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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
What do you call a scientist who digs for fossils?
A scientist who digs for fossils is called a paleontologist. They study ancient life forms and the history of life on Earth by examining fossils found in rocks.
How can you find out how old the earth is by studying rocks?
No, as even the oldest rocks of the Earth's crust have undergone at least some remelting since the first accretion of the planet.
Modern science usually uses various forms of radiometric dating (uranium-lead, potassium-argon and rubidium-strontium are the methods most commonly used for dating rocks) in an attempt to determine the age of minerals in the earth's crust.
However these will usually be used to find the date of crystallisation of a mineral. Many of the rocks forming the crust of the earth will have been remelted at some point during the geologic history of the early earth which effectively acts to reset the radiometric dating clock.
As such the oldest crustal rocks currently known have been dated as around 4.28 billion years of age in Northern Quebec, Canada, along the Hudson's Bay coast, 40 km south of Inukjuak.
And the oldest terrestrial material discovered on Earth to date is a zircon crystal found in Western Australia within a metamorphic gneiss which was part of the Narryer Gneiss Terrane. It has been dated at 4.404 Ga (4.404 billion years old) although the rock itself is younger than this.
However the Earth is estimated to be 4.567 billion years old. These estimates come from chondritic meteorites found on Earth.
Fossils or organisms that show the intermediate states between an ancestral form and that of its descendants are referred to as transitional forms. There are numerous examples of transitional forms in the fossil record, providing an abundance of evidence for change over time.
How do dinosaurs become fossils?
They die their skin and guts decompose and turn into soil bones and teeth are left turn rock hard lots of dirt covers it as the years pass people dig it up
What conditions are necessary for fossilization?
the answer to this question is.
Tom Holtz referred the person who asked about fossilization processes to any elementary textbook on geology or paleontology to answer this question.My research has shown that secondary mineralization, remineralization, leaching of bone mineral, and biologically-induced mineralization begin very rapidly after the bone is exposed to the environment.
According to the fossil record how many years ago did life first seem to appear on Earth?
The Cambrian Explosion, a period between about 540 and 530 million years ago when many major animal groups appeared in the fossil record. This is when animals first developed hard shells and skeletons, so they became much more easily fossilised.
Nobody is quite sure what caused the Cambrian Explosion, but increased oxygen levels in the air after the melting of a huge ice age around 600 million years ago may have led to an increase in the size of animals in the oceans; in turn they developed skeletons and shells to support their larger bodies. The evolution of predators may have inspired prey animals to develop shells, as well.
We do have fossils before the Cambrian Explosion, but these are simple, soft-bodied, small and rare, so the origins of animals are still shrouded in mystery.
How does the fossil record evidence support the modern theory of evolution?
Answer 1
For Example, You find a fossil of a creature from a certain timeline, then you find the same creature with some changes in a timeline later than the previous and if you have enough fossils you can see how the organism appears at its earliest place in the fossil record( some organisms only appear in the fossil record once they have evolved in a way that makes fossilization possible eg shell, jellyfish are very rare in fossils because they are mostly water) and see the organism change over time into a completely different animal through a series of consecutive glimpses of the creature.
Answer 2
The absence of transitional forms (fossil record) is an insurmountable hurdle for all evolutionists.
Answer 3
The fossil record, with its many diverging progressions of traits and morphological intermediates, illustrates the changing of life forms as they diverge from their common ancestors towards more modern forms, matching seamlessly the nested hierarchies of modern morphology. Even without the fossil record, we would have had a pretty good picture of our evolutionary past - with it, we can give shape to the forms that came before us.
What types of evidence can fossils provide about earth's history?
Fossils provide one body of evidence for evolution and an accurate theory of our phylogeny back to every living organism's common ancestor (because we are all related and so must have come from the same ancestor).
By performing radiometric dating of the surrounding geology where the fossil was found. There are several radiometric clocks that can be used and as many as are possible are used to get an accurate and confirmed age. This allows evolutionary scientists to better understand how we and all other living things have evolved, and allows for comparison with the other bodies of evolutionary evidence (such as genetic clocks and taxonomy).
That we evolved is a fact, the only question evolutionary scientists are asking now is "How?" And we're getting closer to the truth every day. A better explanation can be found on YouTube - search for DonExodusII.
Why is the ginkgo tree sometimes called a living fossil?
the ginko living species look similar to its fossil ancestors
What is unique about ash-fall fossils?
I got this: "Unlike most fossil deposits, which consist of scattered bones accumulated over extended periods of time, the ash bed contains mostly articulated remains with bones still joined together in the proper order." From here: http://www-museum.unl.edu/research/vertpaleo/ashfall.html
What are Two most common types of fossils?
There are a variety of types of fossils. These include cast fossils, mold fossils, petrified wood, as well as fossil fuels.
How do scientists use Carbon-14 to date fossils?
Carbon-14 is in all living things and decays after it dies. It has a long half life (the time it takes for half a sample to decay into another element) and gives a good estimate as to how old something is.
Carbon dating is only effective up to an approximate age of 70,000 years, and is only useful in dating organic matter. Since the vast majority of fossils are much older than this, carbon dating is not particularly useful in dating fossils, but is of great use in archaeology.
How do paleontologists know how old fossils are?
The dating of fossils was originally done by their placement in a geologic column of rock strata. Because of the Law of Superposition, the deeper the stratum, the older it is (in an undisturbed body of rock or sediment). Fossils which were evident in a particular stratum, but missing from other strata were noted as "index" fossils. The presence of these fossils indicated the age of the stratum relative to other layers. The layers of stratum were placed in a geologic column, subdivided, and assigned names based on the presence of different types of fossil organisms.This is the basis of "relative dating" of rock layers and fossils, a dating technique that was in effect until the advent of radiometric techniques in the twentieth century.
How does a fossil come out of the ground?
Typically, fossils appear on the ground due to the erosion of the rock or material that once encased them. The minerals that replaced the fossils might be more resistant to erosion than the surrounding rock, allowing them to remain after the encasement material has disappeared.
Two conditions necessary for fossils to form?
well in your body there are made up of fossils as fossils are formed in hot places and your body is very warm
Fossils found, such as Wolly Mammoths,differ in many ways. Wolly mammoths are the ancestors to the elephants we have living today. The difference? Wolly mammoths are much longer and differ in size. For example, if you had a mammoth and an elephant stand on their hind legs, the mammoth would be taller.
Why is uranium 238 dating better than carbon 14 dating?
Uranium-238 dating is better than carbon-14 dating for dating older geological samples because its half-life is much longer (4.5 billion years compared to 5,730 years for carbon-14). This makes it ideal for dating rocks that are billions of years old, whereas carbon-14 dating is best suited for more recent materials up to about 50,000 years old.
What two methods are used to determine the age of a rock?
The two methods are relative dating and radioactive dating for fossils. I think it's the same for rocks.
Why are there so few frog fossils?
The reason frog fossils are hard to come by is because of the softness of their bones.
When the earth, soil and rocks move underground, their bones are easily destroyed. Which means fossils cannot form as easily.
But saying that, one of the most famous fossils ever recovered is one of a frog, as you can see its facial features, which is rare for a fossil in general, let alone a frog fossil. More about that on the national Geographic website (click here).
