Lecture 2 Flashcards
Paleontology
The study of ancient fossils, the remains of ancient organisms. Combines geology( study of rocks and earth) and biology (study of life)
What is actualism and what is its significance to taphonomy?
Actualism is the principle that the laws of nature have remained constant over time. In taphonomy, it’s the assumption that processes affecting fossils today worked similarly in the past.
What are the three taphonomic stages
• Biostratinomy: the processes that affect an organism’s remains between the time of death and burial.
• Diagenesis: the physical and chemical changes that occur during the conversion of sediment to rock and during the rock’s continued history.
• Fossilization: the process by which remains are preserved as fossils.
what is meant by “biocoenosis” and “thanatocoenosis”
”Biocoenosis” refers to the assemblage of living organisms in an ecological community at any one time. “Thanatocoenosis” refers to the assemblage of dead organismal remains that are found together.
What is “time averaging” in a fossil assemblage? How is it related to
sedimentation rates?
”Time averaging” in a fossil assemblage is the mixing of remains from different time periods into one layer, which can obscure the interpretation of the paleoenvironment. It’s related to sedimentation rates because slower rates tend to increase time averaging.
What are the most common substances/minerals that are preserved in
fossils?
Common minerals that preserve in fossils include calcite, silica, pyrite, and phosphate. These minerals can replace or fill in the spaces of original organic materials.
What impact does fluvial transport have on fossils, especially vertebrate
skeletons?
Fluvial transport can round bones, sort them by size, and abrade them, potentially separating parts of skeletons and leading to a biased fossil record.
What conditions favor fossil preservation, especially exceptional fossil
preservation with soft tissue traces?
Exceptional fossil preservation is favored by rapid burial, anoxic environments, and the presence of fine-grained sediment, which can preserve soft tissue traces.
What is a Lagerstätten?
A Lagerstätte is a sedimentary deposit that exhibits extraordinary fossil preservation, often including soft tissues.
What is meant by “autochthonous”, “parautochthonous”, and
“allochthonous”? What are ways that organism behavior, sedimentation
rates, erosion, and hydraulic energy can influence the formation of these
assemblages?
“Autochthonous” refers to organisms that are buried where they lived; “parautochthonous” refers to organisms that are displaced slightly from their living position; “allochthonous” refers to organisms that are carried far from where they lived. Organism behavior, sedimentation rates, erosion, and hydraulic energy influence the distribution and mixing of these assemblages.
What does a complex internal structure indicate about a fossil assemblage?
A complex internal structure in a fossil assemblage can indicate active biological processes, such as burrowing or predation, and it can also suggest the presence of a once diverse ecosystem.
Know what the common types of fossil preservation are:
a. Original soft parts
b. Compression, impression, and carbonization
c. Original hard part preservation
d. Recrystallization
e. Permineralization and replacement
f. Natural molds and casts
The common types of fossil preservation are:
a. Original soft parts: Preservation of actual organic material.
b. Compression, impression, and carbonization: Organisms are flattened, leaving a carbon imprint.
c. Original hard part preservation: Hard parts like bones and shells remain.
d. Recrystallization: Original minerals are replaced with different minerals.
e. Permineralization and replacement: Space in the organism’s remains is filled with minerals.
f. Natural molds and casts: Organisms leave impressions which are then filled with minerals.
Taphonomic processes influence paleoecology, biostratigraphy, and anatomy by altering the original context and condition of fossils, which can lead to misinterpretation of the ancient environment, timing, and biological structures.
What are influences that taphonomic processes have on the study of
paleoecology, biostratigraphy, and anatomy?
Taphonomic processes influence Paleoecology, biostratigraphy, and anatomy by altering the original context and condition of fossils which can lead to misinterpretation of ancient environmental timing and biological structures
