punctuated equilibrium
Noun: A theory in evolutionary biology proposing that species experience long periods of little or no morphological change (stasis), which are "punctuated" by relatively brief periods of rapid evolutionary change, often associated with speciation events. This pattern contrasts with the model of gradualism, which suggests evolution occurs as a steady, continuous process.
This term is used primarily in scientific contexts, specifically within evolutionary biology and paleontology, to describe a specific pattern observed in the fossil record and a theoretical model to explain it.
Examples: * The fossil evidence for this species supports the model of punctuated equilibrium, showing sudden appearance and long-term stability. * The concept of punctuated equilibrium was developed to explain why transitional fossils between species are often rare. * Debates between proponents of gradualism and punctuated equilibrium have shaped modern evolutionary thought.
- "Punctuated equilibrium model": The full name of the theory, often used for clarity.
- The punctuated equilibrium model challenges the traditional Darwinian view of constant, gradual change.
- The verb form "punctuate" is conceptually central but used separately. The theory describes how equilibrium is by change.
- Long periods of stasis are punctuated by episodes of rapid speciation.
- Punctuationalism (n): Another term for the theory of punctuated equilibrium, emphasizing the "punctuational" nature of change.
- Stasis (n): A state of stability or lack of change, a core component of the punctuated equilibrium model.
- Gradualism (n): The contrasting theory that evolutionary change occurs slowly and continuously over long periods.
- Punctuationalism (n)
- Punctuated equilibria (n, plural form)
- Gradualism (n)
- Phyletic gradualism (n)
- Speciation Event: The rapid evolutionary change in punctuated equilibrium is typically linked to a speciation event, where a new species branches off.
- Fossil Record: The primary source of evidence for this pattern, characterized by the sudden appearance of new species forms.
- Evolutionary Stasis: The prolonged period of little change that forms the "equilibrium" part of the theory.
-
a theory of evolution holding that evolutionary change in the fossil record came in fits and starts rather than in a steady process of slow change
Khám phá thêm
Các từ liên quan
Từ đồng nghĩa
Từ chứa "punctuated equilibrium"