Paleontology

Index fossils help scientists figure out the plants and animals that were alive in a certain time period. There are different types of index fossils that are used for different amounts of time.

The rock is most likely slate, which is a fine-grained metamorphic rock composed of clay minerals such as muscovite, chlorite, and quartz. Slate's ability to split into thin sheets makes it suitable for shingles, blackboards, and other applications where a flat surface is desired.

The Proterozoic is a geological eon that spans from around 2.5 billion to 541 million years ago. It is characterized by the appearance of complex life forms, including the first multicellular organisms and the rise of eukaryotic cells. The Proterozoic also saw the formation of vast supercontinents, significant changes in Earth's atmosphere, and the development of oxygen-producing photosynthetic organisms.

Aside from carbon-14, rocks that can be radiometrically dated are mostly igneous and metamorphic rocks. most sedimentary rocks cannot be dated by this method. this is because many sedimentary rocks are made up of particles eroded from older rocks. dateing these pieces only gives the age of the preexisting rock from which it came.

All fossils are non-living. However, they are always created by living things. Fossils are either a form of preserved remains of a living thing from at least hundreds of thousands of years ago (otherwise they are simply remains), or they are the remnants of signs of a living thing from an equally long period ago (footprints, imprints, fossilized dung, etc).

It is difficult to reconstruct the evolutionary history of hominids because the fossil record is incomplete and fragmented, making it challenging to establish direct ancestor-descendant relationships. Additionally, the evolutionary processes that shaped hominid species span millions of years, further complicating the reconstruction of their evolutionary history. Genetic data and other scientific methods can help supplement the fossil record, but uncertainties and gaps still exist.

An index fossil is organisms that is a signature for certain geographical eras. Index fossils are a charting of time that is used to describe other organisms found in that time era. The fossils were found in the stones that are determinations by carbon indexing and therefore are index fossils.

Yes, trilobites were still present in the Permian, but at much lower numbers and diversity. Only the Order Proetida remained.

The Permian ended with a mass extinction, and among the many groups which went extinct at the end of the Permian were the last trilobites.

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The grunge music scene first appeared in Seattle, Washington during the late 1980s and early 1990s. Artists like Nirvana, Soundgarden, and Pearl Jam were influential in defining the grunge sound and gaining popularity for the genre.

The atmospheric conditions during the Moseozoic Era were a warm, moist feel. This type of condition was needed for the gargantuan herbivores to survive. If it was not like this, the Era would most likely be vague and abnormal to us homo-sapiens

Scientists study airflow so that they can better understand it, the air flow can also help with determining the weather. Some scientists also study airflow so we can create better and more efficient cars and transportation.

The percentage of oxygen in air remains fairly constant on a global scale but varies considerably on a local scale. The concentration of oxygen in your lungs is much different as you inhale than when you exhale for example. The concentration of oxygen entering your car's engine is much different than the concentration in the exhaust from that same engine.

The percentage remains fairly constant on a macroscopic scale because of the equilibrium established by the uptake by plants of the carbon dioxide and subsequent release of oxygen through photosynthesis. There is also a substantial amount of oxygen dissolved into the oceans of the Earth which remains in equilibrium with the oxygen in the air. Just based on the scale, it would take an enormous amount of oxygen addition or removal from the atmosphere to make a significant change in the percentage of oxygen in the atmosphere. Such a change would take a very long time to accomplish. In truth, the composition of the atmosphere millions of years ago was different than now - with noticeably higher levels at times and lower levels at other times. It took millions of years for the changes to occur however.

Travelers in the Ordovician time period might face dangers from marine predators such as giant sea scorpions and armored jawless fish. They might also encounter environmental hazards like widespread glaciation and unpredictable shifts in sea levels. Additionally, volcanic activity and tectonic movements could pose risks to travelers during this time.

Can you define more clearly what you mean by 'Strongest'? That can cover a vast number of different categories and there are many different metals which can be considered the strongest, according to your specification.

You should be careful when you find a fossil because they are often fragile and can easily break if mishandled. It's important to handle fossils gently and with care to preserve them for future study and enjoyment. Additionally, some fossils may contain sharp edges or delicate structures that can be easily damaged.

There are two major schools of thought that can provide two entirely different answers to this subject. See the discussion section below for a Creationist's point of view on this answer.

Anyone knowing the current scientific answer to this can feel free to finish off this answer.

When living things die, sometimes they can get buried in mud or sand before they rot away. If this happens, over time the mud or sand can be turned into rock and the hard parts of the living things are also mineralized (turned into rock) but in a way that preserves the structure of the original living thing.

An impression of a living thing preserved in this way is called a fossil and by studying the fossils that are to be found in rocks it is possible to see and understand creatures that lived on earth a very long time ago.

It's happening right now. The human race has or is about to wipe out as many species as the meteorite that hit the planet 65 million years ago and ended the reign of the dinosaurs, which was about 90% of all life on earth.

1. Preservation in sedimentary rock: The organism's remains are buried in sediment and mineralized over time.
2. Casts and molds: The organism's remains decay, leaving an impression in the sediment that is later filled with minerals.
3. Carbonization: The organism's remains are compressed, leaving behind a thin film of carbon.
4. Freezing or desiccation: The organism is preserved through freezing or drying out quickly.
5. Amber preservation: The organism becomes trapped in tree resin, preserving it over time.

Drywall, also known as gypsum board or plasterboard, is a home-building material made primarily from the mineral gypsum. Gypsum is processed and compressed between two sheets of paper to create drywall panels commonly used for interior walls and ceilings in buildings.

Gabbro is usually made up of minerals such as pyroxene, plagioclase, amphibole and olivine which makes it an intrusive igneous rock.

Temperate forests are located in the eastern parts of North America and Asia as well as central and Western Europe. The temperature in these forests fluctuates from -30 degrees Celsius to 30 degrees Celsius.

It was the second largest extinction in terms of loss of life. The extinction was caused by the movement of Gondwana into the south polar region which led to glaciation and subsequent sea level fall. At this time all know life was confined to the oceans and 60% of marine invertebrates died. The event ended when Gondwana moved out of the south polar region, the glaciers melted, and sea level returned to normal.

The main type of rock in oceanic crust is basalt. Basalt is a fine-grained igneous rock formed from the rapid cooling of lava at or near the Earth's surface. It is dark in color and rich in minerals like pyroxene and plagioclase feldspar.

They are valuable because they are rare and take a long time to process to create a good looking stone. They are classified as "gemstones".