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  • One of my favorite things to do on this channel is to get you to look at the world you know

  • in a different way, to take something you thought was ordinary, and show you why it's

  • amazing.

  • Today I'm here in Alaska, and you're never gonna look at beavers the same way again.

  • [OPEN]

  • Ok, so what do most people know about beavers?

  • They chew down trees, and they build dams.

  • But what most people don't know is without beavers, North Americaand much of the worldwould

  • be totally different than it is today.

  • Beavers are one of the ultimate keystone species—a plant or animal so important to an ecosystem,

  • that without it, the whole thing would basically break.

  • Their dams create habitats for dozens of species, filter and purify water, and enrich the soil

  • by trapping sediment and nutrients.

  • Beaver ponds reshape landscapes on such an enormous scale it impacts all other wildlife

  • and vegetation in the area.

  • Earth is home to two beaver species today: one in Europe, and these here in North America.

  • They're the second largest rodents living today, and like most rodents they have big

  • front teeth that never stop growing.

  • Beaver teeth are actually reinforced with iron, and with their enormous jaw muscles

  • they use those teeth to slice through bark and chop down trees.

  • Besides being carpenters, they even play the part of plumbers.

  • When a beaver hears the sound of running water, it drives them nuts, they know the dam has

  • sprung a leak and they have an uncontrollable instinct to go patch it up.

  • Beavers are ecosystem engineers second only to humans, and they stay pretty DAM busy keeping

  • this pond nice and full.

  • Beavers' urge to build can sometimes cause headaches, but NO beavers can be an even BIGGER

  • problem.

  • Before European colonists arrived, there were as many as 400 million beavers in the US and

  • Canada!

  • North America was covered with tens of millions of beaver dams.

  • Imagine between 5 and 30 beavers on every kilometer of stream or river on the whole

  • continent!

  • That's a lotta beavers.

  • But over a few hundred years they were almost hunted to extinction.

  • Beavers were big business.

  • They were trapped for fur, mostly to make hats, but also for sacs on their butts full

  • of castoreum—a pungent substance used in perfumes.

  • The British Hudson's Bay Company even tried to eradicate beavers from the Pacific Northwestv,

  • figuring with no beavers left to hunt, the United States would stop its westward expansion.

  • Wherever pioneers went, they killed every beaver they could find, despite the fact that

  • beavers were responsible for most of the farmland in the West.

  • Populations dwindled from millions to the low thousands.

  • Without beaver dams, huge areas of land are left with less water.

  • hundreds of species (like fish, birds, insects, and amphibians) are left without a habitat.

  • Sobeaver dams are great for other species, but what's in it for the beavers?

  • Why do they build them?

  • For beavers the pond created by their dams is a safe place to build a home, called a

  • lodge, where they raise their young and keep away from predators.

  • Beavers are pretty awkward on land, but they are safe and happy in the water.

  • The entrance to a beaver lodge is underwater, so beavers can safely scoot in and out.

  • Since they don't hibernate, this lets them access underwater food stores even when their

  • ponds are frozen over.

  • Beavers' favorite foods are the leaves and soft outer bark of trees, but like most mammals,

  • they don't digest wood very well, so they eat their excrement to get the most out of

  • a mealuntil it eventually comes out looking like sawdust.

  • A crew of beavers spotted in a pond is usually a family.

  • Beaver couples often mate for life and beaver kits live with their parents for a couple

  • years while they practice their engineering skills.

  • The oldest dams ever discovered are 100,000 years old telling us beavers or their close

  • relatives have been altering our landscapes even before we moved in.

  • And for most of the thousands of years we've lived together, we've lived in harmony.

  • Now that we've realized how important they are, beaver populations are starting to recover.

  • More beavers means more homes for fish and birds, fresher water, and less damage

  • from flooding and forest fires.

  • Beavers feature prominently in the oral histories of North America's First Nations people,

  • even playing a part in many creation myths, which is neat, because beavers really have

  • created much of the landscape we live in, showing us how old and important our relationship

  • is with the smartest thing in fur pants.

  • Stay curious!

  • If you want to see more of Alaska's incredible wild life, watch Wild Alaska Live, a special

  • 3-night live event brought to you by PBS and BBC.

  • Check the description for more info.

  • Beavers are big as rodents go today, but during the Pleistocene, Earth was home to a beaver

  • called Castoroides the size of a black bear.

  • Too bad they went extinct.

One of my favorite things to do on this channel is to get you to look at the world you know

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B2 US beaver north america alaska fur pond north

Why BEAVERS Are The Smartest Thing In Fur Pants

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    Liang Chen posted on 2018/11/23
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