Almost all plants photosynthesise, but not all in the same way: there are three pathways through which plants can convert carbon dioxide into the sugars that fuel plant growth and development. About 90% of plant species use ‘C3’ photosynthesis, absorbing carbon dioxide during the day; about 7% use ‘C4’, which operates in a similar way but has different biochemistry behind it. The remaining 3% of plant species use CAM photosynthesis, and the Tar Gum Tree is the only tree which does so. Surprisingly, it also utilizes C3 and C4 photosynthesis, and can swap between photosynthesis types depending on environmental conditions. It can even use different pathways in different parts of the same leaf at the same time. 

Integral to CAM photosynthesis are daily rhythms where the stomata remain closed during the day and open at night when it is cooler. C3, C4 and CAM photosynthesis are all governed by the circadian clock. 

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