Hi. It's Mr. Andersen and 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 things. 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. And 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. It's
actually a symbiotic relationship between an algae and a fungus. And they can't live
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. It 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, or area 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 could add temperature, food, predators. All those things. So if you
think of each of those being a different dimension then you would have this complex and dimensional
hypervolume and it would be 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.
It doesn't do well without sunlight. But can't stand a huge amount of moisture. And now if
we look at the green lichen, well 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 going to 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 lichen 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 an 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 corals is going to have a 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 they competitive exclusion principle. And that essentially
means that you can never 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 in complete competition, doesn't even exist. It's like a fairly 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 this is a grey 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 coyotes started to
fill that role. And they started to have weird pack like behavior. And they started to do
really well. Fill niches that were 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
coyote. And so the wolves would target them and kill them. And a pack of wolves against
a coyote is no competition. Because coyotes kind of live this solitary life. They simply
kill them. And so basically what's happened is the wolves have now taken over that niche
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.