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Fossils
This category is for questions about the bones, fragments, imprints, and other remainders from a different time. The questions and answer you will find here are history set in stone -- our past, immortalized in solid rock. You will also be able to find questions pertaining to the locations of these fossils, how you might identify them, and how they were formed.
3,454 Questions
well we could debate the answer that the process of fossilisation is a long one (like mine) or we could debate that the proccess of fossilisation is short (probably like yours) but i think you should just give up with your entire life like i did and dont worry it all ended up good for me
Why are index Fossil helpful for performing relative dating?
Because they give us the best estimate of how old all the other fossils are in that sedimentary layer.
Are there any fossils found in Nevada?
Yes, fossils have been found in Nevada, particularly in areas with sedimentary rock formations like the Great Basin and the Las Vegas Valley. Fossils of prehistoric animals such as mammoths, sloths, and ancient marine creatures have been unearthed in the state.
How does amber preserve insects?
Amber originates as resin (gum) dripping from a tree. Perchance, occasionally, a new drop will fall upon an insect unfortunate enough to be exploring previous deposits of resin. It is thus encapsulated in a very sticky material, and escape is unlikely. Hence the 'preserved insect.
What is the method used to estimate age after something died?
The dating method used to estimate age after something died is the carbon dating method. The carbon dating method measures the half-life of the carbon in the organism.
How does the fossil record support natural selection?
It shows how organisms change slowly overtime.
For example, examination of the inner ear bones of whales show how it changed from being able to hear well on land to being able to hear well in water as it evolved from a land mammal to a mammal that lived both on land and in the water, to one that only lives in the water.
This shows support of natural selection because it would be advantageous for an animal who was spending more and more time in the water to have hearing adapted to hearing in the water.
a.
interpreting past environments
b.
indicating when the rock formed
c.
matching rocks of the same age found in different places
d.
all of the above it would be D
How do the characteristics of an index fossil is useful to geologists?
Index fossils are fossilized remains of organisms that serve as convenient reference points to geologists because they were very widely distributed during a very short period. This means that, if a geologist is trying to figure out how old a certain segment of rock is, the presence of an index fossil will give him a very good idea to a pretty high level of certainty.
Most index fossils are aquatic, especially mollusks. This is because (a) mollusks had shells, which are easily preserved, and (b) marine organisms generally fossilize easily because they often live on sand and so turn into sedimentary rock, which forms without volcanic activity (like igneous) or intense pressure (like metamorphic).
One good example of an index fossil is Paradoxides, a species of trilobite that was distributed in seas all over the world, but only for a very small amount of time during the Cambrian Period, about 540 million years ago.
What prerequisites must be met for most organisms to be fossilized?
Most of the fossils we find were buried in flood sediments. Thus, rapid burial (preferably in an anoxic environment) aids in fossilization. Most of the fossils that ever existed were subsequently eroded away and obliterated by the same river systems where they were created. A second requirement, therefore, tends to be climate change, or some environmental disturbance (such as an earthquake or volcanic eruption) that changes the course of a river system, or gently uplifts a mountain range.
Some fossils, especially insects, are encased in amber. These are exquisitely well preserved, but it requires millenia for tree sap to harden into stone.
Second, for us to find the fossils, they must again erode close to the surface where fossil hunters can stumble across them and recognize them for what they are. Many fossils have been destroyed by people who did not recognize these strange things eroding out of the earth had any value.
There are three types of fossils. There are impressions, such as footprints or body parts molded in clay which subsequently hardened into stone. There is infilling, where calcium carbonate or some other substance fills in the spaces left by decaying organic matter. Both of these types of fossils can be created quite quickly. The last, mineralization, is the replacement of organic material with inorganic material. This replacement occurs over many thousands of years. It is an extremely slow process.
Yes.
One form of fossil forms when an organism dies and its body is covered by layers of sediment. As time passes, the organism itself, particularly when composed primarily of softer materials, is eroded and carried away, leaving a negative imprint of its body. This type of fossil is called a mold. A cast fossil forms when a mold fossil is filled with some form of mineral, usually through the seepage of water depositing the minerals within the mold. In time, the mold is filled and the materials deposited harden, creating a replica of the original fossil. This is called a cast fossil.
What are the most common types of fossils found in Florida?
The most common four types of fossils are:
- mold fossils
- (a fossilized impression made in the substrate - a negative image of the organism)
- cast fossils
- (formed when a mold is filled in)
- trace fossils = ichnofossils
- (fossilized nests, gastroliths, burrows, footprints, etc.)
- true form fossils
- (fossils of the actual animal or animal part).
What was the preserved remains of ancient organisms called?
The preserved remains of animals of evidence of their existence are Fossils
Fosssils that provide evidence about the past are called trace fossils.
Why don't we find fossils in igneous and metamorphic rocks?
Fossils are remains or impressions of living organisms and they are found in the sediments in or near where they lived.
Living organisms cannot live in a molten magma which cools to become an igneous rock.
Metamorphic rocks used to be sedimentary and igneous rocks but they were buried very deep under mountains and any traces of fossils in the sedimentary layers have been removed by the heat and pressure which altered the rock.
Why are the relative and absolute ages so important to a scientist in geology?
It is quicker and can be done in the field for a quick age referencing of a rock sample.
No, it's an igneous rock, made from cooling and consequently solidification of a magma. Animals (or any other organism) capable of leaving behind a fossil can not survive and do not live in a magma.
Fossils can be found in sedimentary rocks or in metamorphic rocks (if the protolith, the original rock, was sedimentary). In metamorphic rocks, fossils are generally intensely deformed and hence difficult to recognise/identify.
Which fossil type could contain preserved parts of a organism?
It is called a mold fossil, which can become a cast fossil.
After the soft parts of the animal rot away, a cavity remains (the mold fossil) which becomes filled with hardened sand or mud (the cast fossil).
What part of an animal is most likely to form a fossil?
A2. The soft parts of an animal are least likely to survive, for these will be degraded by bacterial and insect action, if not by larger scavengers. If an animal dies on the land surface the chances of fossilization are minute.
Good preservation of a fossil depends greatly on the environment in which the animal dies. If it is a very fine-grained silt, the probability of preservation is good, particularly of fine detail. The environment is likely to be anaerobic, and even the body's internal bacterial flora may be unable to survive in an anoxic environment.
One of the remarkable preservations was the Archaeopteryx fossil, on which even the feather detail may be seen. Discovered quite soon after Darwin had launched his Origin of Species.
Unusual preservation localities include swamps, and the remarkable La Brea tar pits. Another unusual fossil preserve is that of insects and spiders preserved in amber originally a gum exudate from trees.
