OK so it's February - about time to discuss the Doctor Who Christmas Special eh!!
One more species turned up in the special, which unless you've been living in a cave for, well all your life you will know is heavily based on The Lion, The Witch and the Wardrobe. As ever a new species turned up in the special, so let's talk about it.
I thought these trees were quite cool and the concept was fun, the Doctor wants to take the kids to a planet with naturally occuring Christmas trees. Only the trees are a live and trying to escape before being burned alive for conversion into fuel. The whole 'life force' thing has always been a vague get-out not only in Doctor Who but in other sci-Fi too (would it hurt to say soul?!!) and the concept of the life force escaping into Madge and then...something wasn't the best, but the human trees were cool and the episode was good fun.
Androzani trees are a sentient species that are harvested for fuel by the Harvest Rangers from Androzani major. On one instance the trees made an escape plan, seperating their life force into the body of Madge Arwell and then dispersing into the time vortex to live free while their 'bodies' were burned. They were able to create humanoid trees to interact with humans and birth them from strange silver 'baubles' that hung from their branches.