A tiny shaving of enamel from the tooth of a long-dead zebra or a recently dead lion can be the puzzle pieces that help archaeologists piece together a picture of what Africa’s climate might have looked like during the time when our early ancestors were evolving on the African savannah.

Enamel in a person’s tooth holds the secret to what that person ate as a child. Bone tissue in the tibia shows someone’s diet over a lifetime. Their hair will show what the person ate in the last few months of their life. Putting this kind of tissue through isotopic analysis is contributing towards advances in human forensics. 

The entrance to a nondescript cave on a south-facing slope of the Swartberg Mountains, overlooking the Little Karoo, holds in its earthen floor a history of dramatic climatic change, and hunter-communities who were climate refugees as a warming world inundated their foraging grounds with a rising ocean. 

In poaching circles, cycads are for the plant community what rhinos are for wildlife. As the illegal trade continues apace, conservationists are adding isotopic analysis to the toolkit of measures to protect trees whose lineage goes back to the time of the dinosaurs.

The coppersmiths of ancient Zimbabwe sourced their ore from the same mineral-rich belts in sub-Saharan Africa that supply today’s mining industry. Modern isotope technology is allowing archaeologists to trace the precise locations of the ores they smelted and mixed, showing a complex trading network and technological exchange across the region, with Great Zimbabwe the economic engine room at the centre of it.

In the past century, humans’ mastery of synthetic fertiliser production has allowed us to turn inert nitrogen into a super-fuel that helped double Earth’s food production capacity. But how much has this upended the natural nitrogen cycle? A tiny weather station on a peninsula just south of Cape Town is helping researchers understand change at a planetary scale.

The illegal wildlife trade is a serious conservation threat on the African continent. Advances in isotope studies allow this technology to be used widely to counter animal trafficking. It can help trace an animal’s origins, map poaching hotspots, uncover wildlife trading fraud, or build a forensic timeline.

An intimate portrait emerges of a San hunter-gatherer clan from about 3,000 years ago, whose favourite haunt was a peninsula that juts into Plettenberg Bay. After almost five decades of breaking new ground in the field, pioneering African archaeologist Professor Judith Sealy recounts a story that remains close to her heart.

The weight of a water molecule’s parts can tell how it has travelled through a river basin. Other isotopes in a water sample can tell its age. A trip to South Africa’s Calitzdorp and Warmwaterberg hot springs reveals the secrets of long-haul groundwater travel.