The first mass extinction was the Ordovician-Silurian extinction caused by intense glaciation of Gondwana that eventually led to a snowball earth.
A possible cause was the intense glaciation of Gondwana, which eventually led to a snowball earth. The first mass extinction was the Ordovician-Silurian extinction.
The first mass extinction was the Ordovician-Silurian extinction. A possible cause was the intense glaciation of Gondwana, which eventually led to a snowball earth.
The first mass extinction was the Ordovician-Silurian extinction. A possible cause was the intense glaciation of Gondwana, which eventually led to a snowball earth.