Gnats, like many other creatures, gather together in large numbers for safety. A gnat which is part of a crowd is much less likely to become a tasty treat for a passing bird than one which is on its own.

However, these tiny flying insects are surprisingly choosy about their companions, preferring to stay close to members of their own family group. A study of mosquitoes (a close relation) by researchers at the University of Oslo showed that each group have a specific colouring to their eyes and this is how they recognise their relatives.

To prove this theory the researchers bred a large family of mosquitoes and observed how they all flew together. Then half of the group were fitted with tiny goggles which distorted the way they perceived colours. When released, the insects split into two distinct groups, one with goggles and one without.

Gnats tend to come out in the evening when it is cooler. At this time of day the setting sun casts a light nearer the red end of the spectrum. The gnat's simple optics are less effective in these conditions and they are attracted to any eye which has a colour close to their own. The unfortunate  result is that if your own eyes fit the bill, they will see you as a big brother or sister and stay close by your head.

Gnat Facts

• Gnats fly in circles because their right and left wings are different sizes.
• Carried by rising columns of warm air, gnats can reach altitudes of 5,000 meters. They are often to be found plastered to the leading edges of aircraft.
• A gnat with no wings looks a lot like an ant (unless it's a flying ant, which looks a lot like a gnat).
• The word 'gnat' spelt backwards is 'tang'. By coincidence this is pretty much the last sound a gnat hears as it hits a car number plate.