An Excerpt from Jim
of February 1, 2004
Issued from the woods just south of Natchez, Mississippi, USA
WITH A SONG IN MY HEART
When I added Cindy's waxwing picture to my webpage on programmed and learned behavior in birds, I took the opportunity to review my text there. Here's something I'd written about White-crowned Sparrows (occasionally showing up around here during winters), which got me thinking:
"Even when newly hatched White-crowned Sparrows are kept where they can't hear any kind of bird song, when they're about a month old they begin singing simple notes. This bird babble, known technically as subsong, continues for about two months. When the birds are about 100 days old, their subsong 'crystallizes' into a form that thereafter doesn't change much. The singing of White-crowned Sparrows of this age who have never heard other birds of their species sing is not nearly as rich and pleasant to hear as that produced by birds who have grown up hearing their own species sing. Nonetheless, experienced birders can definitely hear the White-crowned Sparrow element in their song."
Think of it: The power of the genetic code is so great that it enables a bird to sing its song, even if the bird has never heard that song before. Melodies can be passed through the dimension of time encoded in the genomes of living things.
Further down that page I make the point that when a female Canvasback duck is about a year old and builds her first nest, she builds a nest exactly like all other Canvasbacks, even if she has been kept in isolation, and couldn't have learned Canvasback nest-building technique from other ducks.
These facts cause me to wonder to what extent the songs and "nesting instincts" in our human hearts are genetically fixed. Just how much of each of us is any more than what our genes say we have to be?
That's one question that nudged me into this hermit-naturalist's life. The same impulse that made me a Dixieland-loving trumpet player for most of my life sets me to improvising on the fixed melodies inscribed inside me by my genes, and this seems like a good stage on which to try it. .