The Welwitschia of Namibia, whose two leaves
grow continuously for centuries.

A study mapping the world’s terrestrial regions that host multiple ancient lineages, has been published by an international team led by Professor Serban Proches of UKZN’s Discipline of Geography in the School of Agricultural, Earth and Environmental Sciences (SAEES).

The team includes Dr Syd Ramdhani of the School of Life Sciences.

This study, published in the prestigious Scientific Reports journal of the Nature Publishing Group, maps the global hotspots in the present-day distribution of ancient animal and plant lineages. These lineages are groups of animals and plants that date back to Cretaceous and Triassic days, about 66 million years and 199 million years ago respectively.

This study has important implications for the conservation of the ancient plants and animals it deals with.

‘Among localised lineages of such venerable age is the Welwitschia of Namibia – a shrub with only two leaves that grow continuously for centuries, and New Zealand’s tuatara, a lizard-like creature whose kind has seen dinosaurs come and go,’ said Proches.

Proches explained that when the distributions of such lineages were summed up and mapped, interesting patterns emerged. He said narrowly-distributed Cretaceous-age lineages were concentrated in several Southern-Hemisphere hotspots, including South Africa’s Cape Floral Kingdom, but also parts of South America, South-East Asia, and Australia.

‘Triassic lineages are interesting in that they do not follow the common rule dictating that most species or lineages are to be found in the tropics – many Triassic-age lineages are restricted to North America and temperate Eurasia,’ said Proches. ‘Many such animals and plants, after having survived for tens or hundreds of millions of years, are now threatened by anthropogenic changes in the environment, and maps indicating hotspots in their distribution are critical in ensuring their continued survival.’