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The Karoo regions of South Africa are
acknowledged as the richest collecting grounds for therapsid fossils
in the world. These vertebrate fossils, commonly known as mammal-like
reptiles, record in detail the evolutionary transition of reptiles
into mammals. Palaeontologists from overseas have visited South Africa
for decades to study the Karoo collections. Their abundance and
diversity reflect an ecosystem that was as developed as that of the
savanna plains today and allows researchers the opportunity to study
changes in terrestrial ecosystems over millions of years. The Karoo
strata contain a nearly continuous record of life and environmental
conditions in the continental lowlands of southern Gondwana, dating
from the Late Carboniferous to the Early Jurassic (300-190 million
years ago). It is the thickest, best exposed and stratigraphically the
most nearly complete terrestrial succession of this age of all the
Gondwanan countries.
Fossils in the Beaufort Group strata document the major extinction
event that devastated the earth’s biota at the end of the Permian
about 250 million years ago, and how the terrestrial ecosystem
recovered. This research programme includes a project aimed at
searching this stratigraphic interval for clues as to what caused this
"Mother of all extinctions". The aim is to learn more about past life
on Earth and the environmental changes that have taken place on a
continent over geological time. Such changes are happening now at such
almost imperceptibly slow rates that their cumulative effects may only
be measured over thousands to millions of years. The rocks and fossils
of the Karoo Basin record these cumulative changes in the terrestrial
conditions on the southern continents over at least 50 million years.
This research is aimed at reconstructing the changing landscapes and
biota of southern Gondwana and probing for the probable causes.
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