Kind: captions
Language: en
we have two tubes that are right next to
each other in the throat one is for food
drink saliva mucus snot whatever you're
gonna swallow
all of that stuff must go down the
esophagus the food tube and end up in
the stomach and right next to the
esophagus millimeters away
is the windpipe or the trachea which
goes down to the lungs throat heart
feces genitals every organ from moment
to moment keeps us alive and ensures our
survival the genitals are in a way the
opposite how would you improve
the penis and the vagina
the following is a conversation with
jonathan weissman a physician and writer
of the unseen body a doctor's journey
through the hidden wonders of human
anatomy he has practiced medicine in
some of the world's most remote places
including the alaskan and russian arctic
antarctica
and the himalayan mountains of nepal
this is alex friedman podcast to support
it please check out our sponsors in the
description and now to your friends
here's jonathan reisman
you wrote a book called unseen body
all about the human body the messy the
weird the beautiful and the fascinating
details
so from an evolutionary perspective are
most parts of the human body a feature
or a bug
is it
like the optimal solution or just a duct
tape solution great question i think
that
most of the time the way the body works
is the best solution
i haven't seen many alternatives so it's
hard to compare
but
i think you know there's some parts of
the body that make more sense than
others you know the way our hands work
for instance
um you know the muscles are up in the
forearm and then the tendons kind of
come down like strings on a puppet and
just the dexterity it gives our hands is
just really
amazing and it's hard to imagine a
better
a better tool than the human hand to do
everything from you know hold things to
play piano and do a million other daily
activities that we do
one thing i talk about in the book
there's some other body parts that seem
to be lacking that kind of brilliant
design such as the throat you know where
the
food drink are swallowed and air is
inhaled and they kind of those two paths
come within millimeters of each other
and you slip up once you laugh while
eating
or you speak while trying to swallow and
you die from choking so it seems less
than optimal though i'm not sure it
could be better from the way we're kind
of formed in the womb as a beginning as
this tiny little tube i don't think it
could have been done any better or
there's any other way to do it but it is
an unfortunate thing that
you know does lead to some problems so
the hand if i could just linger on that
for a second
you talk about the wisdom of a design
in the book
what are the important things about the
hand it seems like very
useful for many things and it seems to
be quite effective
a lot of people think the thumb
is foundational to um
to the human civilization
um is there any truth to that
i think that is true actually one of the
ways in which the importance of
individual fingers comes
to attention is when people have severe
injuries to their fingers for instance
um i have a story in the book about a
guy whose thumb is nearly ripped off by
his dog's leash
and you know when we when plastic
surgeons who are often the ones to
repair that sometimes it's orthopedic
surgeons they will debate you know how
important is it to save this finger or
how important is it to save you know
let's say the kind of
tip uh the one-third the tip one-third
of one of your fingers you know it
depends on the length that you'll lose
it depends on which finger and so the
thumb really is the most crucial um just
you know for your occupation in most
cases to
just daily life um and your ability to
get around take care of yourself and
others so
you know they'll be more they're willing
to go further do more surgeries more
aggressive therapy to save a thumb let's
say
than you know the tip of your pinky
finger so in that way i do think the
thumb you know does seem like the most
important in many ways it's nice that
there's backups i wonder if that's part
of the feature or is it just the
symmetry that nature produces you think
you think that two hands is like is it
about the symmetry or is it about backup
we'd be much less formidable hunters
gatherers
survivors in any way
if we only had one hand so i think
that is important to have two so we can
you know even everything from kind of
spearing an animal to firing a bow and
arrow to butchering an animal you really
need two hands to do it very effectively
but can you do a better job with three
great question
and we'll never know perhaps
um
you tweeted now i'm gonna analyze your
tweets like it's shakespeare sometimes
you tweeted that quote millions of years
of sex and death
designed the human body
it's like poetry
are those two basic activities
uh
basically summarize everything that
that resulted in humans on earth so like
uh is it is that a good summary
of the evolutionary process that led to
this conscious intelligent being is
death and sex
in a way yeah and so sex is how more of
us get made obviously and death is how
we get weeded out or the gene pool gets
weeded out and certain genes survive and
others don't and you know the age at
which we die
whether it's before we've you know had
sex and reproduced ourselves is a big
factor and who survives who doesn't who
passes on their genes and what the
future
of the body looks like you know who
lived and who died
before they were able to be at
reproductive age a million years ago was
pretty important in what we look like
now
um and perhaps
how we have sex and die now will
determine what we're shaped like
unless technology has an even bigger
role in that you know a million years
from now do you think that's fundamental
to like if there's alien civilizations
out there that have uh the same order of
magnitude of intelligence or greater do
you think that we will see something
like sex and something like death so the
reproducing
and this selection process plus the
weeding out
of the old to make room for the new is
that kind of
foundational to life i would think so i
mean it sure seems to be on earth you
know perhaps in some distant future when
medicine is nearing you know perfection
and people can live a really long time
uh maybe we won't even need to reproduce
as much
or something like that you know it's
hard to even know what
what life will be like in the distant
future but i would guess that any alien
civilization will have the same
dependence on who who has sex and who
dies well that's the problem with
immortality how are we going to clear
out
the old
to make room for the new which is as
kind of um
it's like a framework of adaptability to
changing environments so as long as the
environment is changing and it seems to
always be
because this the entirety of the earth
system is a complex system it seems like
you have to adapt and to adapt you have
to kill off the stubborn old
ideas
and uh unless there's a way to like not
become stubborn and old but it feels
like
the nature of wisdom
is stubborn and old like that's that's
what wisdom is it's like the lessons of
life solid the lessons of experience
solidified
and the solidification is the thing that
actually prevents you
from reinventing yourself
to adapt to the new
um
changing conditions but then again why
not have that both of those modes like i
have two minds and one person one
immortal person that like
in the morning they act like a teenager
in the evening they act like a old wise
man
that's possible so you can imagine
within one mind
both modes
but those are required you have to have
you have to have the ability to
completely reinvent yourself which is
what death does
in an ugly way
or a beautiful way depending on your
perspective depending whether you take
the human perspective of the human uh
the nature's perspective and then you
have to have the selection so
competition so sexual selection
it's an interesting interesting little
planet we got what's the weirdest part
function concept idea
about the human body to you we'll talk
about fascinating details but what's you
i should say for people that should uh
read your book they will come face to
face with the fact that you do not shy
away
from the weird and the wonderful of the
human body it's like
it's fun but it's honest
uh so given that
sorry to make you pick one of your
children but uh what's the weirdest one
would you say
the weirdest body part um or concept
or function
so the chapters you divide it up kind of
into parts
but
there could be a thread that connects
all of them the weirdness
maybe
or maybe the the texture of the
substance could be the liquids the
solids i don't know
definitely every body part and bodily
fluid has their own um kind of both
gross and fascinating aspects that's
probably why i'm a generalist as a
doctor and couldn't just as you said
pick one of my children become a
specialist because i like them all
um
i feel like one of the strangest
concepts about the human body is that
kind of the aspects of it that are the
most universal that we all do are the
most taboo socially um i wouldn't have
expected that if i had you know just
looked from the outside like what we do
in the bathroom what we do in the
bedroom
what we do to our
own genitals what we do to our uh you
know
quote-unquote private parts they're
private even though it's sort of the
thing that we have all have in common
um is the most we try to hide from other
people and don't talk about polite
company i mean it makes sense as a human
living in the society but from the
outside it sort of might be surprising
how do you make sense of that if you put
on your
sigmund freud hat
the thing we all do why do we make that
a taboo thing is it because we like
taboos maybe we get off or maybe our our
our our kinks as humans is to have
taboos and it's kind of efficient to
have taboos about the things that
everybody does
like you can make walking taboo or
something i don't know but just uh maybe
that's what we love that's what's
exciting to us is the is the forbidden
i think yes society loves rules for sure
they loves
some societies more than others you know
they love controlling how you think and
what you do in public versus private you
know there's a lot of societies where
for instance parents have sex in front
of children
um not you know for instance like in in
a traditional inupiat eskimo societies
that was sort of normal
i mean but what are you gonna do go
outside in the middle of the winter in
the arctic and do it out there of course
not so um you know there's different uh
different taboos in different societies
some taboos make perfect sense some
taboos are
even public health measures you know
like as i talk in the book about in in
india where they
uh you know the hands are symmetric as
you said but in indian culture and the
left hand is taboo and the right hand is
what you use for shaking hands
for eating for other things and the left
hand is
the dirty hand that you use for wiping
your own bottom you know that's the
toilet paper as your left hand so
um while the body is anatomically
symmetric the taboo creates this pretty
intense asymmetry uh but for a good
reason you know you probably shouldn't
be shaking hands with other people with
the same hand that you use to kind of
clean your bottom so in that sense it
makes sense
yeah maybe the roots of it make sense
but the way it propagates especially as
the times change might not because you
can wash your hands
but the the taboo remains right society
is very slow to change
what is the most fascinating part
function or concept in the human body
so
you know something that fills you with
awe
i guess the most obvious one is the
brain partly because it's so you know
sort of poorly understood that we
understood
understand more than we ever have in the
past there's still so much that we don't
understand about
how the lump of matter and our skulls
kind of creates this subjective
experience that we all kind of
understand quite viscerally
that's an easy one i would say the
kidneys are an underappreciated organ uh
they
the the way they tinker with the
bloodstream
raise levels of this lower levels of
that kind of our entire lives from
uh inside the womb until we die is just
really incredible and when you look at
how much energy different organs consume
the brain and the kidneys are two of the
biggest ones because the brain obviously
in us is always active and controlling
parts of the body but the kidneys are
just
consuming a ton of energy to do what
they do they're kind of the unsung hero
of the body relegated to the back of the
abdomen like some forgotten organ but
they're they are great i did consider
being a nephrologist which is a kidney
specialist because i was so taken with
the kidneys but you know decided i like
all the organs so couldn't pick just one
so your book is ordered in a particular
way it's
throat heart feces genitals liver
pineal gland
brain skin
urine fat
lungs eyes
mucus
fingers and toes and blood
alright
first of all great great uh chapter
titles
uh is there a reason for this ordering
or is it all madness
there's a few different reasons that
went into it um i did want to start with
the throat for
the reason that
it kind of presents uh the topic of
death which is sort of obviously very
important in the training of a physician
in the career physician it's a big part
of what i deal with you know on the
first day of medical school
we started the dissection of a cadaver
in the class called anatomy lab and so
in a way we were kind of thrown right in
there in the beginning like this is the
end of the human story you know
understand this and then we sort of
backed up to the beginning with
embryology and reproduction and stuff so
it's kind of like we got and i got
thrown into that
right right away right in the beginning
kind of like here's a dead body now
start cutting it apart and learn the
name and function of absolutely every
bit of flesh how did that change you
that first
experience with the cold honesty of
human biology all right that's exactly
what it was it's cold honesty about the
kind of the story of of each individual
human body it has an end and that's it
um i think that well
actually before the end of that first
day so what we did on that first day was
study the superficial muscles of the
back like the lats or latissimus dorsi
and some other muscles you know we cut
through the skin of the back my cadaver
was laying face down on this metal
gurney we pulled back the kind of
plastic sheets that would keep him moist
for the next four months as we dissected
him
cut through the skin on his back and
then started dissecting through the
superficial muscles of the back and that
was really all we saw that first day
we didn't get any deeper didn't enter
the abdominal or
chest cavity to see internal organs but
i was so fascinated with this sort of
behind the scenes look at how things
work in the body how you move your arms
how you arch your back you know these
are the muscles that do it
that i decided i wanted to donate my own
body for the same purpose um so i made
that decision literally before the end
of that first day of class and i i'm
still sticking to it
so someday there will be a medical
student
that can
watch and listen to this podcast and
while dissecting your body it could
happen they might not know that that
person they're listening to on the
podcast will be the carcass in front of
them but uh like we don't we never learn
the universe will know the universe and
they will acknowledge
the irony or the humor the absurdity of
that the universe will chuckle but the
medical student won't know
because they never as i did not learn
any uh you know personal information
about the person
only what i could glean from looking
inside him which actually tells you
quite a bit i knew he was a smoker i
knew he had coronary artery disease you
know you get a a window into i knew he
was overweight you get a window into
people's lives just by looking in there
in their bodies after death other other
um
cadavers in the lab not my own
or i shared one with three other
students but other cadavers some had you
know metal joints like a knee
replacement some had a kidney missing so
they probably and we could tell it was
surgically removed not that he was born
with one
uh and we could tell that he probably
had a kidney tumor or cancer that was
removed so you you do get an insight
into people's lives from
you know picking them apart after
they're dead uh but you don't know their
name or what podcast they've been on
so the as the book title says unseen
body
so it it tells
some kind of story of your life
so it does capture the decisions you've
made in your life the things you've done
that might be kind of secret
to that person and maybe to a few others
that knew
him or her well
it's so fascinating so
what kind of things can reveal like what
kind of choices in terms of the injuries
the
the the catastrophic events
the
lifestyle choices of smoking and diet
and all those kinds of things what what
what
what can you see what kind of history
can you see about the human before you
so all those things you mentioned are
things you can see you can you know take
the skin for example right most things
that happen to us
leave a mark uh you know as i say a kind
of a story written in the language of
scar where it tells you injuries you've
had and same thing with animals you know
i've
i've seen deer hides that have marks
that look like they're made by maybe a
barbed wire fence something like that
you can tell
you know you sometimes it's conjecture
but you can sort of imagine what might
have happened to cause that perhaps you
know two bucks were fighting and one got
injured with an antler um and the same
with humans you know i have scars on my
body and when i
notice them i remember what happened you
know i
got a big cut of my hand when i was 13
and it's still there and i
remember what happened uh you know every
time i look at it and so in that way
only i might know that story but other
people you know when they dissect me and
notice the same scars they can kind of
can fire their imagination as my cadaver
you know did for me they know that there
is a story there that's such an
interesting way that the skin does tell
a story
uh both tattoos and scars
some of the damage you've done right and
even when i when i evaluate a patient i
can use scars
to help me make medical decisions so for
instance someone that comes in with
abdominal pain into the emergency room
you can see scars on their abdomen that
tell you about you know the past kind of
activities of a surgeon perhaps i know i
recognize the scars that are left when
someone has their gallbladder removed
the scars when someone has their
appendix removed when maybe when
someone's had a hysterectomy and that
can tell you
what it might be or what it isn't you
know if someone doesn't have an appendix
their abdominal pain is not appendicitis
end of story so in that way
i'm sort of looking at these the the
tracks or the footprints of past
surgeries to tell me what what might and
might not be the cause of this patient's
abdominal pain which is kind of my main
job in the er is figuring out what's
causing it and to help them
is there
ways to get more data about the human
body as we look into the future of
medicine biology that would be helpful
to fill in some of the gaps of the story
so
you know you have
you have companies you have research
that looks at you know uh collection of
blood over long periods of time to see
sort of
you know paint the picture of what's
happening in your body mostly to help
with lifestyle decisions but
but also just you know to anticipate
things that can go wrong and all that
kind of stuff is there can you just
speak to
um
a greater digital world that we're
stepping in how that can help
tell a richer story
i certainly think that we
have more data than we know what to do
with right now especially with kind of
direct-to-consumer medical devices you
know smart watches etc that are just
collecting these reams of data i have
not seen them put to i think the
eventual use that they will
um i think that the
potential is is sort of just um you know
unimaginable and i hope we're heading
into a new age where you know you can
determine for instance is a person going
to have more of the dangerous side
effects to a drug based on their
genetics or are they going to tolerate
one drug better than the other you know
based on on their genetics and
we are slowly moving into that age and
especially the age of kind of completely
synthesizing drugs in a lab
um you know much like
for instance some of the covid vaccines
actually like moderna never had a vir
the virus in their lab they made that
vaccine completely without ever having
the virus themselves just by having the
genome which is sort of astounding and
there's a lot of potential going forward
you know based on that technology and
some others well i didn't know that so
they basically it's all in the computer
it's computational right you have the
genetic code you have tremendous power
even if you don't have the organism
itself
what do you make of elizabeth
holmes and efforts like that first of
all
i am
a
curious
i'm drawn
to the darkness in human nature because
that somehow reveals
um
the full spectrum of what humans could
be
so there's a lot of controversial
thoughts about who she is and her
efforts and so on
i think you may have even tweeted about
it but i've read a lot of your tweets so
i'm not forgetting um but what do you
make of her and those that both those
efforts and the charlatans
that sort of
snake oil salesmen
that's
promised those efforts
to do more than they currently can
i think that her you know that goal that
she had that she created theranos to try
to achieve
to use less blood in tests is a very
worthy goal and a huge frontier that we
have not
achieved and that i hope we will achieve
so i understand why you know what
someone describes what a huge step
forward that would be and it would be
indeed i understand why people put a ton
of money behind it can you describe what
was the promise what what are we even
talking about what's their nose what
just uh for people who don't know so
theranose is a company that was
basically started to revolutionize the
way medical blood tests are done
both to use a whole lot less blood in
doing it you know if anyone's ever been
to the doctor and had five to ten tubes
of blood removed from them it can be uh
quite surprising how much they take out
uh and and it's
you know that's the limitation of our
technology that we need those volumes of
blood to run all the tests that we want
to and so the promise of theranos was
that perhaps with a single drop of blood
we would be able to know as much about
the person's the condition of their
their body um without drawing all that
blood and and thereby you know there
would be these devices she was going to
create that would sort of do it you put
a drop of blood in it spits out
everything you ever wanted to know about
what's in your bloodstream and in a way
that would make it so much easier you
know it could be you could have one in
your home theoretically and you i don't
know why you'd wonder what your
potassium level is on any given day but
you could check if you wanted to um and
so that that goal is very worthy you
know i i put that goal up there with
uh the the frontier of making
painkillers that are as good as opioids
without the addictive quality you know
that would be such a huge revolution if
we did have that in medicine but
and particularly for me because i
trained in both pediatrics and internal
medicine so i learned to care for both
children and adults in children we do
draw much less blood they have a much
lower blood volume and we use these tiny
little tubes to draw their blood
and we seemingly get
equivalent information out of the larger
tubes we draw from adults and i'm still
unclear to be honest why we can't draw
that little amount of blood from adults
it seems technically possible i don't
know what the barriers are i'm sure
there are or else we'd be doing it
but i do think that that is a very
important goal and if theranos had done
it they would have really revolutionized
the practice of medicine
so to
return to that
cadaver that first day
uh when you got to meet with the with
the dead with a
human body that's no longer living so
how
how quickly
did it take for you to get used to sort
of uh he said looking at the surface
muscles of the back
i mean
that can be overwhelming as a thought
and people listening to this that have
never dissected anything might might be
overwhelmed by that thought so like how
quickly were you able to get used to
the brutal honesty of the biology before
you
for me it did not take long at all i
guess i've not never been a squeamish
person so for me it was kind of riveting
and fascinating right from the first
moment but i do know some of my fellow
classmates did have some trouble with it
some of them i
heard had nightmares in the first few
weeks of anatomy lab
and but then everyone as far as i know
got used to it and that was also
actually a big lesson for me that it's
pretty amazing what people can get used
to in their daily lives and i kind of
extrapolated that to people living
through war and through you know just
terrible uh situations and
living under um you know oppressive
regimes and it it really is amazing what
people can get used to almost anything
but you know in war
people
often come back and they have nightmares
they suffer through it there's ptsd
there's uh there's a lot of complicated
feelings with that
are echoes of those same complicated
feelings possible
in the case of training to be and
becoming a doctor
that's a good point yeah i think you
know sometimes just as you know a barbed
wire fence can leave a scar on your skin
you know emotional uh psychological
experiences can leave a mark on your
brain or your memory and i think that
that definitely could be um
could be a problem in medical training
you do see a lot of things that are
very shocking very repulsive things that
you'd never forget i know one of those
students that had nightmares initially
went on to be a surgeon so i imagine
she's not having the ptsd of kind of
seeing inside her first dead body
because she sees inside them all day
every day now
but i'm sure it it could you know we we
go on to see so many um kind of
grosser or more shocking
things in medical training through
medical school and then by working with
actual living patients not just dead and
embalmed bodies
so i do think that things can leave a
mark but i don't think that initial
cadaver would be the most traumatic
yeah but maybe some of that trauma the
demons make you a better surgeon just
like
some of your own psychological trauma
might make you a better psychiatrist
returning to the ordering
is that order is a chaos to the ordering
of the chapters from throat and heart
and feces and genitals all the way to
fingers and toes and blood
so i i did mention that you know throat
was the first one because i kind of
wanted to throw the reader right into
the the brutal honesty of death
and i followed it up with feces as the
third chapter and in a way partly to
also throw them right into the deep end
of
how i like discussing parts of the body
and revealing their gross and
fascinating aspects so i didn't want to
hide anything you know when you train to
be a doctor everything is on the table
literally in the cadaver lab but also
just
you know you deal with blood and piss
and vomit and feces and that's kind of
the medium of your craft and
yes medium or the craft that's right
right like if you're a painter
this is the paint
exactly and then you have to create a
masterpiece with it
uh like almost like a dance because
there's multiple painters one of the
painters is the biology so let's return
to throat you mentioned it's a weird one
so first of all
a friend of mine said i i just see
humans
as a
like a bunch of holes that just walk a
walk around
it's
not
untrue it's a funny way to look at
humans so we have ears we have nose
uh we have mouth
we have
um the sexual holes vagina penis
and then uh
you know what's the uh medical term for
your
yes anus thank you
uh this is this is a very technical
discussion the rectum's further in don't
confuse the two oh that's very important
what what
is there a difference between throat and
mouth by the way so when you say throat
are we talking about
when that hole actually became becomes
tubular
so the throat i would count as just sort
of the very back of the of the you know
the back of the mouth where the nose
also comes down and meets it where the
tonsils are and the uvula
but you're right that you know we are a
bunch of holes but more accurately we're
a tube right we start in the womb as
kind of this microscopic little disc
almost like
a uh
you know a flat bread and then we're we
roll in almost like a burrito into this
tube and we're a simple microscopic tube
and from there we grow into this bigger
and bigger tube and we become more
complicated and each end of the tube
does split into various holes so all the
holes you mentioned at the front end of
the tube the front end of her body right
it splits into the nose
the mouth the ears the sinuses the the
tube to the
lungs which is the windpipe the tube
down to the stomach which is the
esophagus
and then the other end of the tube
splits as well uh you know men end up
with two holes
and women end up with three holes
um you know the urethra the vagina and
the anus and men just you know the
urethra and kind of the reproductive
system they share a hole so i'm learning
a lot today
it really is incredible that you start
from sperm and egg and you have some dna
information and from that the building
project begins
and then what that leads to is like a
like a like pizza dough and then you
roll it
into a tube and that tube then
eventually
sort of becomes more and more
complicated and gets
eyes and a brain
and then uh can create a twitter account
so for so from
it's it's really incredible that we're
just a fancy tube
right we are and we sprout eyes and a
brain and a sense of smell and taste
pretty much to regulate what comes in
the front of the tube you know we don't
want to eat anything dangerous or
poisonous you know we want to choose
what we eat
even choose who we kiss well we seem to
be motivated by what comes out of the
tube as well
in part
that's not just output it's a feedback
mechanism seemingly like we're also
monitoring the functioning of the output
we're not just obsessed about the input
we're very obsessed with the output
you're absolutely right about that
people you know have medical complaints
about their output very often that are
you know i'm never i never cease to be
surprised by a new kind of complaint or
observation about the output i think
people have gone to wars over
the output and uh maybe sometimes the
lack of the output or the desire for
output for the particular other humans
that you fancy the brain and the eyes
that sprouted somehow convinced
the
the rest of the body that this one
particular other tube is fanciful so
you're going to go to major wars and
lead global suffering because because of
the fancy and the desire for additional
output with the other
uh tube okay
so that's
so
uh on the throat
that part of the tube
is it uh
you said the design is not
you could have thought of maybe a little
bit better options because it's too
multi-functional is that
can you sort of elaborate on the
multifunctional nature of this part are
a lot of parts of the human body
multifunctional or do you find that more
specialization
is going to get the job done better
there is a lot of organs for instance do
have multiple functions you know the
pancreas has two it's like two organs in
one one you know secretes hormones like
insulin into the bloodstream and the
other aspect of it secretes uh digestive
enzymes into the gut to help you digest
and absorb food the liver is like 15
organs in one it's just amazing how many
different things it does
but the throat you know so basically the
problem with the throat is as i said
we have two tubes that are right next to
each other in the throat one is for food
drink saliva mucus snot whatever you're
gonna swallow
all of that stuff must go down the
esophagus the food tube and end up in
the stomach and right next to the
esophagus millimeters away
is the windpipe or the trachea which
goes down to the lungs
and your your throat does these daily
gymnastics to
keep everything but air
out of the windpipe because you know you
slip up once and you can die
uh you can choke you know you laugh or
speak while eating and its curtains
unfortunately so it seems like you know
every aspect of the body when i was
learning about it in med school seems so
brilliant and so perfectly designed by
evolution or whoever you might think
designed it um to you know favor
survival to enhance life
uh but the throat seemed the opposite it
seemed set up almost for failure
and uh you know we developed all these
mechanisms as a compensation right we
have the gag reflex whenever food or
something is headed towards your air
pipe your windpipe or down to your lungs
your throat has this sort of like
rejection of it it pushes it away in a
gag reflex
at the same time we have a cough which
is something our body does when
something inappropriate does get down
the windpipe you know when we get a
little food down the wrong pipe uh we
end up coughing and the coughing does
usually flush it out and get rid of it
we even have something called the mucus
elevator in our lungs which is this
constant flow of mucus up the airways up
to the trachea dragging with it all
kinds of particulates that we've inhaled
and perhaps some food that went down the
wrong pipe and drags it up into the
throat and we swallow it kind of
unconsciously all day every day is the
truth even the mechanism of swallowing
is super complicated you know uses a
number of cranial nerves it uses over 15
different muscles
um it's this coordinated act to keep
food out of the airway you know it you
can see someone's adam's apple and their
neck kind of jump upward when they
swallow
which helps lift the airway up against
this kind of the the epiglottis which
plugs it closed and allows food or
swallowed drink to kind of skirt just
past it but every time we swallow those
things do come within millimeters of
going down the wrong pipe and it's just
thanks to these kind of compensations
these adaptations we have to the danger
of the throat that keeps us alive
as i actually took a sip of uh water
it's it's kind of
it makes you appreciate
the wonderful machinery of it all
uh by the way we have uh pulled up your
instagram that people should follow you
have a post about the throat
and then just showing so many different
components from the tongue
to the trachea the esophagus
just the entire machinery of it all
the teeth for the chewing
it's so interesting and so a lot of the
structure of this the anatomy
and the physiology does it echo other
mammals
are we so are we just basically
borrowing a lot of stuff from evolution
and maybe
making small adjustments maybe due to
the fact that we're not using our mouth
to murder
things
as other predators might we use our
thumbs exactly we have hands we don't
need to bite them
um yeah there's a lot of overlap between
different animals which i find uh very
comforting and fascinating you know
someone asked me is there any animal in
which the throat is better designed and
i my first thought was whales because
the blowhole is kind of up on the top of
their head so i was thinking oh maybe
maybe they are set more separate but
when i looked into it actually no you
know the paths do come very close just
like in us and
i saw a paper about some new discovered
organ that actually helps keep food and
drink out of the airway in wales that
they hadn't ever noticed before so it's
a different mechanism but the same kind
of basic problem is that you know where
tubes and the air tube and food tube are
right next to each other how well do we
understand so just even lingerie on this
little part is there still some
mysteries about the complexity of the
system because you mentioned
just even for swallowing all these parts
in the brain that are responsible and
all all the different things that have
to like an orchestra play together do we
have a good sense from both a medical
perspective and a biology perspective or
is there still mysteries there's
definitely still mysteries we understand
a lot about for instance how the
swallowing mechanism you know is
coordinated it's
in the brain stem sometimes using some
higher levels of the brain
but it is a very thoughtless thing as
you mentioned when you drink the water
you know it's not something we have to
think about thankfully or we'd be
thinking about it all day
there's a lot we don't understand about
the basic mechanisms perhaps about how
the nerves fire and how they kind of you
know
coordinate on them on the microscopic
level how ions rush into and out of
nerve cells to kind of create that
electrical signal but
we sure understand a heck of a lot and
it's very fascinating
so moving on to
chapter two and we'll jump around uh he
actually said the liver um
does a lot of things i also saw you
retweet something
where
it said uh you know showing that the
liver is bigger than the heart
which is the body or the universe's way
of saying you should drink more and care
less it's a good line uh so you you give
props
uh like you said to the kidney to the
liver to the maybe
to the organs to the parts that don't
often
get as much credit as they deserve but
let us go for time to the human heart
we get chest pain
we talk about it when we talk about love
for some reason why do we talk about the
heart when we talk about love there
sometimes can actually be some chest
pain involved in love i remember when i
was a med student i was very smitten
with another medical student it was
totally brilliant and beautiful
and it actually does cause this kind of
burning in your chest i don't know what
that is i don't think it's from the
heart itself
i don't know if it was like acid reflux
because i was so nervous i'm not really
sure
but i definitely felt something in my
chest whenever i saw her i don't know
what that is but you could see why
someone might think oh you know maybe it
is your heart that's kind of the most
prominent organ in your chest when
people come to the er with chest pain
you know the big question is is it my
heart and that's my main job is figuring
out if it is or not
so i could see why um
you know the way ancients saw the
functions of different organs is
fascinating but often
hard to explain
would it be fair to say
that if you look at the entirety of
human history
the way most people die has to do with
the heart
well like in america today um
cardiovascular disease and and cardi you
know coronary artery disease is one of
the most common perhaps the most common
cause of death you know a 100 years ago
200 years ago it was probably not people
were not living as long and people were
dying of infections that we tend to die
less of these days
sure um that's true but in terms of
things to stab
so i'm trying to sort of introspect like
why
why talk about the heart and love
my thought would be that is because
the heart was seen as the most important
organism it would be like the origin of
life comes from the heart the originator
of life and the way you figure that out
from sort of an ancient perspective
is uh when you stab things
what is likely to lead to issues it's
like it's possible to imagine that the
brain is not as special as we might
think
from
when you don't understand modern biology
or um physiology or neuroscience all
those kinds of things especially because
pain
you know is painless too
uh if you stab it
the brain i mean yeah um
yeah anyway so that's that's really
interesting i'm sure there's a
there's a kind of a poetic answer to
maybe the way people wrote about it but
what to you is
the wisdom in the design of the heart i
mean the main function of the heart
basically is to push blood through the
cardiovascular system through the
branching
blood vessels to feed every cell in the
body you know when our i believe our
ancestors started off as single-celled
organisms floating in some ancient brew
and they were surrounded by the medium
that would bring them all the nutrients
they needed so there's no issues there
and then once you start getting
multicellular organisms the kind of that
are thicker and the ones on the inside
aren't in contact with that sort of
nutritious brew that they're growing in
you kind of need a way to distribute
those nutrients to every cell and so
that's what the heart and the branching
vascular tree do so the heart you know
it's i the most the biggest disconnect
between how the organs talked about in
poetry and through history versus his
actual function is probably the heart
because we ascribe all these things like
love and passion
and life itself sometimes to the heart
but actually it's just a simple
mechanical pump you know that's all it
is
i don't want to downplay it it's amazing
but um you know it just pushes it fills
the blood and then squeezes it fills the
bone squeezes it and just that squeezing
that pushing creates the blood pressure
that you need to get blood to every cell
in your body especially when you're
standing upright to get blood to your
brain you need a certain amount of
pressure to get it up there
isn't it
amazing to you how much volume of blood
just gets pushed through by this
by this pump
absolutely they say every red blood cell
takes about five minutes to circulate
and come back to the heart um and that
circulation kind of you know starts at
in the womb and continues and kind of
until the moment that we die
but the volume is tremendous and it can
never
see you know take a break basically and
it's sort of uh
propagating all kinds of stuff
throughout the body it's a delivery
mechanism blood for all kinds of good
stuff and bad stuff nutrition
drugs
all that right medications too
medications
such a fascinating design and it also
takes the waste away you know it kind of
brings the nutritious stuff brings the
nutrients especially oxygen but many
other things and then it also
as it passes the cell takes the cell's
waste so it's sort of the the fresh
water and the sewage system in one so
about blood
what what to use fascinating about blood
so we talk about the pump that spreads
the blood but the blood itself right so
the blood itself is sort of i mean it's
the most important bodily fluid of
course it you know from moment to moment
every cell in the body needs a flow of
blood
um to bring it most importantly oxygen
but also again all the other nutrients
and to take away waste and if that stops
for even a few moments you can be in big
trouble
so blood is sort of you know the the
most important medium it's also doctors
use it to kind of evaluate the body it
does have this kind of all-seeing
quality to it where um you know we can
evaluate organs through the blood i can
tell you about your liver your heart
your kidney just by taking a sample of
your blood
so it's sort of like this crystal ball
in a way and we use it kind of all the
time you know to assess someone's health
to assess their disease
is it also the attack vector for
diseases for bacteria for viruses and
all that kind of stuff so viruses seem
to attack either the throat maybe you
can correct me but they seem to attack
different parts of the body
depending on how easy it is to access
and how easy it is to uh
get in deep
depending on what you prefer if you want
to do a little bit of hard work
but you get in deep or you don't want to
do the hard work
but you don't get in deep those are the
choices viruses have but is blood one of
the sort of
attack factors what's like if you were
trying to break into the human body
uh
like a parasite a virus a bacteria
how would you do it like what would you
what would be the attack vectors you
would explore right so you got to look
for the body's weaknesses of course
um you know we have inherent weaknesses
for instance like our respiratory tract
we have to breathe we have to get air in
from the outside and so that's one of
the entries into the body and so you
know when we inhale let's say a
poisonous gas you know it's it's an easy
way in you have to breathe can't hold
your breath very long but you know air
in our lungs is still kind of contiguous
with the external atmosphere it's not
really inside the body until it does
cross across the lining of the alveoli
into the blood as you said that's when
it really gets inside and the other
besides the respiratory tract the
gastrointestinal tract is another way
kind of a in the armor you know we
have to eat we have to drink and
therefore we're taking the external
world into ourselves into our gut in
order to extract from it what we need
and let the rest kind of flow out
so those two the gastrointestinal and
respiratory tract you know there's a
reason that you know respiratory tract
infections
and gastrointestinal infections are kind
of the most common that afflict us
because those are the ways in to the
body so i would definitely pick one of
those
not just be a lazy cold in the nose but
really a more aggressive pneumonia down
deep in the lungs and get across that
barrier into the blood
but also
the whole sex thing
uh that humans do
so
speaking of which let us go for time
to the genitals chapter
so uh what are genitals i think i've
heard of those
i think i've read about a penis and a
vagina can you explain
to me how those work just asking for a
friend but also
um what do you use fascinating about it
and maybe what's
misunderstood or little known about them
sure so i'm they're very unique organs i
would say one of the things that i like
to point out is that you know while
every organ from moment to moment keeps
us alive and ensures our survival the
genitals are in a way the opposite you
know
we don't need them from moment to moment
you don't even have to use them at all
um and in fact they often make us do
stupid things that are the opposite of
kind of enhancing survival so
and they you know they've affected the
brain and you can become sort of focused
and nuts based on those desires that
kind of stem from the genitals so they
can be dangerous organs too um but you
know i mean sexual dimorphism helps with
genetic variability um as it does in so
many other organisms you know you take
two people and mix them together their
genetics you just get a lot more
variation and more opportunities to try
different genetic codes and see what'll
enhance survival as we talked about sex
and death
i talk about in the book a lot of for
instance the female genital tract how
the uterus is very unusual because you
know it doesn't even sort of wake up and
start doing its thing until the second
decade of life you know it's um even
though
uh babies uh baby female babies are born
with all of the eggs they'll ever have
in their ovaries already they're just
sort of in this stasis until they start
waking up uh kind of once a month
and it's this this cycle you know
there's so much in our bodies that are
cyclical and rhythmic the heartbeat the
breathing
but menstruation is kind of the a very
strange rhythm that takes over a decade
to start
and only you know the rhythm beats once
a month which is very slow compared to
every other rhythm of the body the other
unusual thing is you know in in medicine
when rhythms of the body cease when they
stop those are emergencies right when
your heart stops that's a cardiac arrest
you need cpr maybe an electric shock to
restart it when your breathing stops you
know you need a breathing machine to
breathe for you or something to reverse
whatever might be causing the
suppression of your breathing but when
the menstruation stops it's the point of
menstruation in the first place
the whole reason that the uterus grows
the lining and sheds it each month is to
one day you know
get
get fertilized fertilization for to
implant in the lining and then the
rhythm ceases and that's obviously not a
medical emergency unlike most other
rhythms you know cessations it's the
point of the whole thing in the first
place so these particular
penis and vagina are that whole thing
the uterus whatever am i not using the
wrong terms
i don't know i'll just keep saying you
use those terms there's more technical
there's parts various various parts in
medical school you learn
every bump and you know every little
part of every little organ and including
the genitals so
i never really uh thought of it this way
as you said
is that most organs are kind of
full-time employees
like uh 24 7 they're doing something and
then there's some organs uh
penis vagina being
uh representative of this they're not
functioning all the time they're only
functioning every once in a while and
then get us to do
stupid stuff or awesome stuff and all
that kind of stuff but they're not
essential for human survival on a second
by second basis
and that the whole cyclical nature of
the human body
how many other cycles are on a monthly
basis like
that far apart that's a that's a
fascinating design that the human body
would do that and wouldn't start
until the second decade a decade of life
it's almost like
what do i want to say there's some kind
of
meta planning going on
like this is the optimal solution for
the sexual selection mechanism
among
uh like somewhat intelligent species
like it's useful to
after the brain has developed
sufficiently long
to now be making sexual selection
decisions like you need time for this
computer this really powerful computer
to load in the info
interesting you also need the body to
develop you know a child simply isn't
big enough to get pregnant and deliver a
you know another baby i wonder if
there's animals in which this happens
much more accelerated pace in different
stages d