Sounds courtesy Daniel Mennill:
songs, it would seem, are about love. Whether it's a blues singer
a lost love, or the sirens luring Odysseus to the shoals, a good song
a great way to attract the opposite sex.
not news to songbirds, who
crooning and wooing long before Frank Sinatra lamented that he "didn't
stand a ghost of a chance with you."
perform their vocal gymnastics to mark territory and get noticed by
females. Many scientists think the quality of the song tells her about
his health -- since only a healthy guy bird could belt out the avian
of "Lover Man."
hear that female black-capped
more than listen closely. When their fellas lose out in a song
the ladies respond.
with a soothing, "Honey,
hit high C-sharp, but you're still number-one. Come kiss my chicken
takeaway message for the
they step outside the nest
action with another guy! In evolutionary terms, that would guarantee
at least some of her young get top-notch genes.
This, in short, is the message of a new
Daniel Mennill and colleagues at Queen's University, Kingston, Ontario.
Mennill, a graduate student, is interested in how animals make
and especially how birds communicate during mating. Instead of looking
just at two parties, however, he's checking the network thing -- how,
a third party interprets communication between two others.
it eavesdropping, since the
the "conversations" of others.
at the Queen's University biological station and identified high- and
males. As with people, upper-crust chickadees skim off the cream, so to
speak. "At a food source... everybody makes way for the highest ranking
bird," he says.
Male songs during mating season can be
or aggressive, Mennill says. Aggressive
songs copy the pitch of the other guy's song.
contrast, a submissive
song uses a different pitch, giving the first songster some
mating season, Mennill hung
with a laptop and a speaker. He gathered the birds by playing the
When the guys began their mating songs,
used software to identify the frequency, and then issued either an
or a submissive song from his laptop. Weeks later, after the young were
born, he took blood samples and used genetic techniques to determine
kid's biological dad.
genetics told the sordid tale,
"After a high-ranking guy lost a competition because I matched and
his song, his female engaged in extrapair copulations." To Mennill,
proves that the females are eavesdropping on the guy-to-guy discussion.
songbirds were once
-- they hang out in couples, and all of the young in the nest of a
male are normally his -- their behavior actually has elements of Beach
Blanket Bingo. Many females do a certain amount of stepping out on
the lady heard her guy
computerized song, about half of her future young wound up having a
dad, Mennill reports. "She's accustomed to hearing him win every song
but after hearing him lose, she changes her reproductive strategy."
it took only six
day, on two successive days, for the
songs to change the female's mind, says Mennill. Apparently "the kind
information available through eavesdropping has a lot of importance
to reproductive strategies."
overlapping and matching songs
uses, says Mennill. "Most animals, including chickadees, live in
where many males are singing at the same time. You have to have
to address one individual if you want to say 'Hey you, I want you out
the story: Guys, if you want
the ladies, tune up those vocal cords,.