evolutionary trend
Học thuậtThân thiện
An evolutionary trend shows species gradually developing longer necks over time.
Definition
Noun: A general, consistent, or prevailing direction of change observed in the characteristics of a lineage of organisms over the course of evolutionary time. It describes a pattern of phenotypic or genetic transformation across many generations.
Usage
The term "evolutionary trend" is used in biology and paleontology to describe and analyze long-term patterns in the fossil record or in genetic data. It indicates a directional shift, not a random fluctuation.
Examples
- The increase in brain size in the hominin lineage is a well-documented evolutionary trend.
- Scientists studied the evolutionary trend towards reduced body size in island-dwelling mammals.
- The fossil record shows an evolutionary trend from fins to limbs in early tetrapods.
Advanced Usage
- In a sentence: "The evolutionary trend towards floral symmetry in that plant family suggests a strong selective pressure from a specific pollinator."
- In academic discussion: "While a trend may be observed, it is important to distinguish a true evolutionary trend from a simple anagenetic change within a single lineage."
Variants and Related Words
- Trend (n): A general direction in which something is developing or changing. (More general, not specific to biology).
- Evolutionary pattern (n): A broader term that can include trends, stasis, or cyclical changes.
- Anagenesis (n): Evolutionary change within a single lineage, which can contribute to an observed trend.
Synonyms
- Directional evolution
- Phyletic trend
- Evolutionary trajectory (though "trajectory" can imply a more specific path)
Antonyms
- Evolutionary stasis (lack of directional change)
- Random fluctuation
Related Phrases and Concepts
- "To observe an evolutionary trend": To identify and document such a pattern from data.
- Researchers observed an evolutionary trend towards darker coloration in industrial areas.
- "To reverse an evolutionary trend": When a previously established direction of change is countered by a new selective pressure.
- The loss of predators may reverse the evolutionary trend towards defensive armor in some prey species.
An evolutionary trend shows species gradually developing longer necks over time.
Noun
- a general direction of evolutionary change