_51bd7ed300.jpg&hash=7bb50e0d7a22d5941312fda3136f34eb4b4ff28a)
?
The alpha female?
I'm curious to know the answer.
Quote from: Admiral Yi on November 17, 2009, 04:24:49 PM
The alpha female?
I'm curious to know the answer.
Yes, they will synchronise to the dominant female, unless they are having regular sex, in which case it will be completely out of whack.
Well shit.
I don't have a question. The floor is as open as the Rub al-Khali.
Quote from: Admiral Yi on November 17, 2009, 04:59:16 PM
Well shit.
I don't have a question. The floor is as open as the Rub al-Khali.
Right now I'm listening to a podcast discussing science education in Texas. Stand up for your country!!
:punk:
Name a species of land animal besides homo sapien that sheds salt tears.
Quote from: Admiral Yi on November 17, 2009, 05:14:06 PM
:punk:
Name a species of land animal besides homo sapien that sheds salt tears.
Pigs?
No.
Full disclosure: I read this factoid about 600 years ago, back when grumbler was middle aged; there is one species the author mentioned which I distinctly remember, there's a remote possibility the author mentioned another which I have forgotten.
Do you mean elephants, as in emotional tears? I thought most mammals could produce tears, which contain salt.
Reptiles and birds produce salty tears, usually only marine mammals produce salty tears. All animals with eyes produce tears.
Dogs?
Quote from: frunk on November 17, 2009, 05:44:48 PM
Do you mean elephants, as in emotional tears? I thought most mammals could produce tears, which contain salt.
Elephants was what I was looking for.
According to my book (The Descent of Woman) humans and elephants (and one more?) are the only land animals whose tears contain salt. The author's theory was that humans (and elephants (and one more??)) adapted to the billion year drought in Africa by going part way toward becoming amphibians, then changing back when the drought ended. Salt tears are very common in amphibians and sea birds, to regulate the body's salt level.
Regardless, the baton is in your hands.
edit: Right, might have been mammals Viking. Still, no harm done.
What significant fact about horses moving did Eadweard Muybridge prove?
One hoof is always touching the ground?
Nope.
Quote from: Admiral Yi on November 17, 2009, 05:51:13 PM
Quote from: frunk on November 17, 2009, 05:44:48 PM
Do you mean elephants, as in emotional tears? I thought most mammals could produce tears, which contain salt.
Elephants was what I was looking for.
According to my book (The Descent of Woman) humans and elephants (and one more?) are the only land animals whose tears contain salt. The author's theory was that humans (and elephants (and one more??)) adapted to the billion year drought in Africa by going part way toward becoming amphibians, then changing back when the drought ended. Salt tears are very common in amphibians and sea birds, to regulate the body's salt level.
Regardless, the baton is in your hands.
edit: Right, might have been mammals Viking. Still, no harm done.
The Author of Decent of Woman is Elaine Morgan. She has no credentials and she has been advancing what is called the Aquatic Ape Hypothesis for 30 years now. It is wrong. The main problem is that our salt glands do not work the same way as marine mammals, they work like the salt glands of birds.
Here is a site which goes into this in some detail.
Quote from: http://www.aquaticape.org/Salt glands
In the section on tears you'll find that AAT/H proponents claim tears in humans are a method of actively excreting salt in response to a saltwater environment, but in fact, tears are never hypertonic and cannot do what AAT/H proponents claim for them. Tears are, however, strongly hypertonic in regard to potassium and that does indicate what environment we developed in. That environment is terrestrial, not aquatic. The salt glands of terrestrial birds and reptiles are specialized for excreting potassium, unlike those of their marine relatives.
Some AAT/H proponents, most notably Elaine Morgan, have insisted that salt glands do not exist in terrestrial birds and reptiles. I must admit I find it discouraging that someone who is making up a theory with which they wish to supplant the past several decades of paleoanthropology does so little research before making such claims. This info is readily available.
Of course, it may be that it isn't simply poor research, since Morgan continued to make the "salt glands only in marine birds and reptiles" claim long after the facts (with refs and accurate quotes) had been presented to her (in several newsgroup posts which she replied to and so presumably read). She did finally say that she was dropping these bogus claims, but these are related to her claims that human tears and sweat are aquatic adaptations, and she and other AAT/H proponents still make those claims. As always, the "false facts" generated by AAT/H proponents are persistent, and so I feel the facts must be stated once again.
Are you sure you aren't talking about emotional tears rather than just salty fluid seeping from the eye socket?
Quote from: Admiral Yi on November 17, 2009, 06:00:46 PM
One hoof is always touching the ground?
Horses do lift all feet off the ground while galloping:contract:
He proved that the stride length was twice as long as the horse from nose to tail?
Quote from: Viking on November 17, 2009, 06:12:39 PM
Horses do lift all feet off the ground while galloping:contract:
He proved that the stride length was twice as long as the horse from nose to tail?
Your offhand comment is right, through the use of still photography he showed that horses do have all four hooves off the ground when galloping. This was despite his contrary expectation.
Just bumping up this thread.
Apparently the question was mine, and I let the thread die... so the next question is
"One Horsepower in a car is definitively not the average power of one horse, so how was the horsepower defined?"
The amount of energy required to pull one kilo up a 45% slope. Or something like that.
Quote from: Admiral Yi on January 29, 2010, 07:41:49 PM
The amount of energy required to pull one kilo up a 45% slope. Or something like that.
hint, the question is "how was" not "how is". Horsepower is not a nice little SI unit. This Unit predates SI or any other unit system.
It has something to do with horse teams pulling barges along British canals IIRC.