I was studying large flocks of birds through out our summer. By flocks I mean groupings of birds with a population of more than several hundred. Large flocks that spread out over a large amount of airspace flying as they do together in what appears to be random spirals, and irregular flight paths. case in question: The total distance from the edges of the flock across it's center would have been approxinmately 100 meters. all birds appeared to be changing direction simultaneously. I wondered how they could do this so incredibly in synch. [ chance....fluke except this is repeated all through out their flight many times] One suggestion offered by many a sceptic is that their smoothness of change in direction is purely reflexive based on ordinary sensory data. My rebuttal: this can not be so as the birds on the edge have their view completely blocked by birds between them and the other edge. One would expect to see a very fast butterfly effect as one bird led and the others very quickly followed however no such effect is witnessed and no lead bird can be discerned. They do appear for all intents and purposes to be flying as a single unit with over 600 individual aspects and perspectives moving as one entiy [ a little flexibility but essentially one entity ] So how can all birds alter their flight path exactly at the same time with out some sort of communication allowing them to do so and by virtue of their incredible movement in unison that communication must be instantaneous. I know reflexes can be very fast but spread over such a distance and with so many birds involved this is extremely unlikely as a solution. Simlar can be found with large groupings of fish such as sardine and white bait... [ even in murky water ] The solution can only be telepathic or empathic communication....what say you? ps I intend to video the birds in question and then discect the video down to frames [1/25 of a minute I think] and show that the change in flight path is instantaneous or at least so close that it may as well be.