【TED-0620】Sloths! The strange life of the wor...


来自: 我是什么垃圾?(暗黑城市上空的气态污染物) 2019-06-20 11:38:30

标题:【TED-0620】Sloths! The strange life of the world’s slowest mammal
  • 我是什么垃圾?

    我是什么垃圾? (暗黑城市上空的气态污染物) 2019-06-20 11:40:35


    Well, I'm here to talk to you
    about my animal muse:

    the sloth.


    I've been documenting the strange lives
    of the world's slowest mammal

    for the last 10 years.

    I still remember the first time I saw one.

    I was fascinated by their freaky biology.

    I mean, what's not to love
    about an animal that's born

    with a fixed grin on its face?


    And the need to hug.

    Audience: Awww.

    But sloths are massively misunderstood.

    They've been saddled with a name
    that speaks of sin

    and damned for their languorous lifestyle,

    which people seem to think
    has no place amongst the fittest

    in the fast-paced race for survival.

    Well, I'm here to tell you
    that we've got this animal all wrong --

    and how understanding
    the truth about the sloth

    may help save us and this planet
    we both call home.

    I traced sloth-based slander

    back to a Spanish
    conquistador called Valdés,

    who gave the first description of a sloth
    in his encyclopedia of the New World.

    He said the sloth was

    "the stupidest animal
    that can be found in the world ...

    I have never seen such an ugly animal
    or one that is more useless."


    Tell us what you really think, Valdés.


    I'd like to have a word
    about Valdés's drawing skills.


    I mean, what is that?


    I've never seen an illustration
    of a sloth that's more useless.


    But I mean, on the plus side,

    he has given the sloth
    a remarkably humanlike face,

    and sloths do have remarkably
    humanlike faces.

    This sloth I photographed in Costa Rica,
    I think looks a lot like Ringo Starr.


    But then, sloths do bear an uncanny
    resemblance to the The Beatles.


    Particularly pleased
    with Paul, actually, on there.

    But like The Beatles,
    sloths are also extremely successful.

    They come from an ancient line of mammals,
    and there were once dozens of species

    including the giant ground sloth,
    which was the size of a small elephant

    and one of the only animals big enough
    to eat avocado pits whole

    and disperse them.

    So ...

    Some of you have worked it out already.


    That means that without sloths,

    there might be no avocado on toast today,

    leaving hipsters everywhere
    totally bereft at breakfast.



    Today, there are six surviving species,
    and they fall into two groups.

    You've got your Bradypus
    three-toed sloths,

    they're the ones with the Beatles haircuts
    and the Mona Lisa smiles.

    Then, there are the two-toed sloths.

    They look a little bit more like a cross
    between a Wookiee and a pig.

    They live in the jungles
    of Central and South America,

    and they're extremely prolific.

    There was a survey
    that was done in the 1970s

    in a Panamanian tropical forest

    that found that sloths were the most
    numerically abundant large animal.

    They took up one quarter
    of the mammalian biomass.

    Now, that's an awful lot of sloths

    and suggests they're doing
    something very right indeed.

    So what if, rather than deriding
    the sloth for being different,

    we tried to learn from it instead?

    We humans are obsessed with speed.

    Busyness is a badge of honor,

    and convenience trumps quality
    in our quest for quick.

    Our addiction to the express life
    is choking us and the planet.

    We idolize animals like the cheetah,
    the "Ferrari of the animal kingdom,"

    capable of doing naught to 60
    in three seconds flat.

    Well, so what?



    So what?

    The sloth, on the other hand,

    can reach a leisurely 17 feet a minute

    with the wind behind it.


    But being fast is costly.

    The cheetah is speedy,
    but at the expense of strength.

    They can't risk getting in a fight,

    so they lose one in nine kills
    to tougher predators like hyenas.

    No wonder they're laughing.


    The sloth, on the other hand,

    has taken a more stealthy
    approach to dinner.

    They survive by capturing and consuming

    static leaves.


    But you see, leaves don't want
    to be eaten any more than antelope do,

    so they're loaded full of toxins
    and very hard to digest.

    So in order to consume them,

    the sloth has also
    had to become an athlete --

    a digesting athlete.


    The sloth's secret weapon
    is a four-chambered stomach

    and plenty of time.

    They have the slowest
    digestion rate of any mammal.

    And it can take up to a month
    to process a single leaf,

    which gives their liver plenty of time
    to process those toxins.

    So, sloths aren't lazy.

    No, they're busy.



    Yeah, really busy.


    Hard at work, that sloth,
    very hard at work.

    And of course, leaves
    have little calorific value,

    so sloths have evolved to spend
    as little energy as possible.

    They do about 10 percent of the work
    of a similar-sized mammal

    and survive on as little
    as 100 calories a day,

    thanks to some ingenious adaptations.

    The Bradypus, three-toed sloths,

    they've got more neck bones
    than any other mammal,

    even a giraffe.

    Which means they can turn their head
    through 270 degrees

    and graze all around them,

    without having to actually bother
    with the effort of moving their body.


    It also means that they are
    surprisingly good swimmers.

    Sloths can bob along in water

    three times faster
    than they can move on land,

    kept afloat by ...

    trapped wind.


    So --


    sloths are the only mammal that we know of
    that don't do flatulence.

    When they need to expel gas,

    it's actually reabsorbed
    into their bloodstream

    and expelled orally
    as a sort of mouth fart.


    Turning their lives upside down
    saves further energy.

    They have about half the skeletal muscle
    of a terrestrial mammal.

    They don't really have so many
    of the extensor muscles

    that are the weight-bearing muscles;

    instead, they rely on retractor muscles
    to pull themselves along.

    They have long, hooked claws
    and a high fatigue resistance,

    so they can literally hook on and hang
    like a happy, hairy hammock

    for hours on end.

    And sloths can do almost anything
    in this inverted position.

    They sleep, eat and even give birth.

    Their throat and blood vessels
    are uniquely adapted

    to pump blood and to swallow food
    against the force of gravity.

    They have sticky bits on their ribs

    that prevent their enormous stomach
    from crushing their lungs.

    And their fur grows
    the opposite direction,

    so they can drip dry
    after a tropical drenching.

    The only problem is,
    if you turn a sloth the other way up,

    gravity removes its dignity.

    Audience: Awww.

    They can't hold themselves upright.

    And so they drag their bodies along
    as if mountaineering on a flat surface.

    And I think this is why
    the early explorers like Valdés

    thought so poorly of them,

    because they were observing sloths
    the wrong way up and out of context.

    I've spent many happy hours
    mesmerized by moving sloths.

    Their lack of muscle hasn't impeded
    their strength or agility.

    Nature's zen masters of mellow
    move like "Swan Lake" in slow mo --


    with the core control of a tai chi master.

    This one has fallen asleep mid-move,
    which is not uncommon.


    But you're probably wondering:

    How does a dangling bag
    of digesting leaves avoid being eaten?

    Good question.

    Well, this is one
    of the sloth's main predators.

    It's the harpy eagle.

    It can fly at speeds
    of up to 50 miles per hour,

    has talons the size of a grizzly bear's,

    razor-sharp eyesight,

    and that ring of feathers focuses sound

    so that it can hear
    the slightest leaf rustle.

    The sloth, on the other hand,
    has poor hearing, bad eyesight,

    and running from danger
    is clearly not an option.

    No, they survive by wearing
    an invisibility cloak

    worthy of Harry Potter.

    Their fur has grooves
    that attract moisture

    and act as tiny hydroponic
    gardens for algae,

    and they also attract
    a host of invertebrates.

    So they are their own slow-moving,
    miniature ecosystem.

    They become one with the trees.

    And we think that
    their movements are so slow,

    they slip under the radar
    of the monstrous harpy

    as it's flying about the canopy,
    scanning for action.

    Sloths are stealth ninjas,

    and they rarely leave
    the safety of the canopy --

    except to defecate,

    which they do about once a week
    at the base of a tree.

    Now, this risky and energetic behavior
    has long been a mystery,

    and there are lots of theories
    as to why they do it.

    But I think they're leaving surreptitious
    scented messages for potential mates.

    Because, you see, sloths are generally
    silent, solitary creatures,

    except for when the female is in heat.

    She will climb to the top of a tree
    and scream for sex.

    In D-sharp.


    Don't believe me?

    (Sound of sloth scream)


    This and only this note
    will get the male's attention.

    It mimics the sound
    of the kiskadee flycatcher.

    So the female remains covert,

    even when yodeling for sex
    at the top of her lungs.

    Her clandestine booty calls
    will carry for miles across the canopy,

    and males will beat
    a slow path towards her.


    I think scented messages in her dung
    will help send Romeo up the right tree

    so that he doesn't waste precious energy
    scaling the wrong one.

    Sex, by the way, is the only thing
    that sloths do swiftly.

    I've seen them do it in the wild,

    and it's over and done
    with in a matter of seconds.

    But then, why waste precious energy on it,

    particularly after that journey?


    Unlike other mammals,

    sloths don't also waste time maintaining
    a constant warm body temperature.

    Energy from the sun is free,

    so they bask in the sun like lizards

    and wear an unusually thick coat
    for the tropics to keep that heat in.

    Sloths have a freakishly low metabolism.

    And we think that this might be
    one of the reasons

    that they can sometimes
    recover from injuries

    that would kill most animals.

    This sloth recovered
    from a double amputation,

    and I've known sloths
    that have managed to survive

    even power line electrocutions.

    And we now think that a low metabolism
    may well be key to surviving extinction.

    Researchers at Kansas University
    who were studying mollusks

    found that a high metabolism
    predicted which species of mollusk

    had gone extinct.

    Sloths have been around on this planet
    in one shape or another

    for over 40 million years.

    The secret to their success
    is their slothful nature.

    They are energy-saving icons.

    And I founded the Sloth
    Appreciation Society

    to both promote and protect
    their slow, steady, sustainable lives.

    I'm a pretty speedy character.

    I'm sure you've guessed.

    And the sloths have taught me
    a lot about slowing down.

    And I think that the planet would benefit

    if we all took a slowly digested
    leaf out of their book.

    How about we all embrace our inner sloth

    by slowing down,

    being more mindful,

    reducing wasteful convenience,

    being economical with our energy,

    recycling creatively

    and reconnecting with nature.

    Otherwise, I fear,

    it will be us humans that turn out to be

    "the stupidest animals
    that can be found in the world."

    Thank you very much.

    May the sloth be with you!



回应请先 , 或 注册

207 人聚集在这个小组