THE UNIQUE EARTH AND GEOMORPHOLOGY
( Page 4 ) |
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| The Mystery of Water |
| Every one knows that water in the liquid form is essential
for life. But we take for granted the various special properties that
make it possible for water to remain in the liquid state forming our
oceans. Its density, the boiling point and freezing point are all
so ideal. But what is most mysterious is a property called the anomalous
expansion. Every substance contracts on cooling and thus the density
increases. Water also does so till it cools from 100 to 4 degree Celsius.
On further cooling, instead of contracting the liquid expands causing
a decrease in density. Thus water at 4 degree Celsius has a maximum
density. When the water of the oceans or lakes cools down in winter
the water at the bottom of the sea or lake will be at 4 degree. From
the bottom to the surface there will be a temperature gradient from
four to zero degrees. This allows the water to remain liquid at the
bottom even when the surface is frozen. But for this unique property
the densest water must be at zero degree and freezing will start at
the bottom of the oceans and not at the top. This will cause the whole
of the ocean, even if they are a few kilometres deep, to freeze in
a very short time. Once this happens to thaw all his ice and to get
the water back into the liquid form will almost be impossible. |
| Two other properties supplement this one property and
allow the oceans to remain liquid at the bottom even during the worst
of ice ages. One is the fact that water expands on freezing. This
makes ice to float on the surface. Most other substances like iron
expand on melting. In other words, usually the solid form is denser
than the liquid form. If ice were denser than water the frozen ice
would sink to the bottom and soon the whole body of water would be
frozen. Yet another property is the poor conductivity of ice. This
prevents the extreme cold of the atmosphere penetrating to the bottom
layers. These three properties of water – the anomalous expansion,
expansion on freezing and poor conductivity of ice – allow us
to have water in the oceans even in the harshest of winters and prevents
the oceans from freezing completely thereby destroying all the aquatic
life. And life was purely marine for the first 3 billion years or
so. |
| We do not know if there is life elsewhere in the universe
or not. But when every fact is taken into account the probability
of finding life anywhere else is rather very low. We are actually
unique and can be happy and proud of it. I do not in any way imply
that there is no life elsewhere. If there is life anywhere else in
the universe is this going to affect my beliefs? Not at all. The fact
that there are other places with life or intelligent life will in
no way affect our belief in God. It is all the more reason to wonder
at His ways. |
CREATION OF LIFE
AND BIOLOGICAL EVOLUTION ( Page 1) |
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| “Evolution
is the continuing act of creation” |
| Miss Universe |
| Imagine an explorer from outer space entering our solar
system for the first time and observing each planet, first from afar,
then after landing. The most noticeable thing for this explorer will
be that, out of the nine planets of varying sizes, and a host of satellites,
one stands out as the most beautiful heavenly body. One might even
say that only one of these is really beautiful. For all we know, this
could be, and most probably is, the most beautiful of the heavenly
bodies in our entire galaxy or even the entire universe. We all can
be proud of the fact that this singular beauty, this Miss Universe
is none other than our dear Mother Earth - that the most beautiful
planet is our home. The bright color of the sky and of the ocean,
the pattern of clouds that blankets the ‘ big blue marble’,
the forests and grasslands, the coral reefs and lagoons, none of these
are to be found on the others. Any explorer, terrestrial or extra
terrestrial, cannot help but be enchanted by the beauty of the plants
and trees, the leaves and flowers, the birds whose feathers can be
found in all imaginable colours, the variety of the butterflies, the
numerous species of both wild and domestic animals as well as the
topographic beauty of the land section of the earth. If one considers
these things on land beautiful, what is found underwater, the ocean
floor or the coral reefs will appear even more beautiful. |
| What makes the earth different from others of her kind,
what makes our home so beautiful – the secret of her beauty
- can be described in one word: LIFE. It is the presence of life that
makes the earth unique. Without any living things on it, the earth
would be just another vast desert; no grass, no forest, no coral reef;
just a hot or cold, dry or wet, desert - a dead planet. Life makes
all the difference and makes the earth beautiful. |
| What is life? Not easy to answer. We may say that life
is something that makes a dog different from its chain; that makes
a tree different from the soil on which it stands, that makes a man
different from his corpse. That is life, as I understand it. A scientist
may define it rather differently. According to Gerald Joyce, one of
the current authorities in the field of life sciences: “Life
is a self sustained chemical system capable of undergoing Darwinian
Evolution”. Here Evolution means ability for reproduction, mutations
and natural selection. The whole surface of the earth, both land and
water, are full of innumerable varieties of living beings, of all
sizes and shapes, falling under three general categories; animals,
plants and microbes. The one trait common to all these life forms
is their ability to reproduce, some by the simple process of self-replication,
others by sexual reproduction. All the higher forms of life are made
of tissues with special functions and each of these tissues are made
up of tiny units of life called cells. |
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