Evolution

A British scientist is proposing a mission in order for to track down the 'missing link' between human beings and our closest living relative, the chimpanzee. Dr Sydney Brenner who believes it will be possible to discover the last of our common ancestors in the genes of man and chimpanzee. A comparison of their DNA should reveal the physical characteristics of this ancestor, which it became extinct millions of years ago. Instead of searching for bones or its fossil remains of the mysterious hominid, scientists should be able to reconstruct the humanity's ultimate progenitor by analysing the sequence of genetic letters that make up the DNA of its descendants. 'The time has come,' he says Dr Brenner, 'to use computers to rebuilt a creature from which humans and chimpanzees are both originated.' The DNA sequences of any of two humans differ from each other in one or two letters of every 1,000. In a chimpanzee, the number of differences it rises to about 10. Many of these differences will be neutral since that they occur in positions where they have no effect on what a chimpanzee or human looks like. If we could discover the differences that do count, however, we might be able to reconstruct our common ancestor and so find out what were mutations occurred during the course of evolution to separate the species.

In most lines of the text, there is one unnecessary word. It is either grammatically incorrect or does not fit in with the sense of the text. How many unnecessary words can you find

1. A British scientist is proposing a mission in order
   for
   for
   to track down the
2. 'missing link' between human beings and our closest living relative, the
3. chimpanzee. Dr Sydney Brenner
   who
   who
   believes it will be possible to discover
4. the last of our common ancestors in the genes of man and chimpanzee. A
5. comparison of their DNA should reveal the physical characteristics of this
6. ancestor, which
   it
   it
   became extinct millions of years ago. Instead of searching
7. for bones or
   its
   its
   fossil remains of the mysterious hominid, scientists should be
8. able to reconstruct
   the
   the
   humanity's ultimate progenitor by analysing
9. the sequence of genetic letters that make up the DNA of its descendants. 'The
10. time has come,'
    he
    he
    says Dr Brenner, 'to use computers to rebuilt a creature
11. from which humans and chimpanzees
    are
    are
    both originated.' The DNA
12. sequences of any
    of
    of
    two humans differ from each other in one or two letters of
13. every 1,000. In a chimpanzee, the number of differences
    it
    it
    rises to about 10.
14. Many of these differences will be neutral since
    that
    that
    they occur in positions
15. where they have no effect on what a chimpanzee or human looks like. If we
16. could discover the differences that do count, however, we might be able to
17. reconstruct our common ancestor and so find out what
    were
    were
    mutations
18. occurred during the course of evolution to separate the species.