The Thrill of MockingbirdsBy Donna Kay MalloyLast Tuesday, a mockingbird caught my attention as I approached my office building. Usually in a hurry with briefcase in hand, that morning I stopped and gave this bird my full attention. On cue, the mockingbird serenaded me with a rapid succession of birdcalls, each one unique. I wondered was he singing just for me? I was intrigued, but I'm not the only one fascinated by this talented bird. Five states have chosen this songbird as their state bird. In addition to Florida, Arkansas, Mississippi, Tennessee, and Texas have also honored this talented avian. One characteristic that sets the mockingbird apart from other birds is its physical prowess. The mockingbird uses more of the muscles of its syrinx, the vocal organ, than most perching passerines, such as warblers, finches, thrushes, swallows, crows, and larks. A common bird, the mockingbird has adapted to a variety of habitats from farmlands to urban areas. Why the mockingbird was able to thrive in large cities and suburbs while other species suffered was a question professor of biology at the University of Florida at Gainesville, Doug Levy, wanted answered. "The real puzzle in the field of urban ecology is to figure out why certain species thrive around humans," stated Levy. One school of thought is that some species have a greater inborn ability to adapt to their surrounding environment than others. A mockingbird's penchant for singing may be just the note that saved this species from extinction. This species, known as Mimus polyglottos or "mimic of many tongues," has a larger area of the brain devoted to song memory than most other birds. What inspires the mockingbird to sing? Apparently the melodic mimicry trait is a potent aphrodisiac in the mockingbird world. That same melodic mimicry is what saved this stentorian songbird in Harper Lee's famous "To Kill a Mockingbird." After father Atticus Finch (no coincidence here) gives his children air-rifles for Christmas he instructs them that although they can "shoot all the blue jays they want" to, "it's a sin to kill a mockingbird." Atticus' young daughter, Scout, doesn't understand why she can't shoot mockingbirds. Scout asks her friendly neighbor Miss Maudie, who explains that mockingbirds simply provide pleasure with their songs, saying: "They don't do one thing but sing their hearts out for us." Writer Edwin Bruell summarized Lee's symbolism of the mockingbird as representing something harmless and innocent. Although, Miss Maudie wasn't entirely correct. According to an article in the US journal Proceedings of the National Academy of Sciences, it was reported that mockingbirds could remember people who have threatened them and dive-bomb them if they ever see that person again. The article went on to state that an urban population of songbirds ignored most passers-by, but when they recognized people who had approached their nest from days before, they started screeching and swooping at the tops of the offenders' heads. This journal is credited with being the first published account of wild animals in their natural setting recognizing individuals of another species. "We tend to view all mockingbirds as equal, but the feeling is not mutual. Mockingbirds certainly do not view all humans as equal," said Levy. To prove his point, last spring and summer during the mockingbirds' nesting season, Levy instructed volunteer students to walk up to the birds' nests and gently touch the edges of the nest. For the next three consecutive days, the volunteers walked up to the nests and again gently touched the edges. On the fifth day, Levy assigned different volunteers to approach the nests. It was noted that by the end of the study, 10 volunteers had visited 24 mockingbirds' nests, and each time the volunteer wore different clothing and approached the nests from different routes. Video recordings confirmed that the mockingbirds recognized individuals after just two bad encounters, a skill which is rare among bird species, according to Levy. Even pigeons require extensive training to acquire that skill. "Sixty seconds of exposure was all it took for mockingbirds to learn to identify different individuals and pick them out of all other students on campus," stated Levy. Levy suspects that mockingbirds may thrive in urban environments by having good perceptual powers that allow them to cope with the complexities of living in heavily populated cities, such as being able to differentiate between cats that are aware of their nests and those that are simply passing on by. Perhaps the mockingbird that serenaded me that morning recognized me and perceived that I was there only to appreciate the pleasure of his song. In the end, he did sing his heart out for me.
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