Tree rings from ancient bristlecone pines and from the wood of historical buildings provide overlapping records of climate extending back more than 9,000 years. Years of drought produce narrow rings; favorable years produce wider rings. Comparing ring patterns across multiple sites can distinguish local effects from widespread climate events. Researchers have used these records to correlate certain civilizational disruptions in ancient societies with multi-decade droughts.
Which inference is most strongly supported by the passage?
- A
Climate over the past 9,000 years has been uniform
- B
Tree rings record only events specific to a single tree's location
- Ccheck_circle
Tree-ring evidence suggests environmental variability has been a relevant factor in some historical episodes
- D
All civilizational change has environmental, rather than social, causes
Explanation
Correlations between droughts and civilizational disruptions supports A. B overstates causation; C contradicts cross-site comparison; D contradicts variability.