Readers discuss ancient plagues and a fern’s leaf revival

Under the weather

New climate reconstructions show that periods of decreasing temperature and rainfall coincided with three plagues that struck the Roman Empire, Bruce Bower reported in “Did climate drive ancient plagues?” (SN: 2/24/24, p. 13).

Bower reported that researchers are uncertain exactly how those climate shifts may have influenced the plagues’ spread. Reader Robert J. MacCoun asked if one explanation could be that the colder conditions drove people to spend more time indoors with poor ventilation.