Definition of facultative in English:

facultative

adjective ˈfak(ə)lˌtətɪvˈfækəlˌteɪdɪv

1Occurring optionally in response to circumstances rather than by nature.
偶发的
facultative adjustment in relation to competitive abilities
Example sentencesExamples
- Although the sample is small, this is a powerful test of the facultative response of females to changes in the composition of their group.
- Snakes of both groups ate readily, showing that reproduction-associated anorexia was a facultative response to lack of prey in the den.
- To date, no physiological mechanism for facultative sex ratio adjustment in birds has been identified.
- This paucity of experimental data makes it difficult to identify the ecological conditions that favor the evolution of the facultative response and of the particular environmental cues that may trigger it.
- These responses can and often are superimposed upon more programmed life history traits in ways that can suggest specific mechanisms by which facultative responses can become obligate.
1. 1.1Biology Capable of but not restricted to a particular function or mode of life.
  〔生〕兼性的
  a facultative parasite
  兼性寄生物。常与OBLIGATE 相对。
  Often contrasted with obligate
  Example sentencesExamples
  Hughes argued that egg mimicry provides additional evidence that Black - billed and Yellow-billed cuckoos were obligate brood parasites in the past because such mimicry is unlikely to evolve in a facultative brood parasite.
  The filamentous fungus Fusarium oxysporum is a soil-borne facultative parasite that causes economically important losses in a wide variety of crops.
  Other parasites will feed on any host available and are called facultative parasites.
  The functional significance of facultative sibling aggression is likely to depend on the magnitude of competitive asymmetry between siblings.
  Many species of Chlamydomonas are facultative auxotrophs, capable of utilizing acetate as their sole carbon and energy source.

Derivatives

facultatively

adverb

Among bats, larger species among the Pteropodidae (Old World fruit bats with mass in the range 0.21.5 kg) often glide or soar, and use undulating flight facultatively.
Example sentencesExamples
- Insects such as ants, wasps and flies from the vicinity are attracted to these rewards and defend the plants facultatively against herbivores.
- The adult cowtail stingray of Shark Bay, Western Australia, is a solitarily foraging animal that facultatively groups when resting on shallow, inshore sand flats.
- In many, if not all, facultatively social bees, ecological factors such as competition for nesting sites and predation seem to promote social nesting, although genetic differences may also underlie social variation.
- The heterogeneous enrichment among individual worms agrees with reports that this nominal deposit feeder can facultatively filter-feed using a mucus net in its burrow, and that the ability to do so varies among populations.

Origin

Early 19th century: from French facultatif, -ive, from faculté (see faculty).

Definition of facultative in US English:

facultative

adjectiveˈfækəlˌteɪdɪvˈfakəlˌtādiv

1Occurring optionally in response to circumstances rather than by nature.
偶发的
the difference between facultative skin pigmentation and constitutive pigmentation is a function of overall sun exposure
Example sentencesExamples
- Snakes of both groups ate readily, showing that reproduction-associated anorexia was a facultative response to lack of prey in the den.
- To date, no physiological mechanism for facultative sex ratio adjustment in birds has been identified.
- This paucity of experimental data makes it difficult to identify the ecological conditions that favor the evolution of the facultative response and of the particular environmental cues that may trigger it.
- Although the sample is small, this is a powerful test of the facultative response of females to changes in the composition of their group.
- These responses can and often are superimposed upon more programmed life history traits in ways that can suggest specific mechanisms by which facultative responses can become obligate.
1. 1.1Biology Capable of but not restricted to a particular function or mode of life.
  〔生〕兼性的
  a facultative parasite
  兼性寄生物。常与OBLIGATE 相对。
  Often contrasted with obligate
  Example sentencesExamples
  Other parasites will feed on any host available and are called facultative parasites.
  Many species of Chlamydomonas are facultative auxotrophs, capable of utilizing acetate as their sole carbon and energy source.
  The functional significance of facultative sibling aggression is likely to depend on the magnitude of competitive asymmetry between siblings.
  The filamentous fungus Fusarium oxysporum is a soil-borne facultative parasite that causes economically important losses in a wide variety of crops.
  Hughes argued that egg mimicry provides additional evidence that Black - billed and Yellow-billed cuckoos were obligate brood parasites in the past because such mimicry is unlikely to evolve in a facultative brood parasite.

Origin

Early 19th century: from French facultatif, -ive, from faculté (see faculty).

单词	facultative
释义	Definition of facultative in English: facultative adjective ˈfak(ə)lˌtətɪvˈfækəlˌteɪdɪv 1Occurring optionally in response to circumstances rather than by nature. 偶发的 facultative adjustment in relation to competitive abilities Example sentencesExamples Although the sample is small, this is a powerful test of the facultative response of females to changes in the composition of their group. Snakes of both groups ate readily, showing that reproduction-associated anorexia was a facultative response to lack of prey in the den. To date, no physiological mechanism for facultative sex ratio adjustment in birds has been identified. This paucity of experimental data makes it difficult to identify the ecological conditions that favor the evolution of the facultative response and of the particular environmental cues that may trigger it. These responses can and often are superimposed upon more programmed life history traits in ways that can suggest specific mechanisms by which facultative responses can become obligate. 1.1Biology Capable of but not restricted to a particular function or mode of life. 〔生〕兼性的 a facultative parasite 兼性寄生物。常与OBLIGATE 相对。 Often contrasted with obligate Example sentencesExamples Hughes argued that egg mimicry provides additional evidence that Black - billed and Yellow-billed cuckoos were obligate brood parasites in the past because such mimicry is unlikely to evolve in a facultative brood parasite. The filamentous fungus Fusarium oxysporum is a soil-borne facultative parasite that causes economically important losses in a wide variety of crops. Other parasites will feed on any host available and are called facultative parasites. The functional significance of facultative sibling aggression is likely to depend on the magnitude of competitive asymmetry between siblings. Many species of Chlamydomonas are facultative auxotrophs, capable of utilizing acetate as their sole carbon and energy source. Derivatives facultatively adverb Among bats, larger species among the Pteropodidae (Old World fruit bats with mass in the range 0.21.5 kg) often glide or soar, and use undulating flight facultatively. Example sentencesExamples Insects such as ants, wasps and flies from the vicinity are attracted to these rewards and defend the plants facultatively against herbivores. The adult cowtail stingray of Shark Bay, Western Australia, is a solitarily foraging animal that facultatively groups when resting on shallow, inshore sand flats. In many, if not all, facultatively social bees, ecological factors such as competition for nesting sites and predation seem to promote social nesting, although genetic differences may also underlie social variation. The heterogeneous enrichment among individual worms agrees with reports that this nominal deposit feeder can facultatively filter-feed using a mucus net in its burrow, and that the ability to do so varies among populations. Origin Early 19th century: from French facultatif, -ive, from faculté (see faculty). Definition of facultative in US English: facultative adjectiveˈfækəlˌteɪdɪvˈfakəlˌtādiv 1Occurring optionally in response to circumstances rather than by nature. 偶发的 the difference between facultative skin pigmentation and constitutive pigmentation is a function of overall sun exposure Example sentencesExamples Snakes of both groups ate readily, showing that reproduction-associated anorexia was a facultative response to lack of prey in the den. To date, no physiological mechanism for facultative sex ratio adjustment in birds has been identified. This paucity of experimental data makes it difficult to identify the ecological conditions that favor the evolution of the facultative response and of the particular environmental cues that may trigger it. Although the sample is small, this is a powerful test of the facultative response of females to changes in the composition of their group. These responses can and often are superimposed upon more programmed life history traits in ways that can suggest specific mechanisms by which facultative responses can become obligate. 1.1Biology Capable of but not restricted to a particular function or mode of life. 〔生〕兼性的 a facultative parasite 兼性寄生物。常与OBLIGATE 相对。 Often contrasted with obligate Example sentencesExamples Other parasites will feed on any host available and are called facultative parasites. Many species of Chlamydomonas are facultative auxotrophs, capable of utilizing acetate as their sole carbon and energy source. The functional significance of facultative sibling aggression is likely to depend on the magnitude of competitive asymmetry between siblings. The filamentous fungus Fusarium oxysporum is a soil-borne facultative parasite that causes economically important losses in a wide variety of crops. Hughes argued that egg mimicry provides additional evidence that Black - billed and Yellow-billed cuckoos were obligate brood parasites in the past because such mimicry is unlikely to evolve in a facultative brood parasite. Origin Early 19th century: from French facultatif, -ive, from faculté (see faculty).
随便看	holding ground holding of holding off holding operation holding paddock holding pattern holdings holding(s) holdings holding tank holding the reins holding up hold in higher regard hold in (high) esteem hold in high esteem hold in (high) regard hold in high regard hold in one's arms hold in regard/esteem hold in the palm of one's hand hold it hold it hold/keep at bay hold/keep down hold/keep in check