Invasion Of The Earthworms!
Worms cause major changes to ecosystems, but those changes aren't always new. Thanks to the University of Minnesota for sponsoring this video! http://twin-cities.umn.edu/ Thanks also to...
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Hi, this is Emily from MinuteEarth. Earthworms have earned a reputation as nature's gardeners, because they eat leaves and then poop their way around underground, returning nutrients to the deep soil. But some plants, and even whole ecosystems, are actually better off wormless. For example, for several thousand years, the forests of northern north america grew tall and thick, in part, because there were no worms. Without earthworms to munch fallen detritus, leaves piled up in thick layers, which protected young tree seedlings from frost and herbivores, and also prevented the trees' competitors – smaller, sun-loving plants – from pushing their way through. But, then, in the 1800s, some European wrigglers arrived - perhaps as fishing bait for other ne...
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Hi, this is Emily from MinuteEarth. Earthworms have earned a reputation as nature's gardeners, because they eat leaves and then poop their way around underground, returning nutrients to the deep soil. But some plants, and even whole ecosystems, are actually better off wormless. For example, for several thousand years, the forests of northern north america grew tall and thick, in part, because there were no worms. Without earthworms to munch fallen detritus, leaves piled up in thick layers, which protected young tree seedlings from frost and herbivores, and also prevented the trees' competitors – smaller, sun-loving plants – from pushing their way through. But, then, in the 1800s, some European wrigglers arrived - perhaps as fishing bait for other ne...
