I was walking towards the banks of Kelambakkam back waters. This is a relatively remote part of the backwaters running along the village of Padur, just north of Kelambakkam. It was a grey morning with a slight drizzle, so I was holding an umbrella in one hand and my camera in the other. I had to park my car on a road that trailed off into a small path that ran along some abandoned fields. There were a lot of thorny bushes. The kind that are used as firewood. The ground was very swampy and all my attention was down to see where was putting my feet. I had hardly walked 50 metres when I was swept into a whirlwind of swallows.
They were zipping, dipping and diving around me. These were barn swallows judging by their low circular flying, brownish colour and forked tails. I had walked right into the middle of a barn swallow feeding event. They seemed to be picking off insects buzzing above the water. Occasionally they skimmed and dipped their beak in the water too. Some flew so close that I could hear their wings cutting through the air. Taking pictures was a challenge. I was too close, they were too small and they were flying too fast. Their brown colour merged with the ground and light conditions were poor on the grey day. With an open umbrella in one hand and my camera in the other, I tried to take a few pictures. I started feeling dizzy and disoriented from all the turning round and roundthat I had to do to follow them. When I stopped whirling like a dervish the world around me was still spinning. Feeling very wobbly and afraid to drop the camera I made it back to the car through the slush over the swampy ground.
I later read that these swallows can dive bomb people if they get too close to their nesting place. But there were no sheds or buildings where swallows normally build their nests. I also learnt that barn swallows sometimes end up clocking about 600 miles in feeding circles in a single day. These barn swallows evolved as a separate subspecies from the swallow species, along with human settlements around 7700 years ago. Before humans started settlements and building small sheds for their cattle, and storing their harvest, these sub species did not even exist. Their evolution began when swallows started nesting in these man-made sheds. Soon a sizable number started nesting and living around and off these sheds. These groups lived so close to these sheds that they broke off any contact with the other tree nesting swallows. Eventually they started breeding within themselves too. This event is known as a founder event in evolution — when a small number of individuals are able to succeed in a new environment which is unique and different from their original environment. Soon they became a unique different species from their main species group. And they were named as barn swallows.
There are animals like dogs for whom humans consciously and deliberately played a role in their evolution. And then there are these barn swallows where humans unconsciously played a role in their evolution.