0:00:02 > 0:00:04BELL RINGS Ooh, a treasure chest!
0:00:04 > 0:00:07That looks very mysterious, Colin.
0:00:07 > 0:00:10It belonged to my great, great, great-granduncle Percy.
0:00:10 > 0:00:13It's been in our family for years.
0:00:13 > 0:00:15- PROFESSOR MCCORK:- Ah, he must've been a pirate.
0:00:15 > 0:00:20Ooh, how exciting! Imagine life as a pirate, Jonathan.
0:00:20 > 0:00:22You could have your own parrot and an eye patch and...
0:00:22 > 0:00:25and you could make me walk the plank if I'm late for work.
0:00:25 > 0:00:29It would be quite a step up from floor manager.
0:00:29 > 0:00:32- Arrr! Shiver me timbers!- Uh!
0:00:32 > 0:00:34- BELL RINGS - Positions, everyone!
0:00:34 > 0:00:37'This is Brain Freeze.
0:00:37 > 0:00:40'With Dr Knowles,
0:00:40 > 0:00:43'Professor McCork,
0:00:43 > 0:00:46'Colin, the floor manager
0:00:46 > 0:00:48'and Ms Hucklebuck.
0:00:48 > 0:00:50'STAND BY!'
0:00:50 > 0:00:51Come on, everybody!
0:00:54 > 0:00:56- BOTH:- It's time for...
0:00:59 > 0:01:00Today we're asking,
0:01:00 > 0:01:02is everyone related?
0:01:02 > 0:01:03To try and answer this,
0:01:03 > 0:01:06let's start at the present day and work backwards.
0:01:06 > 0:01:08If we assume that every person
0:01:08 > 0:01:10has two biological parents,
0:01:10 > 0:01:11four grandparents,
0:01:11 > 0:01:13eight great-grandparents and so on,
0:01:13 > 0:01:15the numbers continue to double
0:01:15 > 0:01:17with each generation we go back
0:01:17 > 0:01:20and soon become very large.
0:01:20 > 0:01:22By the time we've gone back about 2,000 years,
0:01:22 > 0:01:24our family tree would consist of
0:01:24 > 0:01:27one quintillion separate individuals.
0:01:27 > 0:01:29One quintillion?
0:01:29 > 0:01:32But that's more than the number of people that have ever lived.
0:01:32 > 0:01:36Exactly! It seems that we simply have too many ancestors.
0:01:36 > 0:01:39- So what's going on? - Join us after the break to find out.
0:01:39 > 0:01:41And we're clear!
0:01:41 > 0:01:43I can picture it now.
0:01:43 > 0:01:47Captain Jonathan, just like Percy the Pirate.
0:01:47 > 0:01:50Swashbuckling on the high seas. Arrr!
0:01:50 > 0:01:54Discovering buried treasure. Arrr!
0:01:54 > 0:01:56Flying big aeroplanes all around the world.
0:01:56 > 0:02:00- Uh, I think that's a pilot you're thinking of, Professor.- Oh, yeah.
0:02:00 > 0:02:02Well, I would like to honour Percy's memory,
0:02:02 > 0:02:06but all this pirate stuff sounds terribly dangerous.
0:02:06 > 0:02:09Nonsense! Let's get you in shipshape.
0:02:09 > 0:02:11But I can't read a compass.
0:02:11 > 0:02:13I'm allergic to seafood!
0:02:13 > 0:02:15BELL RINGS
0:02:15 > 0:02:17Hm. Something's not right here.
0:02:23 > 0:02:24So, tell us, Dr Knowles,
0:02:24 > 0:02:27what's the story with the one quintillion ancestors?
0:02:27 > 0:02:31The problem of having too many ancestors can be explained by
0:02:31 > 0:02:35the fact that many of these are in fact the same person occupying
0:02:35 > 0:02:37multiple places on the family tree.
0:02:37 > 0:02:39Over many generations,
0:02:39 > 0:02:40descendants of these individuals
0:02:40 > 0:02:42actually ended up having children together,
0:02:42 > 0:02:45even though they were in fact distant relatives.
0:02:45 > 0:02:48So, is everyone related then?
0:02:48 > 0:02:51Well, yes. Even you and me.
0:02:53 > 0:02:56Some scientists believe that every single person on earth
0:02:56 > 0:02:59is at least 50th cousins with everybody else.
0:02:59 > 0:03:01And if you live in the same country
0:03:01 > 0:03:03and are of the same ethnicity as someone,
0:03:03 > 0:03:05chances are it's even closer.
0:03:05 > 0:03:08Phew! I think I need a rest after all this.
0:03:08 > 0:03:10See you next time, folks!
0:03:11 > 0:03:13And we're clear...oh.
0:03:13 > 0:03:16Hey, guys, I think there's something you need to know
0:03:16 > 0:03:19- about Percy the Pirate.- Huh?
0:03:19 > 0:03:22Look, he was an astronaut as well.
0:03:22 > 0:03:24And a gladiator.
0:03:24 > 0:03:26And a giant chicken.
0:03:26 > 0:03:28No, he wasn't any of these things.
0:03:28 > 0:03:33Percy worked as a floor manager at a costume and fancy dress shop!
0:03:33 > 0:03:37Ah-ha! A floor manager, just like me.
0:03:37 > 0:03:40The apple doesn't fall far from the tree.
0:03:40 > 0:03:44Well, I guess you can follow in Percy's footsteps after all, Colin -
0:03:44 > 0:03:47by staying right where you aRRR!
0:03:47 > 0:03:48Arrr!
0:03:48 > 0:03:50THEY LAUGH
0:04:02 > 0:04:03Brain Freeze.