highly significantP < 0.01
4 ) that is also highly significant ( P < 0.01 , one-sided), but varies considerably from state to state ( SI Appendix , Fig.
4 ) that is also highly significant ( P < 0.01 , one-sided), but varies considerably from state to state ( SI Appendix , Fig.
Beyond shifts in the mean, a positive trend in δ Y t indicates that changes in the timing of crop development are more beneficial under recent climate and, thus, represent adaptation to changes in climate.