Marcus has silenced Freddie with his knowledge of insects.

The bearded carpenter left the outspoken Oxford graduate speechless when he discovered a group of unusual bugs living in their outside swimming pool.

After diving into the water, Marcus queried: "Where'd they all come from?

"These little swimming b******s. They're not flies, they're proper pond things."

Fascinated by Marcus' discovery, Freddie - aka Halfwit - came over to inspect the water.

Freddie, 24, said: "They're quite cool because they are flies - they can fly and they can swim and they can go on the surface of the water. Pretty versatile."

However, the 35 year old quickly announced he knew what gave the strange bugs their unusual characteristics.

Marcus said: "There's f***ing millions of them in here! They're probably vestigial wings.

"You know, like where pervious special had them and as they've evolved they don't really work. Like the coccyx is a vestigial tail. It doesn't really do anything, but it used to be a tail. You know, your tailbone?"

Ignoring his housemate's intelligent remark, Halfwit sat in silence looking irritated and acted as though he had not heard Marcus's question.