An artists rendition of the murmuration. The swirling flights of starlings in Spain.
Researchers found that starlings sought to match the direction and speed of the nearest seven or so neighbours, rather than responding to the movements of all of the nearby birds around them.
A theory is that they do this to share information on the optimal food sources. the “information centre hypothesis”, suggests that when food is patchy and hard to find the best long-term solution requires mutual sharing of information among large numbers of individuals. Just as honeybees share the location of flower patches, birds that find food one day and share information overnight will benefit from similar information another day
This is very similar to the way that investors speculate!