Bernie's theory on niche slection for singing seems to be steeped in logic =
as far as our knowledge of natural selection is concerned. Anyone who has r=
ecorded birds internationally (and domestically, as well, although this doe=
sn't give one the wider perspective) will discover in their recordings the =
patterns of species song repetitions. Editing (and, in particular, computer=
editing using any kind of time scale) reinforces this knowledge when we tr=
y to isolate certain species to stand out more to make their voices more di=
stinct. Everything Bernie suggests in the article is consistant to the impe=
rative of how animals using sound must adapt in order to procreate. It is c=
ertainly not far-fetched when one considers the many other natural adaptati=
ons that occur in the name of parenthood. Bernie is simply proposing an exp=
lanation for sound that has already been attributed to plumage and appearan=
ce in more commonly quoted quarters dealing with species evolution.
In an aside to this, I have seen a pattern in birds when it comes to the ty=
pe of song that evolves in a particular habitat. For example, birds that li=
ve close to moving water seem to evolve songs that have similar characteris=
tics regardless of whether it is a forktail in the Himalayas, a Torrent-lar=
k in New Guinea, or a Mountain Wagtail in Africa. Another example would be =
a study of birds that sing in exposed mountain locations where there is gre=
ater sound distance carriage. Most of us in NA know what a Canyon Wren can =
do, but you should hear a Common Hill Partridge or Chestnut-crowned Antpitt=
a deliver their songs from mountainside. I have not had a chance to put thi=
s to the bandwidth test myself as I am still trying to get all my material =
into a computer in the first place, but I was wondering whether anyone has =
published anything on this subject?
Still digging out of the snow,
Scott Connop
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