The iconic Wimbledon tennis tournament kicks off today and over the following two weeks thousands of people will descend on a tiny corner of south west London to watch the greatest tennis players in the world.

One of the things that most of the people watching Wimbledon at home or in person are the bright yellow balls being hit between competitors.

While these balls have been a staple of tennis around the world for decades, very few people know why they are yellow or who came up with the idea.

The answer is that the reason why almost all tennis balls are bright yellow is because of one Sir David Attenborough.

In the late 1960s, the yet-to-be knighted Sir David was working at the BBC and his job as a controller was to bring colour to British televisions.

Whilst watching a tennis match, Sir David realised it was quite hard to see the ball. This was because at the time tennis balls were either black or white.

According to authors John Lloyd, James Harkin, and Anne Miller, in their book ‘2,2024 QI Facts To Stop You In Your Tracks’ it was Sir David who suggested that for the balls to stand out better on television, they should be yellow.

They wrote: “Yellow tennis balls, which look better on colour TV, were the idea of David Attenborough when he was Controller of BBC2.”

Sir David, now 98, has written about his role at the BBC in recent years. Speaking to the Radio Times in 2017 he talked about how it was his idea to bring colour television to Wimbledon.

He said: “And it suddenly dawned on me that the one thing we did have was outside broadcast units. I thought, “Blimey, couldn’t we deploy them?” And then I thought of Wimbledon.

“I mean, it is a wonderful plot: you’ve got drama, you’ve got everything. And it’s a national event, it’s got everything going for it. I was as proud as a peacock. It was absolutely terrific. It was a big moment in my life.”