A forgotten Permian extinction wiped out reefs millions of years before the Great Dying
For decades palaeontologists lumped it in with the catastrophe that ended the Permian. Only in 1994 did they recognise a separate collapse, some 259 million years ago, that may have killed around six in ten species. Its likely trigger was a burst of volcanic eruptions in what is now southwest China.
The Capitanian extinction is named after the final stage of the Middle Permian. It began roughly 262 million years ago and hit hardest around 259 million years ago, a few million years before the far larger end-Permian disaster. By some counts it removed a third of all genera and more than 60 per cent of species, ranking third among the great die-offs of the last half-billion years. Other researchers see it as a regional or drawn-out decline rather than a single global blow, and its timing is still argued over.
Its likely cause sits in the rocks of the Emeishan Traps, a vast outpouring of lava interleaved with tropical limestone platforms. Explosive eruptions, as magma met water, coincide with the disappearance of reef-building algae and large single-celled foraminifera there, making the site unusual for preserving both an extinction and its probable trigger. A 2026 study of ash layers dated the end of the Middle Permian to about 259.86 million years ago, at the start of a second major volcanic pulse.
Shallow tropical seas suffered most, especially creatures that relied on sunlight directly or through symbiotic partners. Around South China the reef system collapsed, taking with it giant bivalves called alatoconchids and most coral species. At Spitsbergen, 87 per cent of brachiopod species vanished over tens of thousands of years, and afterwards bivalves took over the role that brachiopods had long held. In some tropical settings brachiopods had made up nearly all individual shells before the event; afterwards molluscs were the majority.
On land the picture is patchier. In South Africa's Karoo Basin, tetrapod genera fell by roughly three quarters, including the dinocephalians, large mammal-related animals that had dominated their ecosystems, and recovery there stayed sluggish for at least a million years. In North China more than half of recorded plant species disappeared.
Source: Capitanian mass extinction event
