miners' canaries
Pit gas detectors
Miners' canaries are the small birds once kept in coal mines to detect poisonous gases.
Because canaries are more sensitive to carbon monoxide and methane than humans, their distress or death served as an early warning system, giving miners time to evacuate.
The practice has largely ended, but the phrase persists as a metaphor for any early indicator of danger: Honeybee populations are the miners' canaries of environmental health.
Below ground or countercultural
- shaftNarrow vertical passage
- tunnelEnclosed underground route
- ventilationCirculation of fresh air
- black lungCoal dust respiratory disease
anthracite · bituminous · pitman · seam · headgear · longwall · gallery · drift
Guard who monitors
- harbingerOne who foreshadows
- indicatorSign revealing status
- alarmUrgent warning signal
- foreshadowIndicate future events
omen · early warning · bellwether · signal · precursor · predictor · herald · forewarning
Trend-setting leader
- leading indicatorMetric forecasting future conditions
- test subjectExperiment participant
- sacrificeGiving up something precious
- scapegoatUnfairly blamed person
Ease of breaking
- sensitivityResponsiveness to stimuli
- exposureState of being unprotected
- susceptibilityLiability to influence
- defenselessnessState of being unprotected
delicacy · weakness · expendability · helplessness · innocence · small size · metabolism · caged
underground
Below ground or countercultural
- shaftNarrow vertical passage
- tunnelEnclosed underground route
- ventilationCirculation of fresh air
black lung · anthracite · bituminous · pitman · seam · headgear · longwall · gallery · drift · methane
sentinel
Guard who monitors
foreshadow · omen · early warning · bellwether · signal · precursor · predictor · herald · forewarning · portent
bellwether
Trend-setting leader
- leading indicatorMetric forecasting future conditions
- test subjectExperiment participant
- sacrificeGiving up something precious
fragility
Ease of breaking
- sensitivityResponsiveness to stimuli
- exposureState of being unprotected
- susceptibilityLiability to influence
defenselessness · delicacy · weakness · expendability · helplessness · innocence · small size · metabolism · caged · trapped