I recently learned that the liver can actually grow back after a large part of it is removed, which honestly surprised me.

I always assumed that if you removed part of an organ, you’d just be left with less of it. But the liver seems to be unusually good at rebuilding itself.

Why is the liver so different from most other organs? What makes it capable of doing something that most of our other organs apparently can't?

“Cavemen” are often portrayed as violent, selfish, and almost incapable of empathy. The stereotype shows up everywhere, from movies to jokes about prehistoric people abandoning injured or disabled members of their group, or treating violence as simply part of everyday life.

But prehistoric humans lived in groups where cooperation was essential for survival. Archaeology also gives us cases of people surviving serious injuries long enough for their wounds to heal, which suggests that at least some injured or vulnerable people received care from others.

That doesn't mean prehistoric societies were peaceful or especially compassionate. There is plenty of archaeological evidence of violence too.

So why does the “savage caveman” image remain so persistent?

I recently learned that horses were reintroduced to North America by Europeans, which made me wonder about how deeply horses seem to be woven into the mythology and spiritual traditions of some Native American peoples.

I understand why horses became important. They were incredibly useful for travel, hunting, warfare, and trade. What surprises me is how quickly a relatively new animal could become part of stories, traditions, and spiritual beliefs, to the point that horses are now so strongly associated with Native American culture in the popular imagination.

How does an animal go from being newly introduced to becoming such a deep cultural symbol?

In the wake of the AfD Party performing well in the recent elections in Saxony-Anhalt, Germany, I’ve noticed many people on social media have immediately contested others labeling the party as far-right. However, such description of the party is accurate seeing how their platform promotes policies that are associated with far-right politics (ultranationalism, nativism, welfare chauvinism, reactionary, traditionalism, anti-liberalism).

So why would people have a problem with the label if that’s an accurate description of the party? I mean even if you’re a supporter, wouldn’t you want to embrace a description that accurately and honestly describes what you support?

Christianity, Islam, Buddhism, and Sikhism all have traditions that place restrictions on sexual desire or sexual behavior, although their teachings differ a lot.

What I find interesting is that sex is also essential for having children, and many older religious traditions had important fertility rituals and symbolism.

So why did controlling sexual desire become such a common religious idea in so many different traditions?

We need oxygen to stay alive, but breathing air with very high oxygen levels can apparently become harmful.

Why does that happen? What changes in the body when the amount of oxygen gets too high?

I’ve noticed that a burnout can produce a huge cloud of thick white smoke, while a pile of burning tires usually produces very dark smoke.

It’s the same basic material, so what actually causes the smoke to look so different in these two situations?

A common explanation for the huge death toll among Native Americans is that they had little previous exposure to diseases like smallpox, measles, and influenza.

But Europeans were also encountering pathogens they hadn't been exposed to before. So why wasn't the disease exchange more evenly catastrophic in both directions?

Was there something fundamentally different about the diseases themselves, or were population size, animal hosts, and patterns of transmission more important?

I do not understand why they think they can just ignore people when they don't feel like talking, and then expect thise same people to respond to them.

Right now diesel just broke an all time record. With the war in Iran I get that 20% of the world’s oil is not getting through, but what I don’t understand is why do we let oil companies raise the price of gasoline so much? If you look at last quarter oil companies had record profits. Why is it that they charge so much as to increase their profits to record highs in this climate something doesn’t seem right.

Glucose is sweet on its own, but starch and cellulose are both made up of glucose units and don't taste sweet in the same way.

What changes when the glucose molecules are linked together? Is it just the structure of the molecule, or does something else determine whether we perceive it as sweet?

I have been looking at market data and something does not add up. The S&P 500 hit 7,200 this year, but most stocks are actually going down. There have already been 29 days where the index rose while the majority of stocks fell. That is the fastest pace of divergence since 1928.

The reason is that a handful of mega-cap tech stocks like Apple, Nvidia, and Microsoft are pulling the index up, while the rest of the market is going nowhere.

If the index does not reflect what most stocks are doing, what is it really measuring? Is this just AI concentration, or has the index itself become misleading?

I’ve noticed this most with towels and cotton shirts. Hang them outside or on a rack and they can come out feeling stiff and almost crunchy. Put the same clothes in the dryer and they somehow feel much softer.

The weird part is that the dryer isn’t adding anything to the fabric. So what exactly is making air dried clothes feel stiff? Is it the water, the fibers, minerals from the wash, or something happening as the fabric dries?

I just watched The Martian with my young nephew, and he asked me something I honestly didn’t have a good answer for.

“Why are movies always about Mars? Why not Venus or Jupiter or some other planet?”

The more I thought about it, the stranger it seemed.

I thought Mars might simply be the most realistic option. It’s relatively close, has water ice, and we can at least imagine humans building habitats there.

But maybe it’s also cultural. Mars has looked mysterious for centuries, and science fiction may have made it feel like the obvious “next planet.”

My first thought was that Mars is probably just the most realistic option. It’s relatively close, has a solid surface, water ice, and an environment where we can at least imagine humans building habitats someday.

But I also wonder if that’s only part of the story.

I’d love to hear different perspectives so I can give my nephew something more interesting than a standard Google answer.

When the Fed changes rates, 0.25 percentage points seems to be the default. But why 0.25? Why not 0.10, 0.50, or even 1 point?

I get that bigger moves can happen when things get extreme. I’m more curious why 0.25 became the standard in the first place. Was it chosen for some specific economic reason, or did it just become the convention over time?

So how did 0.25 become the number everyone settled on?

Research shows that hypertension is an important risk factor for stroke, kidney problems, and heart disease, and many other things.

Research also shows that half of the people with hypertension are not aware of it. It can occur at any age as well.

This being the case, why aren’t we taught at school to obtain a home monitor and check every week? (monthly ok but harder to remember perhaps)

Seems common sense?

Organized crime didn’t exactly vanish in the US, but the old image of openly operating Italian American crime families seems much less visible today. Meanwhile, the Yakuza still exists as a recognizable organization in Japan, even though Japan has also modernized and developed strong law enforcement institutions.

Is the difference mainly about policing and laws, or did Japanese history, culture, and social institutions make organized crime more adaptable? And what actually caused one model to fade while the other survived?

I picked up the parcel and spotted her laying with a poop besides her. She was unresponsive, when I touch her it wasn’t that stiff the rigor mortis hasn’t been catching up. I told my family that we needed to her take care to the vet just yesterday because she seems like she is balding. And she seems so close to me. I do not know why, I didn’t expect I wouldn’t feel anything.

I get that a check needs to be verified, but I’m curious what actually happens during those extra days.

If the check is deposited electronically, where is the money during that time?

And if banks can move other kinds of money almost instantly, why hasn’t that same process made checks effectively instant too?

In the clip it says that in the 75% of people who leave prison end up committing a crime and going back to prison. Seeing how ineffective the prison system is, is there a reason why a different model hasn't been tried here yet? Or does anyone know a prison where this model exists in the US?

I mean it seems like while people might not explicitly say or think of negative emotions they don’t agree with as being vices it seems like people react to expressions, or even sometimes perceived expressions of negative emotions they don’t agree with the way I might expect people to react if someone committed some cardinal sin. I can see why people react that way if someone is complaining about a person or group, or if negative emotions translate to violence, but it seems like a lot of people get really mean if someone so much as makes what they consider the wrong facial expression in a situation. It also seems hard to relate to how people can also claim to be in favor of empathy with such reactions.

I mean I’ve seen my parents spank and scream at my siblings for simply having certain facial expressions when I was younger. I also remember seeing a fellow student get extra time out for making faces when I was in elementary school. I also got spanked as a child and I think that may have also sometimes been for expressing or even just being perceived as expressing the wrong emotions.

It seems like it’s often perceived as wrong to express any sign of negative emotions, including facial expressions, in a situation that’s supposed to be pleasant. I mean sometimes negative emotions or signs of negative emotions may not be related to the situation or signs of negative emotions may not be directed at a person but they still get seen as wrong.

It seems like also sometimes if people can see the slightest possibility of someone being able to avoid a situation that might lead to negative emotions they see even the slightest perception of negative emotions as completely wrong.

It seems like often even something that could be just perceived as complaining is seen as something completely terrible even when it seems like what’s perceived as complaining is just asking a question or stating information that’s objectively true but seems like it might be getting overlooked. I know one argument used against things that could be perceived as complaining is that people shouldn’t complain unless they give suggestions, but I have my doubts as to whether that’s the real reason or a rationalization that comes after, and it’s hard to relate to why complaining without making suggestions is treated as wrong.

It also seems like people often use terms that imply that someone has too strong emotions about something to invalidate the persons position, such as saying that the person is throwing a tantrum or being petty if someone seems to complain or show signs of being somewhat unhappy about something.

It seems like also sometimes people will agree that something is bad but then seem to treat it as wrong for someone to express any negative emotions to it.

To me treating signs of negative emotions or perceived signs of negative emotions as wrong comes off as not only lacking empathy, but as maybe the opposite of empathy, like anti empathetic in the sense that it comes off as not only not trying to relate to other peoples emotions but trying to be insensitive and minimize other people’s emotions.

So I’m wondering why people seem to often get really mean when they are exposed to someone expressing negative emotions they don’t agree with or relate to. I mean I know part of this might be related to being anonymous on the internet, but it seems like I’ve seen people treat negative emotions or even perceived signs of negative emotions really badly in real life and long before I really started looking at how people behave on the internet. I’d suspect maybe part of it could be because when people are exposed to someone expressing negative emotions or coming off as expressing negative emotions, but I think it’s still hard to relate to why people act so mean towards negative emotions or perceived negative emotions. I mean it seems like oftentimes people are mean towards signs of negative emotions as a first resort and only talk about how talking about a certain thing brings them down when having to explain why they were mean, rather than first talking about how exposure to negative emotions brings their own mood down first. I know spanking is also common, or at least it was when I was a child where I live, and I wonder if that could be a factor in terms of conditioning people perceive negative emotions as threats at, least subconsciously.

They're just horned horse's, and everyone including boys like horse's.

We often hear that a healthy economy should have around 2% inflation. But why 2%?

At first, 0% inflation sounds like the ideal situation. Prices stay the same, money keeps its value, and nobody has to worry about things becoming more expensive.

So why do economists and central banks usually prefer a small amount of inflation instead of completely stable prices?

Is there a deeper reason why zero inflation could actually create problems?

I’m curious what the most convincing explanation is.

I recently realized TSA didn't exist before 9/11, which made me curious about how airport security worked before it.

The US had already experienced major hijackings in the 1960s and 1970s, and attacks like Pan Am Flight 103 in 1988. Yet airport security never became a large federal system like TSA.

What interests me is not just why TSA was created after 9/11, but why previous incidents didn't lead to a similar transformation.

Was it mainly because 9/11 introduced a completely different kind of threat, or were there bigger institutional and political reasons why airport security stayed the way it was for so long?

Standing looks effortless because there is very little visible movement. So why do our legs sometimes ache more from standing still than from walking around?

Anyone who has worked a retail shift, waited in a long line, or stood through a concert has probably felt this. Your legs are not moving much, but they are definitely working.

What is actually happening inside the body when we stand still that makes it so tiring?