 It is time for Ask the Unexpected and this week we've had a question from Matthew who asks which animal has the worst carbon footprint? This caused a bit of a stink in the office as everyone thought about it, but we've found someone who can give us an answer. My name is Guillermo Pardo and I work at the Basque Centre of Climate Change, which is in the north of Spain. OK, and this is what Dr Pardo had to say.