The fact that Selenicereus chrysocardium is endemic to the jungles of the southern Mexican state of Chiapas seems like quite a strange thing when you realise it’s a cactus. Our ideas of cactus usually revolve around bright sun, no water, and lots of spines. Most cactus species have evolved to get rid of their leaves entirely – no leaves means the plant will loose less water through transpiration – an important way to survive desert life.Somewhere along the line though, the cacti family decided to spread themselves into the shadier and more humid parts of central and southern America. All of a sudden (thousands of years in evolutionary terms) they were growing epiphytically on trees in the jungle. Because of the tropical climate, water storage became less of an issue. Lack of sun, however, meant they needed to work out ways to capture more of the golden light to enable themselves to photosynthesise.
