According to the Longman dictionary of contemporary English fossils are animals or plants that lived many thousands of years ago and that have been preserved, or the shape of one of these animals or plants that have been preserved in rocks. Everything about fossils, the remains (discovered or not), the rock containing the fossils and its strata is known as fossil record. Most of the time fossils are found in sedimentary rocks and sometimes can be found under volcanic ash.
There are two types of fossils which are type one and type two fossils. Type one is about the remains of dead animals, plants or their imprints. These include bones teeth skin impressions, hair, and the hardened shell of an ancient invertebrates and an impression of an animal or plant. This is even if the actual parts are missing. The second type (type two) is something thats made when the animal was living that has hardened into stone also known as trace fossils. These include footprints, burrows, coprolite (poop).
The study of fossils is known as paleontology. This includes their (fossils) formation across the geological time and the phylogeny evolutionary relationships. The minimum age which qualifies a fossil is often 10,000 years and might go to several billion years of age (Ahlberge 354). Since the 20th centurys discovery of radiometric, it has been possible for dating geologist have been able to determine the absolute age of strata and the fossils therein.
Fossils vary in their sizes as some are microscopic such as bacteria and some are as gigantic as the dinosaurs. Usually the mineralized part of the organism will be preserved such as the bones and teeth for vertebrates. For invertebrates the exoskeletons are the part that is preserved. Soft tissues are preserved, but very rarely. Sometimes fossils may include marks that are left behind by the organism during its lifetime such as marks (i.e. Footprints) or feces which are known as trace fossils (Barnosky 109).
Also some fossils may not be seen by the naked eye but which can be detected. These include chemicals that remain behind long after the organism is dead. Fossils age may range from the youngest at the start of the Holocene Epoch (almost 12,000 years ago) which is the youngest to the oldest from the Achaean Eon which means several billion years old (Barnosky 200).
Location
As I have stated above, fossils are mostly found in sedimentary rocks. But it should also be noted that not always do sedimentary rocks contain fossils. The strata of the sedimentary rocks which contain fossils are some kind of layers. The bottom ones are usually the oldest layers and are the most likely to contain fossils. It is very difficult to locate a site which contains fossils if there is lack of knowledge about the fossil sites.
The best and easiest way to locate fossil sites as Benton (73) says, is to ask the nearest (local) museum or through the internet. Freshly exposed rocks are also some of the places to look, like in roads or railway construction sites or mine dumps. River banks, cliffs and other exposed places are also good. Some of the rocks that are found in layers include limestone (contains mainly calcium carbonate), shale (silt and clay), sand stone, ripple marks and mud cracks.
The fossil records are of paramount importance in studying the evolution of the earth and life on it. And since the knowledge of fossil record came to be, people having gathered information through rocks and minerals that have preserved the external forms of organisms or replaced the remains of the organisms (Berta 263). The fossil record will remain to be the focus of paleontologists as they try to understand the earths evolution process and in particular the evolution of man as specie.
Many explanations have been put forward to explain the meaning of fossils and how they came to be where they are when found. In the past most explanations were based o folktales and mythologies. Most of the scientific views about fossils came around during the renaissance. With the discovery of carbon dating the age of fossils can now be accurately determined. But fossilization is not as simple as it is thought to be. This is because most organisms decay very quickly immediately after death. Only if the organism becomes frozen or rests in a place where there is no oxygen (Bolt 89).
And as I have stated above the parts of an organism that are preserved mostly are the hard parts. But in some cases the soft and delicate parts can also be preserved. This happens after burial when the empty spaces within the organism (liquid or gas filled spaces) become filled with mineral rich water in the ground (Ahlberge 500). For this to occur, the organism has to be covered with sediment immediately after death. Some organisms are completely dissolved and destroyed and all that can be found is an organisms shape in the rock which is known as external mold.
This proves that only in some rocks fossils can be found and these are mostly sedimentary rocks which are rich in some types of minerals as I have mentioned before. Thus making the locating process to be somewhat a search for these types of regions where these types of rocks are available. A permission to dig and excavate in these areas could be extremely dangerous and thus permission should be obtained and experts assistance should be sought.
Preservation
This occurs after burial. As I have afore mentioned the empty spaces are filled with dissolved minerals from the ground. Even within the cell walls of cells of plants this process can take place. On a small scale this process can produce very clear and detailed results. The extent of these remains of dead organisms when buried under the ground will later provide the details of the fossil (Benton 345). Those fossils which consist of traces of skins or feathers and soft tissues are forms of digenesis.
Sometimes the bones, shells or tissues are replaced with other minerals. This means that the original material of the organism are completely absent but what is left is the preserved features, a process which occurs gradually. For example a shell is recrystallized after the original compounds of the skeleton are in a different form as from aragonite to calcite.
Another preservation process is compression fossil. This is a fossil that is preserved in the sedimentary rock that has undergone compression physically. Mostly plants are preserved in this way. The reason behind is that this kind of preservation leads to the fossil distortion. Some of the best leaves fossils are found preserved in sediment layers that have been compressed. And because leaves are flat in nature their distortion in very minimal (Bolt 387).
Another type of preservation is bioimmuration where an organism subsumes another and preserves the latter or an impression of it (Berta 181). Mostly its a plant or an animal that cant move about such as bryozoans grows and covers other sessile encrusters. Sometimes these organisms are soft bodied and so it can be preserved and an external mold. This means that the process of fossilization proceeds differently for different kind of tissues and conditions.
Trace fossils as I have mentioned before are the remains that can be detected rather than being seen by the naked eye. These include burrows, eggs and their shells, nests, feces and other impression. They can give insights into the behavior of animals like feeding which can be of great importance.
Those plant and animal fossils whose size is that which cant be analyzed by the naked eye are recognized as microfossils. Microfossils can be complete in themselves or near complete. They are of paramount important as the reservoirs of critical information which can be used to assist in the rock units correlation.
Natural polymers which are found in stratus all over the world even the arctic are known as fossil resin. These are thought to be an adaptation which has evolved over the ages as a protection mechanism from insects. Often they contain other fossil inclusions that are captured by the sticky substance which was also thought to be a seal wounds caused by damage elements. Some of the organisms include fungi, bacteria and other plants and animals. Also arthropods such as insects and spiders and animals like lizards and some fragments of the DNA are preserved in this manner (Benton 79).
Visual patterns of rocks that occur naturally through geological processes are pseudo fossils. Can be easily mistaken for real fossils and are formed naturally in the rocks that are filled with minerals. Living fossils are also included when they are closely identical to those species that have previously known only through fossils. This means that an organism was discovered to exist when its fossil was found, and then the living animal came to be recognized to be closely related to the previously discovered fossil or completely identical. It is almost like the resurrection of an ancient fossil.
Display
After working long and hard to identify, locate and catalog the collection of fossil, then follows the displaying. Here after are some of the basic steps to display fossils. Firstly, brush away the dirt that came with the fossils with a soft brush. These brushes can be bought from supply stores and can be artists brushes or makeup ones can do.
Secondly, the fossils will have to be rid of the excess salt which is mostly for those fossils which are dug on the beach. This can be done by soaking them in water for a few minutes. The water should be cool and the fossils should be allowed to dry. However, this step can be skipped if the fossil is very fragile as it might fall apart.
Thirdly, mend or reinforce the fossils with glue or varnish if need it be. Elmers glue is recommended by most fossil enthusiasts but in case of an extensive process of restoration then experts have to be consulted. It should be recognized that expensive cases for display are not important or necessary. Plain cardboard boxes with lids are just as good for storage. The lid is useful to keep your fossil safe and to provide space for label which is for identification purposes. Lastly mount the fossils in glass or plastic cases ready to show them off.
Fossils as I have pointed out before are organisms that have been dead and buried in the earth for a long period of time. They are found in sedimentary rocks that contain certain types of minerals that help in the preservation of these dead organisms. These rocks can be found in many places on earth and one may locate them by asking or searching through the internet.
These sedimentary rocks can preserve a variety of organisms although the most likely part of the organisms body that can easily be preserved is the hard part like bones and teeth in the case of animals and the exoskeleton of insects especially the parts with chitin which form the type one fossils. Although it is a very rare phenomenon but some soft-bodied organisms are preserved. This happens when the buried organism is filled with underground mineral water.
This underground mineral water fills up the empty places of the organisms body even if the organism is as tiny as bacteria. Sometimes the organism can be preserved by minerals that take up its shape long after it has decayed and disappeared. Plants are also preserved and are best preserved in compressed sedimentary rocks. The way these preservation processes occur is more or less like luck.
As I have mentioned earlier most organisms disappear because of scavengers and bacteria consumes all. But still a lot of fossils have still been found. But in comparison with the billions and billions of organisms which have inhabited the earth over the millions of years then all the museums, university paleontology labs and all the private collectors have dug a just a small percentage of organisms that have been preserved.
Collecting these fossils can be looked upon as a way to gain insights to the past. One can only imagine how it feels to hold a 400-million-year-old organism. The magnitude and greatness of life and the earth is really wondrous. Some scholars think that studying fossils will give us a clue on the origin of life itself and rid us of the confusion of creation.
The fossils may be in a very fragile and full of dirt when dug up from the ground. Before mounting them for display a process of cleaning them and strengthening them is very important and can be very delicate as well. Therefore dusting, brushing, cleaning and sometimes gluing and other complex processes might be needed in order to reinforce the fossil before mounting it up for show.
Fossil hunt is a very interesting venture as it increases the knowledge and insight to the past as well helping in shaping the future. Most scholars are researching on fossils to even understand and prove the theory of evolution according to Darwins theories and others. Thus its my opinion that more and more people will take interest on the field.
There are two types of fossils which are type one and type two fossils. Type one is about the remains of dead animals, plants or their imprints. These include bones teeth skin impressions, hair, and the hardened shell of an ancient invertebrates and an impression of an animal or plant. This is even if the actual parts are missing. The second type (type two) is something thats made when the animal was living that has hardened into stone also known as trace fossils. These include footprints, burrows, coprolite (poop).
The study of fossils is known as paleontology. This includes their (fossils) formation across the geological time and the phylogeny evolutionary relationships. The minimum age which qualifies a fossil is often 10,000 years and might go to several billion years of age (Ahlberge 354). Since the 20th centurys discovery of radiometric, it has been possible for dating geologist have been able to determine the absolute age of strata and the fossils therein.
Fossils vary in their sizes as some are microscopic such as bacteria and some are as gigantic as the dinosaurs. Usually the mineralized part of the organism will be preserved such as the bones and teeth for vertebrates. For invertebrates the exoskeletons are the part that is preserved. Soft tissues are preserved, but very rarely. Sometimes fossils may include marks that are left behind by the organism during its lifetime such as marks (i.e. Footprints) or feces which are known as trace fossils (Barnosky 109).
Also some fossils may not be seen by the naked eye but which can be detected. These include chemicals that remain behind long after the organism is dead. Fossils age may range from the youngest at the start of the Holocene Epoch (almost 12,000 years ago) which is the youngest to the oldest from the Achaean Eon which means several billion years old (Barnosky 200).
Location
As I have stated above, fossils are mostly found in sedimentary rocks. But it should also be noted that not always do sedimentary rocks contain fossils. The strata of the sedimentary rocks which contain fossils are some kind of layers. The bottom ones are usually the oldest layers and are the most likely to contain fossils. It is very difficult to locate a site which contains fossils if there is lack of knowledge about the fossil sites.
The best and easiest way to locate fossil sites as Benton (73) says, is to ask the nearest (local) museum or through the internet. Freshly exposed rocks are also some of the places to look, like in roads or railway construction sites or mine dumps. River banks, cliffs and other exposed places are also good. Some of the rocks that are found in layers include limestone (contains mainly calcium carbonate), shale (silt and clay), sand stone, ripple marks and mud cracks.
The fossil records are of paramount importance in studying the evolution of the earth and life on it. And since the knowledge of fossil record came to be, people having gathered information through rocks and minerals that have preserved the external forms of organisms or replaced the remains of the organisms (Berta 263). The fossil record will remain to be the focus of paleontologists as they try to understand the earths evolution process and in particular the evolution of man as specie.
Many explanations have been put forward to explain the meaning of fossils and how they came to be where they are when found. In the past most explanations were based o folktales and mythologies. Most of the scientific views about fossils came around during the renaissance. With the discovery of carbon dating the age of fossils can now be accurately determined. But fossilization is not as simple as it is thought to be. This is because most organisms decay very quickly immediately after death. Only if the organism becomes frozen or rests in a place where there is no oxygen (Bolt 89).
And as I have stated above the parts of an organism that are preserved mostly are the hard parts. But in some cases the soft and delicate parts can also be preserved. This happens after burial when the empty spaces within the organism (liquid or gas filled spaces) become filled with mineral rich water in the ground (Ahlberge 500). For this to occur, the organism has to be covered with sediment immediately after death. Some organisms are completely dissolved and destroyed and all that can be found is an organisms shape in the rock which is known as external mold.
This proves that only in some rocks fossils can be found and these are mostly sedimentary rocks which are rich in some types of minerals as I have mentioned before. Thus making the locating process to be somewhat a search for these types of regions where these types of rocks are available. A permission to dig and excavate in these areas could be extremely dangerous and thus permission should be obtained and experts assistance should be sought.
Preservation
This occurs after burial. As I have afore mentioned the empty spaces are filled with dissolved minerals from the ground. Even within the cell walls of cells of plants this process can take place. On a small scale this process can produce very clear and detailed results. The extent of these remains of dead organisms when buried under the ground will later provide the details of the fossil (Benton 345). Those fossils which consist of traces of skins or feathers and soft tissues are forms of digenesis.
Sometimes the bones, shells or tissues are replaced with other minerals. This means that the original material of the organism are completely absent but what is left is the preserved features, a process which occurs gradually. For example a shell is recrystallized after the original compounds of the skeleton are in a different form as from aragonite to calcite.
Another preservation process is compression fossil. This is a fossil that is preserved in the sedimentary rock that has undergone compression physically. Mostly plants are preserved in this way. The reason behind is that this kind of preservation leads to the fossil distortion. Some of the best leaves fossils are found preserved in sediment layers that have been compressed. And because leaves are flat in nature their distortion in very minimal (Bolt 387).
Another type of preservation is bioimmuration where an organism subsumes another and preserves the latter or an impression of it (Berta 181). Mostly its a plant or an animal that cant move about such as bryozoans grows and covers other sessile encrusters. Sometimes these organisms are soft bodied and so it can be preserved and an external mold. This means that the process of fossilization proceeds differently for different kind of tissues and conditions.
Trace fossils as I have mentioned before are the remains that can be detected rather than being seen by the naked eye. These include burrows, eggs and their shells, nests, feces and other impression. They can give insights into the behavior of animals like feeding which can be of great importance.
Those plant and animal fossils whose size is that which cant be analyzed by the naked eye are recognized as microfossils. Microfossils can be complete in themselves or near complete. They are of paramount important as the reservoirs of critical information which can be used to assist in the rock units correlation.
Natural polymers which are found in stratus all over the world even the arctic are known as fossil resin. These are thought to be an adaptation which has evolved over the ages as a protection mechanism from insects. Often they contain other fossil inclusions that are captured by the sticky substance which was also thought to be a seal wounds caused by damage elements. Some of the organisms include fungi, bacteria and other plants and animals. Also arthropods such as insects and spiders and animals like lizards and some fragments of the DNA are preserved in this manner (Benton 79).
Visual patterns of rocks that occur naturally through geological processes are pseudo fossils. Can be easily mistaken for real fossils and are formed naturally in the rocks that are filled with minerals. Living fossils are also included when they are closely identical to those species that have previously known only through fossils. This means that an organism was discovered to exist when its fossil was found, and then the living animal came to be recognized to be closely related to the previously discovered fossil or completely identical. It is almost like the resurrection of an ancient fossil.
Display
After working long and hard to identify, locate and catalog the collection of fossil, then follows the displaying. Here after are some of the basic steps to display fossils. Firstly, brush away the dirt that came with the fossils with a soft brush. These brushes can be bought from supply stores and can be artists brushes or makeup ones can do.
Secondly, the fossils will have to be rid of the excess salt which is mostly for those fossils which are dug on the beach. This can be done by soaking them in water for a few minutes. The water should be cool and the fossils should be allowed to dry. However, this step can be skipped if the fossil is very fragile as it might fall apart.
Thirdly, mend or reinforce the fossils with glue or varnish if need it be. Elmers glue is recommended by most fossil enthusiasts but in case of an extensive process of restoration then experts have to be consulted. It should be recognized that expensive cases for display are not important or necessary. Plain cardboard boxes with lids are just as good for storage. The lid is useful to keep your fossil safe and to provide space for label which is for identification purposes. Lastly mount the fossils in glass or plastic cases ready to show them off.
Fossils as I have pointed out before are organisms that have been dead and buried in the earth for a long period of time. They are found in sedimentary rocks that contain certain types of minerals that help in the preservation of these dead organisms. These rocks can be found in many places on earth and one may locate them by asking or searching through the internet.
These sedimentary rocks can preserve a variety of organisms although the most likely part of the organisms body that can easily be preserved is the hard part like bones and teeth in the case of animals and the exoskeleton of insects especially the parts with chitin which form the type one fossils. Although it is a very rare phenomenon but some soft-bodied organisms are preserved. This happens when the buried organism is filled with underground mineral water.
This underground mineral water fills up the empty places of the organisms body even if the organism is as tiny as bacteria. Sometimes the organism can be preserved by minerals that take up its shape long after it has decayed and disappeared. Plants are also preserved and are best preserved in compressed sedimentary rocks. The way these preservation processes occur is more or less like luck.
As I have mentioned earlier most organisms disappear because of scavengers and bacteria consumes all. But still a lot of fossils have still been found. But in comparison with the billions and billions of organisms which have inhabited the earth over the millions of years then all the museums, university paleontology labs and all the private collectors have dug a just a small percentage of organisms that have been preserved.
Collecting these fossils can be looked upon as a way to gain insights to the past. One can only imagine how it feels to hold a 400-million-year-old organism. The magnitude and greatness of life and the earth is really wondrous. Some scholars think that studying fossils will give us a clue on the origin of life itself and rid us of the confusion of creation.
The fossils may be in a very fragile and full of dirt when dug up from the ground. Before mounting them for display a process of cleaning them and strengthening them is very important and can be very delicate as well. Therefore dusting, brushing, cleaning and sometimes gluing and other complex processes might be needed in order to reinforce the fossil before mounting it up for show.
Fossil hunt is a very interesting venture as it increases the knowledge and insight to the past as well helping in shaping the future. Most scholars are researching on fossils to even understand and prove the theory of evolution according to Darwins theories and others. Thus its my opinion that more and more people will take interest on the field.
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