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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
Why were so few fossils found from the precambrian period?
There are many fossils from the Pre-Cambrian but most are microscopic, single celled organisms. Later life forms became larger but were soft bodied which did not fossilise except under certain conditions.
What are molds and casts preserved by?
Molds and casts are preserved by a solidifying. Wet plaster or other materials dry or cure until solid and hardened.
Why does carbon-14 not use for a index fossil?
Carbon-14 dating is not normally used to date fossils as it is only accurate for the past 60,000 years and most fossils are much older.
It is mainly used by archaeologists for dating bones and wood from historical sites.
Where did Mary anning find the Ichthyosaur?
Mary Anning found the icthyosaur on the cliffs of Lyme Regis off the coast of England when she was about 12 years old. her dog tray found it and she discovered that it was the full skeleton. Lyme Regis's cliffs are made of clay that encased and preserved the bone structure of the animals. i am researching her right now so this is really true- until someone changes it.
The term for dating fossils based on the relative positions of different rock layers is?
Ether the principle of superposition(also called the law of superposition- concept that the layer of sediment that is deepest is the oldest) or stratigraphy which is the study of layers, when using knowledge of when certain species existed and remains of those species while also studying the layers it is called biostratigraphy.
Do fossil records help to date fossils?
Fossil records contain radiation, and the older the fossil is, the less radiation it gives off. Scientists study how much radiation is in the fossil record, and they find out how old the earth is.
C). a narrow time range and a wide geographic range
What is the maximum depth at which fossils are found in the earth's crust?
They are mostly found on, or very near, the surface. They have probably been quite deeply buried at some point ( a lot can happen in, say, 70 million years) but due to tectonic movements and erosion, they finish up where we can find them. If all the Jurassic rocks were buried at about 300m, then our knowledge of dinosaurs would be impressively small.
What types of body part can become fossilized?
Most of the time only the bones can be fossilized due to the fact that all other muscle/tissue are decomposed when they are under pressure.
Where would you most likely find a sedimentary rock such as sandstone?
Sandstone---as exposed rock on the surface of the Earth in tectonically lifted former beach or deltaic deposits. Sedimentary rock---the majority of rock units on the surface of the Earth are sedimentary in nature.
The keyword is 'surface'.
What shark is the common shark fossils?
Only the teeth are found , because a sharks skeleton is made out of cartilage. This results in poor to no fossilization of their skeletons and therefore is rarely found. I hope this is a sufficient answer.
Why are more fossils not found?
Asking why there are more animal fossils presupposes that there are more animal fossils than plant fossils. This is not the necessarily case. Plant fossils are actually much more common than animal fossils. If you consider the distribution of biomass in modern ecosystems, it is clear that plants are the dominant kingdom (e.g if you walk into a rainforest, you see hundreds of trees, but few large animals). This distribution is a necessity for any functioning ecosystem because the plants are primary producers (other species need them for survival).
Lignite, a low grade coal, is composed entirely of semi-compacted plant fossils. It is so common that it is often burned for use as fuel.
This being said, plants also decay faster than animals given the same initial conditions (they do not typically have hard parts like bones), so the percentage of plants that are fossilized should be less than the percentage of macroscopic animals. Since plants so greatly outnumber animals, however, this does not make fossil animals more common.
Addendum:
It matters too whether one is discussing microfossils or fossils large enough to see or whole fossils or merely a fossilized leaf. See related questions.
Plants have softer bodys parts than animals
What do all fossils have in common?
- All fossil fuels are formed deep underground.
- They are all nonrenewable energy sources.
- They are all made of hydrocarbons.
- They all release carbon dioxide pollution when burned.
How does a index fossil tell you how old a nearby fossil is?
Rock is divided into layers (strata). Each stratum (layer) is different from the other, containing differences between them, and this is essential to determine what era does each belong to. For example, one strata could be rich in sea life fossils like mollusks and arthropods, thus one could roughly estimate the layer to belong to the Middle Cambrian period. A stratum rich in leaf and plant fossils, on the other hand, would suggest it to belong to the Devonian period. There's a science that studies strata, and that's stratigraphy. I am obviously explaining this in a very simple way, as there are many other factors to consider, but this is the essential.
How can an index fossil be located at one location but not another?
The rocks in the two areas are appropriately the same age
Describe the first plants to appear in the fossil record?
fish =)
answer 2 In Ediacara, Australia, appear very early soft bodied fossil shapes in the fine shale. These date from 635 Mya to 540Mya. These are thought have appeared soon after emergence from the cryrogenic period of rather chilly Earth's history. They flourished into the pre Cambrian period.
The Burgess Shale beds of N America are also prolific record to very early (pre) Cambrian fossils.
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Even earlier was the emergence of algae, and these have left their mark in India's Vindhya region with dates of 1.6 - 1.7 Gya. (The Earth has an age of about 4.5 Gy.)
We know that the emergence of algae caused a collapse of CO2 and Methane in the Earth's history, and this reverse greenhouse effect pushed the world into a snowball earth condition for perhaps a billion years. The oxygen these early algae produced, oxidized the dissolved iron in the seas, and precipitated it as the 'banded iron beds' of commercial importance today. Portions of these may be analysed for age and O2 content. [Gya = 109 years ago, Mya = 106 years ago.]
The algae survive today, notably as the seaweeds.
What kind of rocks can you find gold in?
Gold is usually found in metamorphic rock but can also be found in sedimentary rock. In deep mines, quartz rock is found in association with gold.
Why can't carbon 14 be used to date material that is older than 75000 years?
The half-life of carbon is roughly 6000 years. That means that every 6000 years, the amount of Carbon halves. Therefore, in a million years, the amount of carbon-14 would be so low that it would be extremely difficult to determine the exact age of the shell. So radioactive elements of longer half-lives, such as Uranium-238(half-life of 4.9 billion years) are used to date older objects.
What is the difference between trace fossils and original fossils?
Body fossils are any fossil that comes from the animal itself. Examples of body fossils are fossilized skin, bone, teeth, claws, eggs, embryos etc.
Trace fossils are any fossil connected to ancient life but not the animal itself. Examples include footprints, teethmarks, nests, gizzard stones, coprolites, burrows etc.
In a lot of ways trace fossils are as important as body fossils. The give us insight into how the animal lived, how fast it walked, what ate what etc.
Where can one buy Fossil watches for women?
I believe Fossil has their own outlet stores and kiosks. You can also find them in stores like Sears and J. C. Penny. I'm willing to beat you can also find them at Nordstrom's. And if you are into online shopping, you can go directly to Fossil's site.
Where are fossils mostly preserved?
Most fossils are found in sedimentary rock, which is the most common type of rock on Earth. Sedimentary rocks form when particles of sediment are deposited by water or wind, and then hardened over time.
Discuss how fossils provide evidence of change from the earliest life-forms to those alive today?
Fossils showing animals of the past display some similarity to animals of today as well as some differences. When we start at the bottom of the fossil record (where all the oldest fossils are) and work our way up through all the rock layers of the different ages in geologic time, we start to notice the changes in the fossils and how they lead up to the animals of today
a. marine invertebrates
b.land plants
c.reptiles
d.prokaryotes
What kind of information can scientists learn from fossils?
Fossils that include bones can indicate the overall size of an animal, and how its structure was adapted for the environment. For plants, archaeologists can determine the general classification and how the plant may be related to modern plants. Fossils can also indicate how similar organisms changed in geographic distribution as later species took the place of earlier ones.
Why can some fossils form in cold temeratures?
OhNo!Are You using a Interatcive Reader-Science 7th GRADE? WELL I DO TOO, that's why i need help :*(LIFE SCience)
well i think its cause the coldness freezes the animals/artifact in rock and or ice The answer is on the top of page 128 Ice and cold temperatures slow down decay.
