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5组文字，将其分别放回文章原有位置，以恢复文章原貌。 Conservation or Wasted Effort The
black robin (旅鸫) is one of the world’s rarest birds. It is a small, wild bird,
and it lives only on the island of Little Mangere, off the coast of New Zealand.
In 1967 there were about fifty black robins there; in 1977 there were fewer than
ten. (46) . Energetic steps are being taken
to preserve the black robin. (47) The idea is to buy another
island nearby as a special home, a "reserve", for threatened wild life,
including black robins. The organizers say that Little Mangere should then be
restocked (重新准备) with the robin’s food. Thousands of the required plants are at
present being cultivated in New Zealand. Is all this concern a
waste of human effort (48) Are we losing our sense of what
is reasonable and what is unreasonable In the earth’s long,
long past hundreds of kinds of creatures have evolved, risen to a degree
of-success and died out. In the long, long future there will be many new and
different forms of life. Those creatures that adapt themselves successfully to
what the earth offers will survive for a long time. (49) This
is nature’s proven method of operation. The rule of
selection--"the survival of the fittest"--is the one by which human beings have
themselves arrived on the scene. We, being one of the most adaptable creatures
the earth has yet produced, may last longer than most. (50)
You may take it as another rule that when, at last, human beings show
signs of dying out, no other creature will extend a paw (爪) to postpone our
departure. On the contrary, we will be hurried out. Life seems
to have grown too tough for black robins. I leave you to judge whether we should
try to do anything about it. A Some creatures, certain small animals, insects
and birds, will almost certainly outlast (比 ...... 长久) man, for they seem even
more adaptable. B These that fail to meet the challenges will disappear
early. C Detailed studies are going on, and a public appeal for money has
been made. D Both represent orders in the classification of life. E Is it
any business of ours whether the black robin survives or dies out F These
are the only black robins left in the world.