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What happens to our bodies after we die? - Farnaz Khatibi Jafari

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    Since the dawn of humanity,
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    an estimated 100.8 billion
    people have lived and died,
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    a number that increases by about
    .8% of the world's population each year.
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    What happens to all
    of those people's bodies after they die
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    and will the planet eventually
    run out of burial space?
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    When a person's heart stops beating,
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    the body passes through several
    stages before it begins decomposing.
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    Within minutes after death,
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    the blood begins settling in
    the lower-most parts of the body.
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    Usually eight to twelve hours later,
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    the skin in those areas is discolored
    by livor mortis, or post-mortem stain.
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    And while at the moment of death
    the body's muscles relax completely
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    in a condition called primary flaccidity,
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    they stiffen about two to six hours later
    in what's known as rigor mortis.
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    This stiffening spreads
    through the muscles,
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    and its speed can be affected by age,
    gender, and the surrounding environment.
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    The body also changes temperature,
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    usually cooling off
    to match its environment.
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    Next comes decomposition,
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    the process by which bacteria and insects
    break apart the body.
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    Many factors affect
    the rate of decomposition.
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    There is, however, a basic guide of the
    effect of the environment on decompositon
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    called Casper's Law.
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    It says that if all other
    factors are equal,
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    a body exposed to air decomposes twice
    as fast as one immersed in water
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    and eight times as fast
    as one buried in earth.
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    Soil acidity also greatly
    affects bone preservation.
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    High-acidity soils with
    a pH of less than 5.3
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    will rapidly decompose bone,
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    whereas in a neutral or basic soil
    with a pH of 7 or more,
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    a skeleton can remain in relatively
    good condition for centuries.
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    Different cultures throughout history have
    developed unique approaches to burials.
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    As far back as
    the first neanderthal burials,
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    death was accompanied by rituals,
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    like the positioning, coloring,
    or decorating of corpses.
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    Traditional Christian burials decorate
    the body in dress,
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    while in traditional Islam,
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    a body is wrapped in a piece
    of ritual fabric
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    with the face oriented toward Mecca.
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    Traditional Hindus ceremonially burn
    the body,
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    and Zoroastrians, followers of one of the
    oldest monotheistic religions,
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    traditionally place bodies atop a tower
    to expose them to the sun
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    and scavenging birds.
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    Before the Industrial Revolution,
    burials were simple and accessible.
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    These days, with suitable burial land
    running out in high-population areas,
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    purchasing private gravesites
    can be costly,
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    and many people can't afford
    simple burials.
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    Even cremation, the second most common
    burial practice in the world,
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    comes with a high cost.
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    As for the question of running of space,
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    the issue isn't so much about total land
    in the world
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    as it is that large populations cluster
    together within cities.
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    Most of the big cities in the world
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    may run out of suitable burial grounds
    within a century.
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    For London, it's even sooner.
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    That may happen by 2035.
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    So are there alternatives
    to traditional burials
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    that might help with the space issue?
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    In some countries, skyscraper cemeteries
    enable vertical burials.
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    Some options focus on the body's
    relationship with the environment.
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    Promession, for example, freeze-dries
    and pulverizes the body,
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    creating a powder
    that can turn into compost
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    when mixed with oxygen and water.
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    There are also green burials that use
    special materials,
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    such as biodegradable caskets,
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    urns that sprout trees,
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    and burial suits that grow mushrooms.
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    Eternal reefs take that concept
    to the depths of the ocean
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    using a mixture of ashes and cement
    to create marine habitats for sea life.
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    Death is an inevitable part
    of the human condition,
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    but how we treat bodies at burials
    continues to evolve.
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    We may each have different spiritual,
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    religious,
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    or practical approaches to dying,
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    but the ever-increasing demand
    for burial space
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    might give us a push to be creative
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    about where our bodies go
    after the final stages of life.
Title:
What happens to our bodies after we die? - Farnaz Khatibi Jafari
Description:

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Video Language:
English
Team:
closed TED
Project:
TED-Ed
Duration:
04:41

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