Breeding at higher latitude as measured by stable isotope is associated with higher photoperiod threshold and delayed reproductive development in a songbird
D. Singh, S. R. Reed, A. A. Kimmitt, K. A. Alford, E. D. Ketterson
The paper compares two bird populations to assess how photoperiod affects breeding latitude and reproductive timing, finding differences in critical photoperiod thresholds and migration distance.
bioRxiv · Oct 2, 2019 · PreprintEcology