Lava Flow May Have Caused Extinction

Pinhead writes "From MSNBC, it appears a new study suggests that a massive extinction that occurred 250 million years ago may not have been an asteroid but a large lava flow that spewed large amounts of poisonous gases in the air. This extinction led to the rise of the dinosaurs." Note that there are two different big extinctions: this first one occurred when plant life was mostly ferns, and all the continents were together in Pangaea. The later one is the one that everyone knows about, that wiped out the dinosaurs.