Fossils 10.1
Where do most fossils form?
Most fossils form from animals or plants that once lived in or near quiet water such as swamps, lakes, or shallow seas where sediments build up.
How do fossils form?
Most fossils form when living things die and are buried by sediments. The sediments slowly harden into rock and preserve the shapes of the organisms.
molds and casts
fit together like puzzle pieces
petrified fossils
fossils in which minerals replace all or part of an organism
original remains
fossils preserved in a substance such as ice, tar, or amber (tree sap)
Steps to becoming a fossil
>An animal dies and sinks into shallow water. >Sediment covers the animal. >The sediment becomes rock, preserving parts of the animal. >Weathering and erosion eventually expose the fossil at the surface.
trace fossils
provide evidence of the activities of ancient organisms
The fossil record
provides evedence about the history of life and past environments on Earth. The fossil record also shows that different groups of organisms have changed over time.
fossils are usually found in
sedimentary rock
Then the sediments...
slowly harden into a rock and preserve the shapes of the organisms.
extinct
something that no longer exists and will never again live on Earth
evolution
the gradual change in living things over long periods of time
What part of an organism usually leaves a fossil?
the hard part
sedimentary rock
the type of rock that is made of hardened sediment
petrified means...
"turned into stone"
What are the different kinds of fossils?
Fossils found in rock include molds and casts, petrified fossils, carbon films, and trace fossils. Other fossils form when the remains of organisms are preserved in substances such as tar, amber, or ice.
Water carrying dissolbved minerals and dediment may seep into the empty space of a mold.
If the water deposits the minerals and sediment there, the resut is a cast.
Fossils found in a rock include molds and casts, petrified fossils, carbon films, and trace fossils.
Other fossils form when the remains of organisms are preserved in substances such as tar, amber, or ice.
The fossils record provides evidence about the history of life and past environments on Earth.
The fossil record also shows that different groups of organisms have changed over time.
What are two things that scientists can learn from the fossil record?
The fossil record provides evidence about the history of life and past environments on Earth. The fossil record also shows that different groups of organisms have changed over time.
What does the fossil record tell about organisms and environments of the past?
The fossil record provides evidence about the history of life and past environments on Earth. The fossil record also shows that different groups of organisms have changed over time.
What does the fossil record show about how life has changed over time?
The fossil record shows that life on Earth has evolved, or changed over time. Simple one-celled organisms have given rise to complex plants and animals.The fossil record show that organisms have evoloved and many have become extinct.
What are three ways in which the remains of an organism can be preserved with little change?
The tree ways are Tar, Amber, and Freezing.
mold
a hallow area in sediment in the shape of an organism or part of an organism
paleontologists
a scientist who studies fossils
cast
a solid copy of the shape of an organism
scientific theory
a well-tested concept that explains a wide range of observations
carbon film
an extremely thin coating of carbon on rock
paleontologists use fossils to...
build up a picture of Earth's past environment
what fossils can do
help scientists infer how Earth's surface has changed
What can fossils help scientists infer
how Earth's surface has changed. Fossils are clues to what past environments were like
Most fossils form when...
living things die and are buried by sediment.
the most common fossils are...
molds and casts
Most common fossils are
molds and casts.
fossils
preserved remains or traces of living things