The Mine Bird
The mine bird, Serinus
canaria mei, is a close relative
to the domestic canary, and is estimated to split off from his cousin
less than two hundred years ago. Nowadays, it is not uncommon to come
across them in abandoned mines, and sometimes even natural caves.
Descendants
of escaped canaries that the miners would take with them, they had to
adapt rapidly to survive in their harsh new environment, and this has
affected some of their phenological traits in a shocking fashion.
Their
feathers have turned completely white, their brightness no longer
able to serve as an indicator of fitness in the dark mines. Even
flight has become almost useless in the narrow shafts, and with an
almost total absence of predators. Mine birds also have significantly
smaller bodies than regular canaries, which is probably due to the
lack of food, and the constantly
warm air which makes thermo-regulation much easier than in a changing
environment. Their song,
having become their only means of communication, has evolved into
astonishingly complex arrangements, and recent studies suggest that
it may have a much more varied role than in domestic canaries, where
it serves mainly as a mating tool.
How
many of these changes are purely phenetic, and how much are of
genetic origin, remains to be determined, and scientists are in the
process of analyzing the birds' genome and comparing it to that of
household canaries. What we do know, however, is that mine birds that
are raised in a lab with sufficient food and light are bigger and
brighter than those found in the wild.
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