There is a gecko in my office claims to be descended from a T-rex. The sad little lizard has nothing else to feel good about himself with, so I haven't told him that the actual descendants of the dinosaurs are modern-day birds.
As for David Cameron being a descendant of the twelve tribes of Hebrews that followed Moses out of Egypt, the
latest archaeological evidence is that the exodus actually happened to the Hyksos, and the Hebrews simply stole the story.
As for Moses, I tend to agree with Sigmund Freud that the
historical figure of Moses was actually an Egyptian, possibly even the 'heretic' monotheistic Pharaoh Akhenaten.