Giant meteorites from outer space, fire storms, tidal waves and an ice age have all been suggested by experts to explain the demise of T-Rex and other giant dinosaurs.

However, the latest theory to explain their extinction claims they did not survive because their reptilian sleeping patterns meant their brains did not learn new skills properly.

Unlike mammals and birds, reptiles are unable to experience slow wave sleep, the type of sleep believed to be responsible for boosting memories, especially those connected to performing new tasks.

As a result, reptiles are much more limited in the type of complex behaviour they can experience than other animals such as mammals and birds.