Date: November 25, 2015
Source: Cell Press
Many birds travel in flocks, sometimes migrating over thousands of miles. But how do the birds decide who will lead the way? Researchers reporting in the Cell Press journal Current Biology on November 25 now have some new insight based on studies in homing pigeons. For pigeons, it seems, leadership is largely a question of speed.
"This changes our understanding of how the flocks are structured and why flocks of this species have consistent leadership hierarchies," says Dora Biro of the University of Oxford.
Previous studies had shown that flock leadership is unrelated to social dominance. Giving followers extra training flights doesn't promote them to a position of leadership, either. The new findings offer an elegantly simple explanation for the phenomenon of leadership in birds, with important implications for how spatial knowledge is generated and retained in navigating flocks.
While many birds travel in flocks, homing pigeons are domestic and more easily studied than most. "We can control the composition of the flocks and the starting points for their homeward journeys," says Benjamin Pettit, the first author of the new study. "We also have a good understanding of their individual spatial cognition, in particular how their homing routes develop over repeated flights in the same area."
Recent developments in sensor technology also make it possible to explore with exquisite precision how pigeon flocks are coordinated. The latest GPS loggers allow the researchers to track not only the birds' overall routes, but also the sub-second time delays with which they react to each other while flying as a flock.