Introduction to the Origin of Species

This and the following pages conform the content included in :
Science Education Key Learning Area, Biology Curriculum and Assessment Guide (Advaned Level), Jointly prepared by the Curriculum Development Council and the Hong Kong Examination Authority 2002

******************************

Syllabus

3.2

Evolution

*	the evidence of evolution : a brief assessment of fossils and homologous structures in pentadactyl limbs. The limitatioins and accuracy of fossil records.
*	the presence of other evidences of evolution, e.g. comparative anatomy, comparative biochemistry.
*	the mechanism of evolution : the roles of genetic variation, natural selection, and isolation in the development of new species.

******************************

Suggested Readings :

(1)	Advanced-level Biology for Hong Kong, by Y.K. Ho, SNP Manhattan Press (H.K.) Ltd. Bk 1, p.
(2)	New Understanding BIOLOGY for Advanced Level, 4th ed., by Glenn and Susan Toole, Stanley Thornes, p.
(3)	A-level Biology, by Phillips and Chilton, Oxford University Press, p.
(4)	Biology : Principles and Processes, by Roberts, Reiss and Monger, Nelson International, p.
(5)	Advanced Biology principles and applications, ISE, by C.J.Clegg with D.G. MacKean, John Murray, p..

******************************

From the beginning of human beings, the origin of life is still a mystry. Different religions, tribes or scientists would prefer different answers. Until now, there is still no one unite and objective answer, and, with proof. The followings are the two uncompromizable hypotheses. Each of them have tremendous supports. Students can learn and make judgement by themselves.

(1) Special creation

General tribes and religions would agree with the doctrine of special creation. Most of them believe that human was the creation of their gods. Different tribes or different religions believe that their gods use different methods to make people. In christianity, it was said that the God made people (Adam and Eve). Their pilgrims believe that people was made under a will or as a practice of a wish. In chinese tradition, it was said that people was made by a god using mud. No matter they mentioned a god or not, they all agree that people was made by a will. Anyway, there was no evidence and no proof. So, these doctrines were religions only. They are not science.

(2) Evolution

At the other end, some people did not agree that people was created by a will. They thought that it was merely a natural phenomenon. Living things occur at the very beginning as simple inorganic molecules. Under the special environmental conditions in ancient world, the simple inorganic molecules proceeded some chemical changes and produced some complicated organic compounds, as proteins or RNA. Eventually, these complicated organic molecules collided and produced the even more complicated masses, and, eventually some forms of simple organisms. This was the formation of lifes. Such hypotheses, stating the production of life by no will, was known as the evolution. Charles Darwin and Alfred Wallace were the frontiers of this hypothesis. As evolution needs billions years to occur. So, there is no chance to carry out experiment or observation. So, evolution cannot be proved scientifically. If it cannot be proved scientifically, then, it is also not a science. It is also a religion. But scientists accepted this as a hypothesis. But this hypothesis can never become a theory or fact, because it cannot be proved.

(3) Origin from outer space

Nowadays, some scientists found that the chance for evolution to occur is almost impossible. But also, they would not like to accept the hypothesis of special creation. So, they just attempt to find the origin or life from the universe. They supposed that in some planets in the outer space, there may be some forms of life. They may enter the Earth occasionally in the form of asteroids. In the past, scientists believed that the high temperature produced during the entrance to the atmosphere of the Earth would burn away all organic matter in the asteroid. So, it is impossible for the life from outer space to enter the Earth. Recently, scientists found in experiments that under some special situation, the asteroids entering the atmosphere just like a piece of baking bread. Its suface can be very hot, but the inside can be rather cool. It can be cool enough to keep the alien organism to survive. So, the entering of alien life onto the Earth is possible. They believed that this form of life can live by the operation of RNA, because, now, it is found that RNA can act as genetic material or enzymes. this form of RNA enzyme is called the ribozyme. Now, this hypothesis is rising. It may be posisble that this hypothesis would become dominant in the near future.

(15.05.2006)