Index Fossil Flashcards
Characteristics of Index Fossil
- Easily Recognizable
- Widespread
- Lived for a short period of time.
Changes in populations accumulate over time.
Evolution
The rarest form of fossilization is the preservation of original skeletal material and even soft tissue.
Preserved Remains
Can preserve an entire organism or just part of one. Bones, shells, feathers, and leaves can all become _______.
fossils
Later the space of the mold may be filled with other sediments to form a matching ____________ in the shape of the original organism.
Cast
Fossils form in five ways:
- preservation of original
- remains,
- permineralization,
- molds and casts,
- replacement, and
- compression.
Are organisms that have existed for a tremendously long period without changing very much at all.
Living Fossils
The most common method of fossilization.
Permineralization
Can also reveal clues about past climate.
Fossils
In some cases, the original bone or shell dissolves away, leaving behind a space in the shape of the shell or bone. This depression is called _________.
Mold
After a bone, wood fragment, or shell is buried in sediment, it may be exposed to mineral-rich water that moves through the sediment.
Permineralization
Preserved remains of specific species found in the strata of sedimentary rock.
Index Fossil
Favorable traits that organisms inherit. It develop from variations within a population and help organisms to survive in their given environment.
Adaptations
Two of the most famous examples of soft organism preservation are the:
Burgess Shale in Canada and the Solnhofen Limestone in Germany.
Fossils from some rock beds may show evidence of soft body parts that are not normally preserved.
Exceptional Preservation
Can give us clues about past climates, the motions of plates, and other major geological events.
Fossils
Are organisms that haven’t changed much in millions of years and are still alive today.
Living Fossils
Some fossils form when their remains are compressed by high pressure. This can leave behind a dark imprint on the fossil.
Compression
Are the preserved remains, or traces of remains of ancient organisms.
Fossils
Shows us that present-day life forms evolved from earlier different life forms.
Fossil record
It is the process by which organic matter exposed to minerals over a long period is turned into a stony substance.
Petrified
In some cases, the original shell or bone dissolves away and is replaced by a different mineral.
Replacement
