Current biodiversity crisis is often compared to the five mass extinctions in geological history. Here I review the evidence concerning current global extinction, showing that its extent is so far much smaller than was in the case of the five big extinction events.
However, global extinction rate is currently quite high, so that if the rate remains the same, the magnitude of the sixth global mass extinction could be reached within next several hundreds years. The tropics are now much more vulnerable to animal and plant extinction than is the temperate zone.