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 Detail, Night of the Giant Ammonites, by Ray Troll '81, 1998, pen, ink, and watercolor on paper
"Art can be
considered as a behavior . . . like play, like food sharing, like
howling, that is, something humans do because it helps them to
survive, and to survive better than they would without it."
Homo Aestheticus: Where Art
Comes From and Why
Ellen Dissanayake
'57
I open my hand and the little wren, momentarily startled by its
newfound freedom, flutters quickly to the nearest bush. I stand in
the hot tropical Australian sun and watch as the tiny bird flits
from branch to branch, a black- and red-feathered jewel. I have
just captured this little bird, collected a page full of data and a
blood sample for genetic analysis back in the lab, and added some
colored bands to his legs so that we can identify him later. The
bird pecks quizzically at its leg bands and then lets forth a loud,
twittering song. His mate responds quickly, singing her own song
and then flying over to join him in the shrub. They hop around each
other excitedly, and I smile as I watch them flit away and
disappear into the eucalyptus forest.
I have come here from Pullman to the steamy edge of the
Australian rainforest to study these little birds, known locally as
“red-backed fairy-wrens.” Working with my students and other
collaborators, I am examining some of the mechanisms that help
drive the evolutionary process. For years we have worked to
understand how mating behavior can lead to the evolution of
conspicuous traits, such as bright plumage and song, which are
ubiquitous in the animal kingdom, yet puzzling, since they are
likely to attract the attention of predators and so decrease
survival. This puzzle is particularly vexing in birds such as
fairy-wrens, which are socially monogamous and seem to show little
if any competition for mates.
Our work has revealed a secret world among these little birds.
Genetic analysis has shown that females often mate with males other
than their social mates and that brightly colored males have a
strong advantage in this hidden sexual competition. Thus, males who
are more brightly colored sire more offspring, spreading more genes
to the next generation, and coming out ahead in the game of natural
selection.
But as in any good science, answering one question opens the
door to a host of others. Why do females prefer brightly colored
males? Why do some males nevertheless have drab coloration? And
might this hidden reproductive competition be important somehow to
the process of speciation—that is, the process by which a single
species evolves to become two separate and distinct species? We are
now expanding our research to address these questions, combining
detailed observations of birds in the field, experimental
manipulations of their family groups, and intensive genetic
analyses in the laboratory. As bizarre (or humorous) as it may seem
to my friends and family, I have devoted much of my professional
career to understanding the sex lives of these funny little
birds.
But why am I doing this? Why do I return to these tropical
Australian forests each year to face—or at least ignore—the many
snakes, insects, and horrifyingly large terrestrial leeches? What
compels me to spend so much time delving into the breeding behavior
and genetics of these little birds?
And I’m hardly alone. Why have so many other scientists, many
here at Washington State University, devoted their careers to
studying the genetics of snails and lizards, the evolutionary
history of various plants, the development of beetle larvae, and a
host of other such questions?
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