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This episode has been brought to you by our super generous supporters on Patreon here. We are
born to be Kings, we're the princes of the
universe oh oh hi. Sorry. I was just watching highlander for the 127th time today
And pondering my own mortality as one does but something occurred demand for the 103rd or fourth Viewing why?
After thousands of years of natural selection and evolution why don't we live forever or at least much longer in other words?
Why do we die?
Good stuff producers, Sam Grant and Matt weber take a good long look at their lives and try to figure out the secret to immortality
There is an organism on Earth that exists right now that may very well be the highlander of the biological world
The Hydra the Hydra is a small simple invertebrate that lives in freshwater and temperate and tropical regions and by all accounts so far
Don't appear to age not in the traditional sense anyway
This is because most of their bodies are comprised of stem cells most cells in our body have a specific function
Skin cells make up our skin nerve cells make up our brain and nervous system stem cells are undifferentiated cells
They have no specific task, but they do have the ability to turn into any type of cell necessary humans have stem cells, too
But they're only found within the first few days of embryonic development the hydra keeps these cells around for its entire life and it can
Use them to continuously regenerate itself
So if it can constantly replace damaged and dying cells can it live forever a study done by researchers?
Involved seen if there were any signs of aging when hydra were kept in an ideal environment
They kept over 2,000 hydra in an ideal environment for eight years
The death rate for the Hydra was the same each year at one in 167 Hydra. No matter
what age that particular hydra was over the eight year study none of the hydras showed any signs of senescence or
Deterioration of cellular makeup due to aging any damaged or worn out cells were replaced by an ample supply of stem cells making them
effectively immortal
In the wild hydra don't usually achieve immortality they die from disease predators
Or other unnatural causes the key to why humans die may be because of these same unnatural causes
But not in the way you would first think when we say someone died of natural causes
We usually mean they died of old age this isn't quite right however
We don't die simply because we get old we die because parts of our bodies start to malfunction or get infected with disease
cells in our body continually divide copying their genetic information with each generation
But sometimes a mistake is made in this results in mutation these mutations sometimes kill or damaged cells
But the really bad mutations let these damaged cells continue to propagate
This is cancer
The risk gets larger over time so because of natural selection cells only divide a certain amount of times before they die and are replaced
There's a gene in humans called P53 that is dedicated to solely stopping bad cells from multiplying
But it isn't foolproof
And it sometimes stops working the thing is the same type of gene is present in other mammals
Just in a less valuable form for instance there's a mammal called a naked mole rat that has been discovered to be almost entirely
Immune to cancer there is a similar situation in human body in terms of organ failure
Some of our organs can regenerate and some cannot some species however
Can the Mexican axoloTl is so good at regenerating its own organs it can not only replace missing limbs
but also parts of its brain and heart having the ability to prevent cancer and
Regenerate Organs seems like a huge survival boost you'd be able to live longer and theoretically reproduce more
Passing more of your immortality genes on to the next generation, so in the billion years the multicellular life existed on Earth
Why haven't all animals of all these abilities?
Why aren't we all immortal one idea?
Is that our genes have been selected to fail us at a certain point in order to conserve resources?
For the young and future generation this however is thought to be largely false for most of our time on this planet
Resources were effectively infinite we were nomads if we ran out of food in one place
We moved on to the next there hasn't been enough selective pressure to make this an evolutionary advantage
Not until recently how we run up against the limitations of the biosphere
And it just hasn't been enough time for this back to have affected the inherent lifespan of the population
So why then have we evolved to die to explain one part of the equation?
Let's take a look at the hydra again in general the only way that species dies is through
Unnatural causes like being eaten every day we have a chance of dying that has nothing to do with our organs or anything cellular
We could be mauled by a lion hit by a train
or simply Fallen head our heads walking down the street as their lives become longer the
Probability of dying in a way that has nothing to do with our genetic makeup
increases this has been especially
True throughout most of the evolution that has taken place in the human species before the advent of modern medicine and technology
humans
Just didn't live that long
usually not much beyond 40 years and it's only in the last century or so that our lifespans have suddenly increased in length and as
a consequence the chances of dying
Unnaturally our genes evolved thousands of years ago
and still operate under the assumption that we're probably going to die before we're 40 it is theorized that this 40-year plan evolved to let
Us live long enough to reproduce and raise our children and that a little longer so we can help out with the grandkids a bit
This helps ensure our genes survive on to the next generation and Beyond
But there comes a point where sticking around any longer
becomes unnecessary
And even detrimental to the survival of the species in terms of evolution your genes
See you in old age as a lost cause they're just too many random factors and freak
Accidents that could kill you for them to work too hard to keep you alive
It makes more sense for your genetic makeup to invest itself in you while you're younger and more apt to propagate the species a certain
Rapid number of cellular divisions are needed early on for growth and development
Which involves an intricate system of on and off switches this intricate Mechanism works better when you're younger?
Not so much for an older use basically your genes stop caring for you, when they assume in all likelihood that you're already dead
over long enough timescales people die
Species go extinct entire landscapes disappear if we were immortal and somehow beat the odds and didn't die from an accident
We would eventually be trapped in a world
Vastly altered from the one we evolved in hopelessly out of place and time unable to change and ultimately unable to survive
There's just no escaping death not in a statistical sense anyway
So what do you think do you want to live forever need to love?
forever you have any surefire ways to
Be immortal let us know in the comments and don't forget to like and subscribe and share this video if you wanted to achieve
Internet immortality special thanks to our patreon supporters for making this episode of the good stuff possible without patreon this show just wouldn't happen
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And you want these amazing ideas to propagate into the next generation and Beyond head over to our patreon page and support the show
Thanks for watching