The science siblings are still on their Christmas break, and so this week, rather than wading through the GCSE science curriculum they are instead trying to work out what evolutionary pressures a small reindeer population would need in order to become airborne.

First, Ron talks Laura through the basics of evolution and how it all works. Then, they get to work in designing an island on which, given a few millenia, reindeer might slowly become flying creatures. Sit back, enjoy and try not to take it too seriously.

Merry Christmas everyone!

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