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Mrs. Reno EH Vocab
Earth History Vocabulary
Question | Answer |
---|---|
Theory | In science, an explanation for natural events that is based on a large number of observations and is in accord with existing scientific principles. |
Uniformitarianism | The hypothesis that the Earth developed gradually through natural processes still at work today. Examples: weathering processes, erosion, volcanoes, earthquakes, etc...) |
Stratigraphy | A branch of geology, studying rock layers and layering. |
Extinction | The death of all members of a species. |
Fossil | The remains of an organism or sign of an organism, usually preserved in rock. |
Plate Tectonics | Theory of geology that the Earth's lithosphere is broken up into large plates which move over time. |
Paleontology | The study of prehistoric life forms on Earth through the examination of plant and animal fossils. |
Geologic Time Scale | Used by geologists and other scientists to describe the timing and relationships between events that have occurred during the history of the Earth. |
Radiometric Dating | A technique to date materials, based on the comparison between the observed amount of a naturaly occurring radioactive isotope (uranium) and their known decay rates. |
Fitness | The reproductive success of an organism |
Adaptations | Characteristics/variations of an organism that helps it survive in a particular environment |
Natual Selection | The unequal survival and reproduction of organisms due to the preservation of favorable adaptations. |
Population | A group of individuals of the same species, found in the same time and place and are able to reproduce |
Evolution | A change in genetic traits of a species that distinguishes it from previous populations as a new species of animal. Permanent genetic adaptations. |
Species | A group of organisms that share similar characteristics and can reproduce among themselves to produce fertile offspring. |
Variation | An inherited trait that makes an individual different from other members of its species. Results from mutations in the genes of the organism (permanent) |
Gradualism | A slow, ongoing process where one species changes into a new species. |
Punctuated Equilibrium | A rapid process where the mutation of a few genes results in the appearance of a new species over a relatively short period of time. |
Sedimentary Rock | Formed when layers of sand, silt, clay, or mud are compacted and cemented together. examples: limestone, sandstone, shale |
Radioactive Element (Isotope) | An element that gives off a steady amount of radiation as it slowly changes to a nonradioactive element |
Embryology | The study of embryos and their development. |
Homologous | Body parts that are similar in origin and structure. |
Vestigal Structures. | Structures that no longer seem to have a function. |
Relative Dating | A way to find the approximate age of the Earth and Fossils using the position of in the rock layers. |
Absolute Dating | The exact age of an object (such as a rock or artifact); found by techniques, such as the study of growth rings in trees and radiocarbon dating. |
Law of Superposition | A law that states that the oldest rock layer Is at the bottom and each layer above is the youngest. |
Precambrian Eon | Earth's formation which accounts for 85% of Earth's history. No fossil Record |
Paleozoic Era | An era of Earth's history where several plant and animal species evolve. Accounts for 8.5% of Earth's history. Occurs after the Precambrian Era and before the Mesozoic Era |
Mesozoic Era | An era of Earth's history where several dinosaurs adn birds evolve. Accounts for 3.5% of Earth's history. |
Cenozioc Era | An era of Earth's history where mammals evolve. Accounts for 1.4% of Earth's history. |
Eon | Represents a large part of geologic time and the longest unit of time. |
Epoch | An interval of geologic time that is longer than an age and shorter than a period. |
Era | A broad span of geological time based on the general type of life existing during the time. The four eras on Earth are Precambrian, Paleozoic, Mesozoic, and Cenozoic. |
Period | A unit of geologic time that is longer than an Epoch and shorter than an Era. Examples: Proterozoic, Archean, Cambrian, Ordovician, Silurian, Devonian, Carboniferous, Permian, Triassic, Jurassic, Cretaceous, Tertiary, Quaternary |
Age | Represents a small part of geologic time and is the shortest unit of time. |
Half Life | The number of years needed for half of an isotope to decay. Example: 50%, 25%, 12.5%, 6.25%, 3.125% |
"Meso" | middle |
"Paleo" | ancient life |
"Ceno" | recent life |
"Homo" | The same |
Cast | Secondary mold that is a replica of the original. |
Endangered | Threatened with danger or extinction. |
Trace fossil | A fossilized track, burrow, or other sign of activity of life of an animal made in sedimentary rock. |
Carbon Film | A type of preservation or fossilation that happens as a result of pressure and heat from being buried. What remains is a thin film of the remaining carbon from inside the organisms body, showing a silhouette of the original body. |
Mold | An impression made in the Earth by an organism as it is fossilized. |
Petrified Fossil | The fossilization of an organism from the Conversion of organic material into inorganic material. |
Amber | A yellow, brown, or transluscent resin that comes from Coniferous Trees (pine trees). |
Tar | A molasses-like liquid petroleum product that oozes from the Earth's surface. |
Pseudofossil | A natural occuring object that looks like a fossil, but is not. |
Preserved | To keep in perfect or unaltered, original condition |
Horizontal | Parallel to the ground. Example: Lying flat on your back. |
"Pseudo" | False |
"Uni" | One or "One in the Same" |
Geology | Study of Earth's processes |
"Geo" | Earth |
"ology" | The study of |
"strata" | Layers |
"graphy" | illustration or drawings of |
"ologist" | A person who studies |
Geologist | A person who studies Earth's processes. |
Invertebrates | Organisms that are lacking a vertebrate or "backbone" |
Vertebrates | Organisms that have a vertebrate or "backbone" |
Cladogram | A branching diagram that shows the progressive evolution of species with a common ancestor. |
Biodiversity | diversity amoung plants and animals species within an environment. |