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80 terms

Evolution of Landforms and Lifeforms

Index Fossils
Fossils known to have lived in a particular geologic age that can be used to determine the date of the rock layer in which it was found.
A fracture along which the blocks of Earth's crust on either side have moved relative to one another.
Metamorphic Rock
Rock created from the transformation of other types of rock through heat and pressure.
An inherited mutation in an organism's DNA that provided an advantage for survival of a species.
The set of alleles that determines the expression of a particular characteristic of trait.
The study of rocks, processes, and history of Earth.
The number and variety of species present in an area.
Absolute Dating
Using the known rates of decay of radioactive materials to determine the age of an object.
Relative Dating
A method used to approximate the age of rock using the order of layers in the ground.
Geographic Changes
Changes that have occurred on Earth throughout many years.
Law of Superposition
A basic law of geology, stating that in any undisturbed sequence of rocks deposited in layers the top is the youngest.
Ice Cores
A sample that is typically removed from an ice sheet most commonly from the polar ice caps and contain an abundance of information about climate.
The remains of a prehistoric organism or geologic artifact as a mold or cast in rock.
Geologic Time Scale
A record of the geologic events and life forms in Earth's history.
The chemical element of atomic number 92. A gray, dense radioactive metal used as a fuel in nuclear reactors.
Plate Tectonics
Pieces of Earth's crust and uppermost mantle, together referred to as the lithosphere.
Sedimentary Rock
The type of rock that is made of Earth's materials deposited by erosion.
Genetic Variation
Differences between members of species or between groups of different species.
Theory of Evolution
The theory that organisms change over time.
The complete elimination of a species.
Embryological Similarities
Similarities in the embryonic stage of development between different species.
Comparative Anatomy
The analysis of body structures between two or more species.
Biological Classification
The organization and identification of an organism from general to specific.
New organism produced by one or more parents.
The physical appearance of an organism.
Analogous Structures
Structures that have similar features and have evolved, but have different origins.
Homologous Structures
An organ or bone that appears in different animals, but has the same function and comes from the same origin.
Igneous Rock
A rock formed from the cooling and solidification of magma or lava.
The largest time unit on the geological time scale.
A scientist who studies fossils and the history of life on Earth.
A basic unit of the geologic time scale that is a subdivision of an era.
The gaseous portion of a planet.
All geologic time prior to the Phanerozoic eon.
Dome-like structures formed when sticky organic filaments of bacteria and algae trap mud.
Proposed super continent which 200 million years ago began to break apart and formed the present landmasses.
Phanerozoic Eon
The part of geologic time represented by rocks containing abundant fossil evidence.
Covered with or affected by a glacier.
A major division on the geologic time scale that is a subdivision of an eon.
Preserved traces
Footprints, burrows, or even wastes
The process by which remains or traces of living things become fossils
Sedimentary rock
Most fossils are preserved in _____
Tar, Ice, Tree sap/Amber
Things that may preserve organisms
imprint of an organism left in rock
fossil that formed when an organism is pressed into clay or soft earth
Trees can become petrified when the pores, or holes inside become filled with __________-
time it takes for half of a given amount of an isotoop to decay
Atoms of an element with different number of neutrons but the same number of protons
Carbon-14 dating
The best-known method of radiometric dating
Radioactive decay
the breakdown of unstable elements into stable elements
Absolute age
The age of a rock in years, determined by radiometric methods
the study of rock strata
position of rock layers and their relative ages
gap in the sequence of rock layers
Paleozoic Era and the Mesozoic Era
Two Largest mass extinction known
Organisms with external skeletons
Phanerozoic Eon
period of geological history that spans 542 million years and is typically subdivided into three eras. These eras are: Paleozoic Era: 542 to 251 million years ago. Mesozoic Era: 251 to 65 million years ago. Cenozoic Era: 65 million years ago to present.
Mesozoic Era
"Middle Life" Era, life diversified rapidly and giant reptiles, dinosaurs and other monstrous beasts roamed the Earth.
Cambrian Period
first geological time period of the Paleozoic Era (the "time of ancient life"). This period lasted about 53 million years and marked a dramatic burst of evolutionary changes in life on Earth, known as the "Cambrian Explosion."
Cenozoic Era
also known as the Age of Mammals because the extinction of many groups of giant mammals, allowing smaller species to thrive and diversify because their predators no longer existed
Paleozoic Era
The era began with the breakup of one supercontinent and the formation of another. Plants became widespread. Invertebres and fish were the most common. And the first vertebrate animals colonized land.
Some of the characteristics an organism has may help it survive
Process of many adaptations throughout history, descendants becoming very different from their ancestors
A random change in an organisms genes
Phanerozoic eon, Cenozoic era, Quarternary period, and teh holocene epoch
What we currently live in, (all)
Precambrian major events
Earth Began, Bacteria appear
Paleozoic major events
Coral reefs develop, Trilobites appear, and the Age of fish begins
Mesozoic major events
Dinosaurs appear, and Dinosaurs become extinct
Cenozoic major events
Mammals, flowering plants, and insects dominate the land
Convergent Evolution
process whereby organisms not closely related, independently evolve similar traits as a result of having to adapt to similar environments
Vestigial Structure
Something that no longer does what it was evolved for
When organisms change in small ways over time
Much bigger evolutionary changes that result in new species.
Natural Selection
inherited traits of a population change over time. the process whereby organisms better adapted to their environment tend to survive and produce more offspring.
Inherited traits
features that are passed from one generation to the next
Acquired traits
traits the organisms devolp over a lifetime
This person believed that characteristics such as muscle/body mass could be passed down
Hydro thermal vents
A fissure on the floor of a sea out of which flows water that has been heated by underlying magma
Geologic time scale
time line dividing the earth's history into units representing millions of years
Dome-like structures formed when sticky organic filaments of bacteria and algae trap mud
Ice core
Cylinder-shaped sample of ice drilled from a glacier, it is a great way to investigate past climate and atmospheric conditions