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Definition and pronunciation of niche. Learn about fundamental and realized niches and the competitive exclusion principle.

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Video transcript

hi it's mr. Andersen in this podcast I'm going to talk about this word right here ecological well it depends on where you live some people call it a niche some people call it a niche and some people even call it a niche and so I tend to call it a niche but I think that's kind of an American thing and so whatever we call it it's derived from a French word which simply means nest and so a good way to think about a niche is basically your role in an environment and if we look right here we see a couple of niches being exploited so we've got a rock here and then we've got lichen that's growing on the rock and so I can actually see four species here because lichen is not one species is actually a symbiotic relationship between an algae and a fungus and they can't live by themselves but I can see this green lichen and then I also see this orange lichen growing right here and they're both exploiting a different niche or a different job and so one of the first scientists to come up with a good definition for a niche is this guy George hutchinson I love his hair and I've never been able to figure out what kind of an animal he's holding looks maybe like a cat or a monkey but he defined it as an n-dimensional hypervolume and so that seems like a crazy term so what's he really talking about well he's saying let's put on one side some biotic factor or abiotic factor let's say on this side we put sunlight and on this side we put moisture well this is just a two-dimensional volume and so basically Auraria we would call that and so let's say that you're an organism that likes a lot of light so you could survive there but you don't do well with moisture well then this would be your niche right here and so it would be this area but he says there are so many different characteristics both biotic and abiotic so we can add temperature food predators all those things so if you think of the each of those being a different dimension then you would have this complex n-dimensional hypervolume and it would be this this shape that only a species can fill and none of those species can overlap so we're getting a little deep let me tell you what I'm talking about so let's say we've got the orange lichen and the orange lichen likes a lot of sunlight doesn't do without sunlight but can't stand a huge amount of volume of of moisture now if we look at the green lichen while the green lichen likes more moisture but doesn't do well if we have a whole bunch of sunlight and so basically if we put those in the same area at the same time we're gonna see two niches the first one is your fundamental niche and so your fundamental niche is where you could live and so in other words for the orange one the fundamental niche is going to be this whole area it could live here but when you have the green like and show up it can't it's being out competed by that green and so now we would have to give up this section this actually belongs to the green and so now the realized niche of that orange lichen is just going to be this shape right here and so that's one way to think about a niche another way to think about it is simply its job and so let's say you work in a factory this is in a early Ford assembly line basically each of the workers in here have a specific job or a role within this Factory likewise in a coral reef each of these coral is going to have a different role that they play within that ecosystem and so they're constantly in competition with each other and in fact we have what's called the competitive exclusion principle and that essentially means that you can ever have two different species filling the same niche at the same time a better way to say that is that complete competitors in other words two species that are incomplete competitions it doesn't even exist it's like a fairy tale and so let me tell you a real story of how this actually plays out and so this is a coyote this is a fox and then this is a gray wolf and so we didn't have the grey wolf in Yellowstone Park for a long time and so basically when the grey wolf was gone the coyote arted to fill that role and they started to have weird pack like behavior and they started to do really well fill niches that were at one time filled by the grey wolf as they did that the red fox population actually went down they took a hit and the reason why is that the Coyotes were exploiting that niche well now we reintroduce the grey wolf into Yellowstone Park the grey wolf actually is killing coyotes killing coyotes by the thousands and so when we introduced the wolf into Yellowstone Park almost immediately 50% of the Coyotes were gone and that's because they were in competition for the same food source the wolf and the kayo and so the wolves would target them and kill them and a pack of wolves against a coyote is no competition because Kyle's kind of lived a solitary life they'd simply kill him and so basically what's happened is the Wolves have now taken over that niche it was that was being filled by the coyote as a result now there's less coyotes and so you could imagine that the red fox population is starting to take off and so that's pretty cool right now if you go to Yellowstone Park we've seen selection and so now we're seeing coyotes that are much larger than they used to be and they tend to spend most of their time around the roads so they get protection from humans that's it that's all I've got on the niche and I hope that's helpful