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Fossil and Fossil Record
Fossils are traces or remains of
prehistoric organisms buried and preserved in organic mater or rocks.
Fossils representing many living groups (extinct or not) have been
discovered by scientists, with ages ranging from three and half a
billion year old to ten thousand year old remains of dead/extinct
organisms.
Fossil records contains evidence and traces of how life has evolved through the times. Paleontologists have recovered and examined the fossil remains of many organisms from the past and this has showed that life was very different from before. The fossil records also show how organisms evolved over time. These studies are also known as stratigraphy.
The earliest fossils were
simple, single-celled, microscopic bacteria known as
blue-green algae.
There is few evidence that change has occurred 
in the life
forms on earth over the next three billion years with the exception
of the cyanobacteria.
The fossil record is incomplete. Only a small proportion of organisms preserved as fossils has been studied by scientists. However, certain forms of life has been studied by paleontologists and these include the horse.
Paleontologists have also been able to recover transitions in form of the lower jaw of reptiles. It has been discovered that the reptile’s jaw contained several bones whereas that of mammals contained only one bone.
Many sceptics believe that the absence of transitional information between apes and humans is sufficient evidence to disprove evolution. However, many creatures discovered by paleontologists have proven to fill the gap between man and Australopithecus, a hominid which lived three or four million years ago with a smaller cranial capacity.