Biology Of Earth


     Sometime during our lives, we've questioned ourselves at one point just how long
has the earth existed and how did life begin? Our Biology book written by:

Solomon, Berg, and Martin, shows theories that has taught us that earth is
approximately 4.6 billion years old, and the earliest pieces of life form found
was dated back to approximately 3.8 billion years old. This only leaves a time
space of 800 million years between the formation of earth and the creation of
life. Since then, new theories have shown that life may have originated earlier
then they thought. From Bernstein, Sanford, and Allamandolas' article,
"Life's Far-Flung Raw Materials" comes the theory that only about 100
million years after the earliest possible point for earth to support life,
evidence shows that organisms were already flourishing. But with the amount of
time between this, it almost seems impossible, but not if something were to help
the process like space compounds. Christopher Chyba has the leading idea that
these space particles did in fact bring in the planet's water and atmospheric
gases. These space organisms are thought to be responsible for making our earth
habitable by bringing in water and gas molecules which would provide our
atmosphere and oceans. Also, that the space debris was needed to build life and
could have even started the first cellular processes. These space molecules
could have absorbed UV-rays from the sun, helping out the weaker molecules, and
converting the light energy made into chemical food, which is essential for
photosynthesis. Miller showed that the planets first single celled organisms
came from a process of chemical steps which is possible for the building blocks
of life. It is stated that everyday, tons of space dust falls to the earth's
surface, some found containing 50% organic carbon, bringing in about 30 tons of
organic material. So not only do some scientists argue about space particles
bringing in water and gases, but they could also bring in
"ready-made-organic molecules such as the ones seen today. From the
meteorites that hit the earth they were able to find a variety of 70 amino
acids, but only 8 are used by living cells to build proteins. These meteorites
also show such compounds including: nucleobases, ketones, quinones, carboxylic
acids, amines, and amides. Astronomers have seen a variety of these organic
compounds in the universe and more abundantly in clouds. An experiment was done
in a laboratory by Allamandola, where he developed a cloud containing such
compounds seen in meteorites. This provided more evidence towards the theory of
the earlier development of earth. With the presence of such extraterrestrial
compounds like amino acids, quinones, amphiphilic molecules, and other organics,
could have very well made it possible for the development or helping towards the
development of such life processes. In conclusion, it is easier for us to
believe that extraterrestrial compounds were present during the time of this
evolution and that it inhibited the creation of such living organisms. But since
this concept is relatively new there is not enough evidence to determine if such
compounds had anything to do with the development. Why couldn't one say that the
scientists misinterpreted the development of earth and living organisms all
together? This assumption could regenerate all new findings as to when and how
the earth began.