Humans are more dependent on water than many other mammals
scientificamerican.com
scientificamerican.com
This is just partly true, however, and I assume you don't mean that babies are natural born swimmers. :) Ref. Wikipedia; "Babies are not old enough to hold their breath intentionally or strong enough to keep their head above water, and cannot swim unassisted. Most infants, though not all, will reflexively hold their breath when submerged to protect their airway and are able to survive immersion in water for short periods of time." [0]
Shalow, warm, maybe even not salty water? It must have been significant food source if we have very specific adaptation to gipping something in water.
And we are unsure if that's a remnant of common ancestor or a parallel evolution.
This definitely shocked me. May as well ask me to sprout wings and fly!
That's the coolest thing since a friend showed me he could move his ears.
Or are you supposed to plug from the inside, with your tongue blocking the top of the mouth kind of ?
Whether air from both places actually goes into my lungs? That, I don't know. So you may be right in that regard? I really don't know. :)
[0]: https://freedivewire.com/wp-content/uploads/2016/11/frenzel....
Also, it doesn't work well now that I have a mustache.
Me: I wonder why our son doesn’t like to get his head wet in the bath or the pool.
Her: I think he doesn’t like to get water in his nose, like me.
Me: uh... what?
Her: blah blah blah
Me: WHAT DO YOU MEAN YOU CANNOT CLOSE YOUR NOSTRILS FROM THE INSIDE?!
Or something like that. I guess I assumed that everyone could just block it off from the inside. It’s apparently not something that comes up very often?
Me: picks up pencil with foot.
Wife: WTF?
Although I am guessing sealing nostrils from water versus from smell is distinct: I feel you can seal at the front “inside” the nostrils (think blocked nose) versus sealing at the back (soft palate?). Edit: Also when you blow your nose, i think you partially use the muscles that close off the nasal passages?
Although quite possibly I am misunderstanding something - we often struggle to even realise what we naturally do (e.g. when swimming) or struggle to understand that others do things differently.
I remember reading a news article about the tragic death of a young girl from this. It was at her birthday party. Her friends got her some MDMA, which she had never tried before, and she freaked out, locked herself in the bathroom, and drank an unbelievable amount of water. Her sodium levels tanked, her brain swelled, and she died.
As a tangent, the news article was titled something like "MDMA kills teen", as if the drug had poisoned her, rather than blaming ignorance and sodium depletion from drinking too much water.
One of the many sources of hysteria around drugs in that period of time, and from the wikipedia it looks like it wasn't just anti-drugs campainers who exploited the situation; alcohol companies fearing competition had a go too...
"If Leah had taken the drug alone, she might well have survived. If she had drunk the amount of water alone, she would have survived."
During Ramadan (not Eid as someone pointed out!), most Muslims refrain from eating or drinking during the day, and Muslims are highly overrepresented in warmer countries, so it's definitely possible, though maybe not comfortable.
During the lunar month of Ramadan. Eid is the first day of the following month when Muslims celebrate the end of Ramadan. (There is an unrelated separate Eid at a different point in the year).
Sort of, yes. During noon and afternoon most shops, restaurants, and other places were closed. Certain essential things were open. There was also a divide between rural vs urban, with urban have more open stores.
Especially in Morocco this didn't seem too uncommon even outside of Ramadan though as its often simply too hot to really work during the day.
Imagine two civilizations otherwise equal. One works 12/12=100% of the year, and the other 11.5/12=96% of the years. Then compound the gains over 14 centuries!
In practice there is probably plenty of inefficiencies to go around. Maybe less today, but 14 centuries ago.
e.g. here's a Facebook Post from IKEA Qatar on their store hours during Ramadan: https://m.facebook.com/IKEAQatar/photos/pb.577718508978609.-...
I did on some occasions on a hot day, before going off to some activity - and it does not last the whole day - but it definitely last some time.
But you are correct, that when you drink more and more, despite your body being already hydrated - then it pretty much comes out like it is soon after.
": Our findings agree with the long held notion that each gram of glycogen is stored in human muscle with at least 3 g of water. Higher ratios are possible (e.g., during REHFULL) likely due to water storage not bound to glycogen. "
If you want to store extra water for short periods drink/eat carbs
Sports drinks are generally water with sodium chloride and potassium chloride added, often with sugar as well. Trust me, if you're sweating a lot and drinking a lot of water, you need a source of the appropriate salts.
It’s seems like this is kind of related to where bikers (cyclists) pay double for a component to save 100 grams instead of losing a bit of body weight.
Perhaps they are hiking for extended distances without water where no matter how much you chug, it won't be enough?
Is kind of dumb argument. There is no tradeoff between the two. You can do both of these or neither. The additional weight in equipment will be there regardless of what happens to your bodyweight.
Sorry, but not bringing a bottle or a flask because of weight is known as Stupid Light. Yeah, you could probably do it, but it's stupid to do. Another example is using a keychain light as your only light. You could do it, but it's stupid to do, and if you end up in an emergency situation, you're going to get little sympathy for the team of rescuers that save your stupid light butt. These ideas are what happens when you are sitting and looking at a spreadsheet of gear weights in a far larger proportion then actually being out and seeing what actually works.
Getting lost on the trail, somebody getting injured, relying on water along the trail, just being sweatier than you expected, all of these end with somebody being very uncomfortable or worse.
Weight is costly (eg, mv^2 energy to accelerate). I guess human bodies have spent a lot of time trying to find the minimum amount of water necessary rather than trying to build up a reserve.
The little micro-optimisations add up over time. The penalty for excess weight doesn't have to be large before evolution tries to get rid of it. Historically, fat people are an anomaly.
I try to take a similar approach when hiking of drinking as much water as I can before starting a hike. In a hot and dry climate you don't end up urinating out as much as you might think.
Exposure to this practice over time in a particular environment might be able to alter gene expression to better support the practice much like the hunter reflex develops with cold exposure. People often make the mistake of thinking their personal modern experience is close to some human limit.
"The Old Way" also points out that persistence hunting (mentioned in this article) could only be used under particular environmental conditions (mud after rain that slows down animals) with a particular animal that overheats more than others so it didn't seem a reliable hunting method.
There is a myth on the internet that drinking shitload of water beyond comfort is acceptable and has zero risks because hey it’s just water right?
Here is some literature: https://www.scientificamerican.com/article/strange-but-true-...
In the article you point to the main issue seems to come from inhibition of urination. I think native people knew their bodies extremely well and could avoid any problem here whereas in modern times we have been training ourselves since being a small child to ignore or hold back urination. Combining that with other suppressors mentioned in that article can end in tragedy.
Because we have skills to maintain ourselves in advanced ways, the optimal answer was apparently to give us more problems to solve while liberating us from the drawbacks of built-in solutions.
What's up with needing water sugar and air, while creating waste product? Just use electricity.
It doesn’t sound very pleasant though…
As discussed a few months ago: https://news.ycombinator.com/item?id=26232597
If the reverse were true we wouldnt have hundreds of people a year dying on dingies trying to cross Mediterranean. Do you think they never tried drinking water around them?
And all the boards did shrink;
Water, water, every where,
Nor any drop to drink.
Why is saltwater such a hypothetical problem for them? How are ocean-going fish and shrimp "fresh water"? Those are going to be saltwater too.
If X has something generally harmful to animals, Y has likely evolved some mechanism to filter it or neutralize it.
Meat is impedance matching for the food chain.
Sea-dwelling creatures have different ways to deal with this. Most fish can "pump" salt from their blood into the water in their gills, in addition to their kidneys filtering salt.
The other strategy is to eat fish that have already done all that work, after all most animals are mostly water of compatible salt content.
(Freshwater fish have the opposite problem, without active salt management they would explode from osmosis drawing water into their cells).
There’s also the water heater if it has a tank - it can be drained from the bottom (you’ll want to shut it off if it’s not refilling).
But of course once you're dehydrated you need to replenish your water reserves.
The article mentions persistence hunting but says the efficiency of our sweat system is part of what made it work — something that makes us need more water.
Persistence hunting requires good thermoregulation. Sweating (loosing heat fast) makes persistence hunting possible and keeps body temperature down. Animals human hunt will get overheated. They have to stop to cool down.
ps. Endurance running helps with scavenging too, not just hunting.
> Animal metabolism produces about 110 grams of water per 100 grams of fat, 42 grams of water per 100 g of protein and 60 grams of water per 100 g of carbohydrate.
The amounts listed is a bit puzzling. For every gram of glycogen stored (stored carbohydrates) 2-3 grams of water is needed, so naively one would thing the number should be much higher for carbohydrate.
Just curious, really. I'm not aware of any serious downsides to ketogenic diets, except I suppose for the smell, but it doesn't take much glucose or starch at all before ketone bodies are no longer needed.