Hi. It's Mr. Andersen and welcome to biology essentials video 40. This is on
information exchange between organisms. And so if you know anything about biology you
know what message these organisms are trying to send to us. It's a go away from us kind
of a message. This is the poison arrow frog. And we saw these when we were in Ecuador.
They produce this coloration because they have skin that produces a toxin. And so if
you were to eat a poison arrow frog and let's say you were a bird. You're going to associate
that toxin with that color. And it's going to tell you to stay away. Flamboyant cuttlefish
is the same way. It produces a neurotoxin. And it produces not only this coloration but
it also can raise the musculature on it and create these really wild looking pictures.
Just google cuttlefish video and you're going to find some crazy stuff. And so again they
have a toxin. And it's a message they're sending to other organisms, don't eat me. Or you'll
die. And so you're associating this color with that. This down here seems to be this
snake seems to be sending the same message. But this one's actually using mimicry. And
so there's an old saying because a coral snake looks like this and milk snake does as well.
And the saying goes, if red touches yellow you're a dead fellow. If red touches black,
you're okay jack. And so since the red is touching the black here, this is just a harmless
milk snake. But if you're like me you're going to stay away from anything that has coloration
that looks like that. Just because you've been conditioned. And so in this podcast I'm
going to talk about information and how organisms use information to communicate. Now in humans,
just talking is a great way that we communicate, send information from one to another. But
again, most organisms don't have the ability to communicate verbally, yet alone through
podcasts. And so I'm going to talk about mechanisms by which they can communicate. They will send
signals. Those signals can be chemical. Those signals can be visual, auditory. And the example
I'm going to give you is how bees have learned to communicate using a waggle dance, it's
called. That signal is going to have a specific behavior. And so, especially in organisms
that want to defend a specific territory. They can actually mark that territory. That
signal is going to have a desired consequence or a desired effect in organisms which pick
up on it. The example I'll talk about is wolves. And then I want to delve a little bit more
deeper and talk about natural selection. It's easy to say this to observe a behavior but
it's sometimes harder to think about well how could this behavior have arisen? And so
I'll talk about courtship behavior in sage grouse and how that's been learned over years.
And how that's been passed down from organism to organism. And then finally I'm going to
talk about how cooperation not only competition, but cooperation is also important in flocking
behavior and how that has arisen through natural selection through years and years and years
and years. And so let's start with signaling. And so if you're a bee you live in a colony.
And you have to go gather nectar. And so you gather nectar from flowers and it's kind of
a hit or miss. So once they get a hit, once they find some nectar, there's actually a
chemical switch in their brain and they associate the time of the day, location of the flower
and where it is. Now if you're a bee when you fly back to the hive, you now have to
send that information to other bees so they can find it. Because the colony is going to
work more effectively if all the bees are able to quickly identify where the flower
is and move in. And ants, they'll leave a chemical message, but in a bee they've got
to fly there so we can't leave chemicals to find that. And so what's the information that
they have to send? Well they have to send where it is, in other words what's the angle
to the flower? And they use the sun. The position of the sun tells them the time of the day.
But the angle with the sun tells them where the flowers are found. And then the other
thing they have to tell them is the distance. And so they've evolved a really cool way to
signal other bees. It's called the waggle dance. And so if you look at a colony of bees
it seems chaotic. But the more you look at it you'll start to see that certain bees are
doing this waggle dance. And so what they'll do is they'll waggle their body back and forth.
And then they'll move in a figure eight. And then they'll waggle their body back and forth.
And then they'll move in a figure eight like that. Now all the other bees are just gathered
around. And they're watching this dance. Because that dance tells them two things. First of
all if you were to draw that angle right here through that dance it actually is the same
angle that we have in relation to the sun to the flower. And so the angle at which they
dance tells them the angle to the flower. And then how do they say the distance to the
flower? Well it's the number of waggles tell them in bee distance how far it is to that
flower. So that's a crazy kind of a way to signal other bees. And so if you're a scientist
how does that occur? Well as we look at other, not bees, but as we look at other insects,
as they return they're also doing some kind of a primordial dance. And that dance is giving
a small bit of information, but it's highly evolved in bees, because they live such a
social life. Okay. What about behavior and how that effects other organisms? Well one
that I'm familiar with here in Montana are wolves of Yellowstone Park. And so once they
reintroduce the wolves in Yellowstone Park they quickly establish territories. And they're
fiercely territorial. Most people don't know this about wolves. If another wolf enters
into their territory all the wolves will kill it. And occasionally that's manifested by
the wolves going into a town and killing all the dogs in that town because they're fiercely
territorial. And they'll team up on them. Here's a group of wolves that are just moving
and they're surveying their territory. Now how do they signal other wolves, "Hey, keep
out." They do that through howling is one way. So they howl to let other wolves know
where they are. But if you look at these, this is after they were introduced in 2002,
these are all the different wolf packs in Yellowstone Park. And they have really clear
lines of territory. And so how do they make sure that other wolves don't come into their
territory? Well they use a signal as well. In this case they will urinate on trees and
that's territorial marking. So what does that urine leave? And we see that manifested in
our dogs. What does it leave? A chemical message. It's not only saying, "Hey, stay out." It's
saying, "This is the wolf I am." "This is the pack I am." So it's sending a lot of chemical
information to other wolves. Grizzly bears will do the same thing. They'll scratch really
high on a tree and other bears can see that. And they know to keep out. And so that's a
great way to signal other organisms of your intent. Next, learned behavior. So how do
we get this learned behavior. And more importantly, that's why I put Charles Darwin here, how
does this evolve over time? So this is another organism that you can watch here in Montana.
It's called the sage grouse. This would be a male sage grouse over here and then this
is a female sage grouse over here. The males will have these pouches that they'll puff
up in the front and make this really cool kind of a noise. And they actually have a
really cool courtship where they'll develop what's called a lek. And so a lek is going
to be an area where the males will just hang out. And I've seen this in Montana. It's really
cool to watch. The males aren't interested in humans. They're just interested in mating.
And so what happens is that male, the alpha male of the sage grouse, will defend this
lek. You'll have some beta males and then some gammas around the outside. But only the
alpha and the beta males are able to mate. And so the females will actually find this
lek. They'll mate with the alpha and then they'll leave on their way to lay their eggs.
And so this courtship behavior in birds is very important because you want to make sure
that you're only mating with an organism that's very close to you. And so there's this ritualistic
way that they mate. In other words a male, a typical bird may have to be the right color.
It may sing the right song. It has to dip its head three times. And the female has to
spin around. They have these really delicate ways of courting. The reason why is that if
you get the courtship wrong, then you have gotten eaten over time. And so by that selective
pressure, we have these really elegant courtship mechanisms. The lek is just a, just kind of
an exaggerated version of that in birds. Flocking is another example of that. These are the
red-billed quelea of Africa. And they'll form these beautiful flocks. And they'll be just
massive. I read on wikipedia that sometimes it will take 5 hours just for a flock of these
to come by. And so what are you getting with a flock? Well you're getting protection. And
so if you look at all of them, each of these birds is looking in a different direction.
And so they are looking for predators. And so it would be really hard to sneak up on
them. And so once these birds started living together, they started living longer. And
also if you were a bird of prey, up here, it's really hard to target one bird when you
see this flock just moving over time. And so there's been this movement toward this
learned behavior of flocking or cooperation. But they did that one generation at a time.
If you didn't fly, you were destroyed of killed. And then those genes for that were killed
with you. Or that behavior was killed with you. And so over time we have this. Now we
see that in wolf packs as well. And the cooperation in humans, you would say as well. It's really
hard to get along with other humans but if you can cooperate you can do really, really
well. And so that's information. That's how it's used by organisms. And I hope that's
helpful.