[The Conversation Africa] Madagascar has many "mini" creatures. These include a recently discovered group of miniaturised frogs as well as the discovery earlier this year of the smallest reptile on earth - the Brookesia nana, or nano-chameleon, which is the size of a paperclip. Moina Spooner, from The Conversation Africa, asked Dr Mark D. Scherz, an amphibian and reptile specialist who focuses on Madagascar, to explain what causes these animals to miniaturise.