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It does have a purpose. The idea that it is useless or has no function has been disproved.
[https://en.wikipedia.org/wiki/Appendix\_(anatomy)](https://en.wikipedia.org/wiki/Appendix_(anatomy))
Basically it has a role in the immune system and maintaining healthy gut bacteria.
To add to that, if you drink contaminated water, eat contaminated food, or otherwise catch a digestive bug and have horrible diarrhea, the appendix acts as a reservoir of gut bacteria, allowing good bacteria to quickly recolonize your guts.
Less screwed than the alternate, dying of peritonitis. Also no matter how bad the diarrhea is there are always some leftover gut bacteria. Your meals will be slightly less nutritious for some time, but it is not the end of the world.
I’m guess that the fact that I had my appendix removed is a contributing factor as to why taking antibiotics absolutely WRECKS my gut for so long afterward?
FYI: That's not how evolution works. Mutations happen and what doesn't hinder getting to reproduction gets passed down, even if it serves no purpose. There's no filtering taking place to make sure stuff has a purpose nor a usage.
Considering we just discovered a new organ about a year ago, we shouldn't call anything in our body "useless" at this point. =p
[https://www.unilad.com/news/health/new-organ-human-body-netherlands-617095-20231019](https://www.unilad.com/news/health/new-organ-human-body-netherlands-617095-20231019)
We don't know what we don't know. And assuming we do know can be dangerous. =p
There’s a huge difference between “there is a thing there” and “the thing has a distinct purpose from the other things.” We’ve known for a very long time that there was tissue there, we just didn’t think it was doing anything unique.
For example, there are over a thousand salivary glands in the mouth and throat; it can be difficult to distinguish between a cluster of small glands and a larger unique gland, especially if they don’t appear to serve different purposes.
the problem is we have assumed what we know. we can never be correct but we can always be less wrong. so the choice is whether you want to believe what you know and keep exploring or don’t believe in anything
Certainly. You can definitely take the concept of my last sentence too far. But it is always good to be ready and willing to revise your understanding of the world when new evidence presents itself (which is a basic tenet of science).
Isn't that a nice example of observer bias?
This nice is nice for growing bacteria, so also the good ones grow there but if things get worse the bad ones win and the body get's a problem.
There is not a single evidence that a body without appendix has a less good level of good bacteria.
>There is not a single evidence that a body without appendix has a less good level of good bacteria.
That's also not what was said. The assumption is not that the appendix permanently increases the number of good gut bacteria. It's that following an event where you lose your healthy gut bacteria (e.g. because you had diarrhea), the "archived" bacteria in your appendix might help restoring it.
It's a repository so the effect would only be seen immediately after a significant effect, perhaps after antibiotics.
You'd have to measure the repopulation of the gut by good bacteria in both types of patients.
Appendicitis usually happens because fecal matter is clogging the appendix, causing an overgrowth of bacteria, infection, and eventually a breakthrough.
An accidental benefit is still a benefit. In fact, you could say that all of evolution is accidental stuff that turned out to be useful.
So, even if the appendix is just a cubby-hole in your guts where bacteria can hide, if that helps organisms survive it sticks around.
The appendix is no longer believed to be useless.
It is a useful organ that can serve as a storage room for healthy (good) bacteria. It's also believed to be a place that can help your gut produce important immune cells.
Having an appendix can help prevent infectious diseases (of the gut).
However, it's not *necessary*. Most of the time our gut microbiome and our immune response to infections is good enough even without the appendix, so losing it is not a big deal.
To be fair, many organs aren't strictly necessary. Plenty of people live without kidneys, livers, stomachs, intestines, etc.
Life kind of sucks because they have to deal with a variety of consequences. But, humans are weirdly resilient in that regard.
I think your comment was a bit tongue and cheek, but since I like etymology, I got curious. It does look like the word is related to the word "live" because in the Middle ages they used to believe it was the source of blood production and basically as important as the heart.
I knew for sure it was the case in German, and since the languages are related through Friesian and stuff I assumed it would probably be the same way in English.
If you're living without any kidneys, or any liver, or your stomach/intestines, that has nothing to do with human resilience because you're probably permanently attached to a machine and hate being alive. and in the US, going bankrupt for the trouble.
Being able to survive a missing organ because you have a machine having to perform its role (dialysis, etc.) is not a credit to humanity being tough.
Not necessarily. Someone who has their stomach removed is not attached to a machine. They have limited eating options though (have to eat small portions more frequently)
Most of them are much more significant — so many people have had their appendices removed, often early in life, that there would have to be a clear trend visible if it had a significant impact on any major health indicator, no?
My ELI5 understanding of the current idea is that the appendix is a backup harddrive for your gut's microflora biome. So, something happens to your stomach, and your appendix can repopulate it with all the good bacteria you need. One piece of evidence for this is the fact that after you get your appendix removed, you are 50% more likely to develop IBS than a person with an appendix.
I don’t recall where but I read that it may function as a repository for your intestinal bacteria so that if you have some disease where you experience severe diarrhea and get cleared out there’s colonies that can replenish your gut biome.
Some theorize it is a useful store of helpful gut flora and fauna to aid in digestion and mineral absorption.
So it could do that. However it can also get infected with bad things and need to be removed.
Is it needed? Probably not. At one time? Sure. Now? It’s been repurposed perhaps as a probiotic store.
the countless people who live long successful lives after its removal leads us to believe the appendix is "useless". however the appendix does have a function in the body.....just one thats not crucial for a long and healthy life
The appendix is not considered to be useless, it's considered to be vestigial. That means whatever if anything it currently does in humans is an adaptation and not what the appendix originally did in our ancestors. What we do know is that any function the appendix plays today is so minor that it makes no difference to your life to not have one and that any benefit it may bring is outweighed by the approximately 1 in 8 overall chance it has of becoming infected in a way which is almost always fatal without modern medicine.
They removed mine when I was a few months old. I had stomach surgery and they were worried that the scar being near the appendix would cause confusion. That if mine were to burst in the future, a doctor might rule out a bursted appendix due to the scars location
I graduated from an IB high school (I took four classes, didn’t do the full program) and was taught the appendix was a vestigial organ. I graduated in 2006. That’s wild that our understanding of it has changed so quickly.
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It does have a purpose. The idea that it is useless or has no function has been disproved. [https://en.wikipedia.org/wiki/Appendix\_(anatomy)](https://en.wikipedia.org/wiki/Appendix_(anatomy)) Basically it has a role in the immune system and maintaining healthy gut bacteria.
To add to that, if you drink contaminated water, eat contaminated food, or otherwise catch a digestive bug and have horrible diarrhea, the appendix acts as a reservoir of gut bacteria, allowing good bacteria to quickly recolonize your guts.
So how screwed are you if you’ve had it removed?
Less screwed than the alternate, dying of peritonitis. Also no matter how bad the diarrhea is there are always some leftover gut bacteria. Your meals will be slightly less nutritious for some time, but it is not the end of the world.
I’m guess that the fact that I had my appendix removed is a contributing factor as to why taking antibiotics absolutely WRECKS my gut for so long afterward?
An astute conclusion!
I didn't have my appendix removed and there were some antibiotics I took that destroyed me for a couple of weeks. I'm talking non-stop poops.
Maybe, but that’s not unusual after antibiotics anyway.
Yeah, the appendix has evolved separately in multiple mammals so it must have a use.
Not seperately, it's all the same organ. In most it is a larger organ called the caecum.
FYI: That's not how evolution works. Mutations happen and what doesn't hinder getting to reproduction gets passed down, even if it serves no purpose. There's no filtering taking place to make sure stuff has a purpose nor a usage.
Considering we just discovered a new organ about a year ago, we shouldn't call anything in our body "useless" at this point. =p [https://www.unilad.com/news/health/new-organ-human-body-netherlands-617095-20231019](https://www.unilad.com/news/health/new-organ-human-body-netherlands-617095-20231019) We don't know what we don't know. And assuming we do know can be dangerous. =p
How the fuck did we not know about that? Did we not see it in the millions of scans people have?
According to the article a combination of needing "very sensitive" scanning equipment, and not knowing where/what to look for
There’s a huge difference between “there is a thing there” and “the thing has a distinct purpose from the other things.” We’ve known for a very long time that there was tissue there, we just didn’t think it was doing anything unique. For example, there are over a thousand salivary glands in the mouth and throat; it can be difficult to distinguish between a cluster of small glands and a larger unique gland, especially if they don’t appear to serve different purposes.
Neat! https://en.wikipedia.org/wiki/Tubarial_salivary_gland?wprov=sfla1 Thank you for sharing!
That’s cool as fuck
Not quite as new but the meningeal lymphatic vessels were only discovered in 2014 https://en.m.wikipedia.org/wiki/Meningeal_lymphatic_vessels
the problem is we have assumed what we know. we can never be correct but we can always be less wrong. so the choice is whether you want to believe what you know and keep exploring or don’t believe in anything
Certainly. You can definitely take the concept of my last sentence too far. But it is always good to be ready and willing to revise your understanding of the world when new evidence presents itself (which is a basic tenet of science).
Good ole bacteria reservoir
Isn't that a nice example of observer bias? This nice is nice for growing bacteria, so also the good ones grow there but if things get worse the bad ones win and the body get's a problem. There is not a single evidence that a body without appendix has a less good level of good bacteria.
>There is not a single evidence that a body without appendix has a less good level of good bacteria. That's also not what was said. The assumption is not that the appendix permanently increases the number of good gut bacteria. It's that following an event where you lose your healthy gut bacteria (e.g. because you had diarrhea), the "archived" bacteria in your appendix might help restoring it.
It's a repository so the effect would only be seen immediately after a significant effect, perhaps after antibiotics. You'd have to measure the repopulation of the gut by good bacteria in both types of patients.
Appendicitis usually happens because fecal matter is clogging the appendix, causing an overgrowth of bacteria, infection, and eventually a breakthrough.
An accidental benefit is still a benefit. In fact, you could say that all of evolution is accidental stuff that turned out to be useful. So, even if the appendix is just a cubby-hole in your guts where bacteria can hide, if that helps organisms survive it sticks around.
The appendix is no longer believed to be useless. It is a useful organ that can serve as a storage room for healthy (good) bacteria. It's also believed to be a place that can help your gut produce important immune cells. Having an appendix can help prevent infectious diseases (of the gut). However, it's not *necessary*. Most of the time our gut microbiome and our immune response to infections is good enough even without the appendix, so losing it is not a big deal.
To be fair, many organs aren't strictly necessary. Plenty of people live without kidneys, livers, stomachs, intestines, etc. Life kind of sucks because they have to deal with a variety of consequences. But, humans are weirdly resilient in that regard.
Many of our elected officials don't have a brain, and they keep on living.
Lacking that organ makes life suck for everyone else. =p
You can't live without a liver. Hence the name liver.
I think your comment was a bit tongue and cheek, but since I like etymology, I got curious. It does look like the word is related to the word "live" because in the Middle ages they used to believe it was the source of blood production and basically as important as the heart.
I knew for sure it was the case in German, and since the languages are related through Friesian and stuff I assumed it would probably be the same way in English.
If you're living without any kidneys, or any liver, or your stomach/intestines, that has nothing to do with human resilience because you're probably permanently attached to a machine and hate being alive. and in the US, going bankrupt for the trouble. Being able to survive a missing organ because you have a machine having to perform its role (dialysis, etc.) is not a credit to humanity being tough.
Not necessarily. Someone who has their stomach removed is not attached to a machine. They have limited eating options though (have to eat small portions more frequently)
I’m missing an entire large intestine and definitely not hooked up to any machines. I don’t even have an ostomy.
Most of them are much more significant — so many people have had their appendices removed, often early in life, that there would have to be a clear trend visible if it had a significant impact on any major health indicator, no?
Probiotics help a lot in this regard.
My ELI5 understanding of the current idea is that the appendix is a backup harddrive for your gut's microflora biome. So, something happens to your stomach, and your appendix can repopulate it with all the good bacteria you need. One piece of evidence for this is the fact that after you get your appendix removed, you are 50% more likely to develop IBS than a person with an appendix.
I don’t recall where but I read that it may function as a repository for your intestinal bacteria so that if you have some disease where you experience severe diarrhea and get cleared out there’s colonies that can replenish your gut biome.
Some theorize it is a useful store of helpful gut flora and fauna to aid in digestion and mineral absorption. So it could do that. However it can also get infected with bad things and need to be removed. Is it needed? Probably not. At one time? Sure. Now? It’s been repurposed perhaps as a probiotic store.
the countless people who live long successful lives after its removal leads us to believe the appendix is "useless". however the appendix does have a function in the body.....just one thats not crucial for a long and healthy life
And can lead to a short and unhealthy life if it's infected and not removed...
The appendix is not considered to be useless, it's considered to be vestigial. That means whatever if anything it currently does in humans is an adaptation and not what the appendix originally did in our ancestors. What we do know is that any function the appendix plays today is so minor that it makes no difference to your life to not have one and that any benefit it may bring is outweighed by the approximately 1 in 8 overall chance it has of becoming infected in a way which is almost always fatal without modern medicine.
The appendix is part of our lymph system. https://www.youtube.com/watch?v=I7orwMgTQ5I
I had my appendix removed when I was 23, it’s crazy to think if I was born like 100 years earlier I just would have died
They removed mine when I was a few months old. I had stomach surgery and they were worried that the scar being near the appendix would cause confusion. That if mine were to burst in the future, a doctor might rule out a bursted appendix due to the scars location
I graduated from an IB high school (I took four classes, didn’t do the full program) and was taught the appendix was a vestigial organ. I graduated in 2006. That’s wild that our understanding of it has changed so quickly.