Reconstructing our three hominins (human ancestors) proved a real challenge. We wanted to make life-size sculptures of three individuals, and to make them as realistic as possible, but when you’re trying to reconstruct someone from thousands of years ago, you have very little to go on! We based the reconstructions on fossil skeletons, but no fossil skeletons are complete, so the first challenge for the model makers from Crawley Creatures was to fill in the missing gaps. With the Neanderthal, we were lucky, because researchers had recently produced a composite Neanderthal skeleton, based primarily on a fossil called La Ferrassie 1, but using bones from other Neanderthal fossils to complete it. For our Homo erectus reconstruction, we chose Nariokotome Boy, a remarkably complete fossil skeleton, but we had to use a bit of artistic licence when it came to his feet - which are missing from the fossil. Our australopithecine is the famous Lucy, for which we have almost 40% of a skeleton, and we filled in the gaps with casts of other australopithecine bones. We used accurate casts of the original fossil bones, and I helped the model makers to assemble the skeletons into life-like poses. Then the fun started, as we added clay muscles to the bones. The heads were modelled by palaeo-artist Viktor Deak, and he came over from the States to assemble the heads onto the bodies. I didn’t see the reconstructions at that stage and I was rather worried that they would look Frankenstein-like! But I was really impressed by the finished sculptures - we reveal one at the end of each programme. George McGavin and I really hadn’t seen the final reconstructions until that moment of unveiling - so it was a genuine revelation. I think the reconstructions are great and I’m looking forward to seeing them again, in the flesh, in Birmingham, when the series goes out - they’ll be in Thinktank from Monday 22nd to Thursday 25th.