Theories of the Extinctions of the Dionsaurs:
Dinosaurs became extincted 65 million years ago, at the end of the
Cretaceous period, something so devastating that it altered the course of life on earth. It
seems like it happened so sudden, as geologic time goes, that almost all the dinosaurs
living on earth disappeared. So how did these dominant creatures just die off? Was it a
slow extinction, or did it happen all of the sudden? These questions bring rise to many
different beliefs on how the dinosaur disappeared over 65 million years ago.
Extinction is when the birth rate fails to keep up with the death rate, it is
called extinction. But, the definition does not answer the question about the nature or
causes of extinction. Paleontologists generally divide extinctions into two types, for that
of different causes arose. The first is called background extinctions, isolated extinctions
of species due to a variety of causes. Included is out competition, depletion of resources
in a habitat, changes in climate, the development or destruction of a mountain range, river
channel migration, the eruption of a volcano, the drying of a lake, or the destruction of a
forest, grassland, or wetland habitat. The second type of extinction is called mass
extinctions. Large numbers of species go extinct; many types of species go extinct; the
effects must be global, and the effects must occur in a geologically short period of time.1
The dinosaur could not have lived for ever. No creatures, no plants, no tiny bacteria are
forever, not even Homo sapiens. Extinction is the fate of all species. One theory on how
the dinosaurs became extinct is that of carbon dioxide, and the greenhouse effect.
Volcanoes produced the proposed conditions. A massive volcanic eruption could have
saturated the atmosphere with carbon dioxide so that it caused a sharp rise in
temperatures worldwide. The excessive carbon dioxide would have permitted solar
energy to enter the atmosphere but would have blocked the radiation of most surface heat
back out into space, therefore causing the greenhouse effect. Rising temperatures could
have killed off or reduced the activity of plankton, disrupting food chains and also
messing up the plankton’s normal role in converting carbon dioxide to oxygen through
photosynthesis. From there it would not have been long for all the dinosaurs to have been
suffering, and then to become extinct.
My theory of the extinction of the dinosaurs is the theory of the comet
hitting the earth. The reason why is believe this is that it seemes reasonible to me. The
comet most of caused flooding and a big cloud of smoke that would lead to know sun.
The dinosaurs probably died from being froozen because of no sun.
The proof the comet theory of the dionsaurs is a huge creator it left in Mexico. The
creator is about mile long. It must of been such a impact that it caused the death of most
of the dinosaurs. Other dinosaurs died from no sun which made the freeze to death.
Today there are still very good theories in which the dinosaurs died. It has been
a mystery for a long time for which one is correct are al of them are incorrect. We will
never really be sure how the dinosaurs died. It had been over 100 years we known about
the dinosaurs and still today we do not know the truth in which they died.