Dance and the Birds-of-Paradise

It may look wacky, it may look funny, but
these behaviors didnt evolve to be wacky and funny. They evolved through sexual selection by female
choice to be precise choreographed things that these males do time and time again, day
after day throughout their whole lives, specifically to be attractive to females during courtship. Which birds-of-paradise dance? At some level you can say all of them do something
that could be interpreted as a dance. But if you just hold up a pose and stand there
static, while there could be the static-holding dance, I typically think of that not as a
dance but just a pose, and dance is where theres more motion involved or intricate
steps.

Parotias are good examples of dance, not probably
coincidental that theyre also the ones that dance on the ground like theyre on
a dance floor. They look a little bit more like the way humans
dance. When you see something like a greater bird-of-paradise,
or one of the other paradiaeidaes bouncing around, up and down a branch and turning and
pivoting and putting its head down and letting its cascade of feathers fall over its back,
I mean thats clearly a dance. And even something like the wilsons or
magnificent bird-of-paradise, where theyre just doing most of their displays on a small
little sapling and theres not a lot of lateral motion.

Theres just movement up and down the branch,
but there are more parts of it that are definitely more dance-like and less just presentation
than others, especially right before actual mating; where theres a little bit of motion
this way, motion that way, motion this way, motion that way. Small series of things that happen. I would call that a pre-mating dance, even
in that species. One things that a lot of people dont realize
about bird-of-paradise is that theyre not born doing those courtship displays exactly
the way that we see them and admire them as adults.

For the first few years of their life they
probably dont do anything that looks like a courtship display at all. And then at some point in time the young males,
they start going through transitions in their bodies and behaviors where they start doing
rudimentary versions of it. Theyre hardwired from their genes, through
their DNA to start doing courtship displays. But yet they dont have the feathers yet
and they only do rudimentary versions of them.

But they begin to essentially practice them. And they practice them in isolation by themselves. They watch adult males perform the real deal
to actual females and mating. And then yet practice to each other.

One young male plays the role of the female
the other one plays the role of the male. This one practices his display and this one
pretends like its watching and then they switch. And this goes on for hours at a time during
the day, for months out of the year, for many years, in many cases three-four years of this
kind of practice behavior. And so only then, when they transitioned into
their first adult plumage do the start doing this thing that we recognize as the full courtship
display.

So its this incredible combination of learning
behavior and feedback between practicing with your own body movement and the acquisition
of your costume, if you will, and being able to then put those motions into place in the
way that theyre suppose to be; and the genetics behind that, both the behavior and
the feathers. I dont think a lot of people have an appreciation
of thats whats going on in these birds. When were thinking about traits in birds-of-paradise,
or at least the different traits in males that females are keying into and have selected
on in the past, its easy to think of the feather traits, the unusual ornaments, the
shapes, the colors. But I dont think everybody really thinks
of behavior as being a trait just like any other, when in fact it is.

These complex behaviors are parts of complex
sequences of events that are genetic in their origin and yet they also have this component
of being refined and learned, so they have an environmental component. But the thing is thats true for all of
those traits. The feathers dont always grow the exact
same way that theyre genetically wired to because the food wasnt available in
the same way that year. Theres an environmental component to those
things that are easy to understand as traits as well.

So dance is not just practiced but its
actually a genetic adaptation, and literally there are genes for ballerina dance or waggle? Theres a gene for waggle? I definitely dont think we can simplify
it to the point where there is a gene for a waggle or a gene for a psychedelic smiley
face dance. But there are thousands or hundreds or dozens,
some number of genes that are involved in producing those things and they are heritable. And that when a female bird of paradise selects
a male for some component of his display behavior, that his sons inherit that behavior and some
component of it. And they will be more likely to be more similar
in that behavior to their father than to other males, just like they will be in plumage or
shape of their feathers..