David Grinspoon Quote
The Big Five extinctions are simply slightly more intense than the sixth- or seventh-largest declines, and you could just as easily discuss the Big Seven or Big Ten, depending on how you sliced up the data. This tally refers only to extinctions since the Cambrian explosion, the sudden proliferation of complex animal life 542 million years ago, and it neglects extinction events that happened earlier, during several billion years of evolution dominated by simpler organisms. So, though the changes occurring right now are often referred to as the beginning of a possible sixth extinction, take this with a grain of salt. It’s good to focus attention on the dramatic loss of species currently under way and how this fits into the history of extinction events on Earth, but this also reinforces an incomplete picture of Earth’s dynamic history. Post-Alvarez,
The Big Five extinctions are simply slightly more intense than the sixth- or seventh-largest declines, and you could just as easily discuss the Big Seven or Big Ten, depending on how you sliced up the data. This tally refers only to extinctions since the Cambrian explosion, the sudden proliferation of complex animal life 542 million years ago, and it neglects extinction events that happened earlier, during several billion years of evolution dominated by simpler organisms. So, though the changes occurring right now are often referred to as the beginning of a possible sixth extinction, take this with a grain of salt. It’s good to focus attention on the dramatic loss of species currently under way and how this fits into the history of extinction events on Earth, but this also reinforces an incomplete picture of Earth’s dynamic history. Post-Alvarez,