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  • [♪ INTRO]

  • At first glance, moss might seem kind of boring.

  • You might've even stepped on some during your last walk without even noticing.

  • But hiding beneath moss's plain exterior is a hidden superpower: the ability to heal.

  • And not just in some abstract sense:

  • During World War I, moss was used for packing the wounds of

  • countless injured soldiers, saving lives on the front lines.

  • Mosses contain a number of chemical compounds that

  • help them survive and protect them from being munched on by predators.

  • For example, sterols help them adapt to changing temperatures;

  • amino acids improve their consumption of nitrogen;

  • and antioxidants help them deal with the stressors in their environment.

  • But the presence of these substances also helped mosses,

  • specifically sphagnum moss, come to the rescue in a big way during World War I.

  • At the height of the war, providing enough bandages

  • for British troops was a critical problem.

  • A lot of the cotton wool traditionally used for bandages was being diverted to the

  • manufacture of guncotton, a smokeless, highly flammable alternative to gunpowder.

  • Because British doctors couldn't get enough bandages and sterile supplies

  • to keep wounds clean and covered, soldiers' injuries were becoming infected,

  • leading to sepsis and death.

  • And that's where moss enters the story.

  • People in Germany were already using it to treat wounds,

  • and, soon, so was the British Army.

  • It might seem out of place in a war defined by new technologies like the airplane,

  • but mosses have been used to pack wounds for hundreds of years.

  • And sphagnum moss grows with abundance in both Germany

  • and the United Kingdom, so it became just

  • one more resource to bring to bear during the war.

  • One of the keys to moss's success is its incredible absorbing abilities.

  • Moss is actually 90% dead plant material,

  • and those dead cells help it absorb up to 22 times its weight in liquid.

  • In fact, it performed better than cotton bandages at absorbing blood

  • and the other substances oozing from soldiers' wounds.

  • The other reason sphagnum was so successful as a bandage

  • is because it creates an acidic, sterile environment.

  • The moss's cell walls are built from acidic compounds,

  • up to 30 percent of its dry weight is uronic acid.

  • The acidic nature means the cell walls of the moss have

  • lots of hydrogen ions very loosely bound to them.

  • Because they're connected only through loose chemical bonds,

  • these protons will easily change places with

  • other positively-charged ions in the surrounding environment.

  • And, since that environment, like, say, soil, or the inside of a wound,

  • now has an excess of loosely-bound hydrogen ions, it becomes more acidic itself.

  • Peat bogs are full of sphagnum and this acidifying process is

  • part of what makes them so good at preserving things like bodies.

  • But moss's acidity also creates a sterile environment

  • because it inhibits the growth of bacteria.

  • And that acidity is just one element of moss's sterilizing property.

  • As I mentioned before, mosses contain many substances

  • that are useful in their survival, but they also help prevent bacterial,

  • viral, and even cancerous growth in humans.

  • Researchers have extracted these compounds and shown them to be

  • successful against preventing the growth of multiple bacterial strains,

  • including E. coli, Bacillus, Pseudomonas and Staphylococcus.

  • Bacillus and Staph infections were particularly common during the first world war,

  • as soldiers rarely had the chance to get clean during trench warfare.

  • During the war, moss drives were held in the UK, Canada, and the United States

  • as the demand for bandages soared.

  • In 1916 alone, Ontario provided millions of bandages made exclusively from moss.

  • And by 1918, one million bandages a month were being sent

  • from Britain to hospitals in Europe and beyond.

  • Not only did moss bandages heal soldiers' wounds, they were a renewable resource.

  • Moss could be collected from nearby bogs and,

  • as long as the peat beneath wasn't disturbed, the moss could grow back.

  • Now, we don't use moss as bandages today, in part because we have antibiotics.

  • But also, harvesting moss is a tremendously labor-intensive process.

  • And that's probably for the best, because moss bogs are huge reservoirs

  • of stored carbon that play a major role in keeping our climate stable.

  • If the peat layer is exposed, it can dry out and catch fire,

  • releasing all that stored carbon in the blink of an eye.

  • Not to mention, mosses aren't well-studied or -understood,

  • even though they are one of the oldest and most diverse lineages of plants.

  • The same properties that make them really great at wound healing

  • make them important engineers of ecosystem biodiversity.

  • So the least we can do is protect them,

  • after all, we owe them for all the lives they've saved.

  • Thank you for watching this episode of SciShow!

  • If you want to help us keep exploring the world and making free content like this,

  • one way to do that is by supporting our work on Patreon.

  • Our patrons make SciShow happen!

  • If you'd like to learn more about what it means to be a patron,

  • you can go to Patreon.com/SciShow.

  • And to all our current patrons: Thank you so much.

[♪ INTRO]

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The Hidden Superpowers of Moss

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    joey joey に公開 2021 年 06 月 28 日
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