The Holocene is the ongoing part of the Quaternary Era, ie, the last 10-12 thousand years up to NOW. It appears that we humans are causing more extinction than usual. We're not sure if humans should be blamed for the early Holocene extinction of the woolly mammoth, North American horses, sabertooth cats and some other megafauna. They expired when humans were organized bands of ravenous hunters. Maybe we hunted them out. Or maybe climate change got them. Hard to know. Now we are taking all the world's resources for ourselves, and "laying siege to all life on earth". It's harder to argue now that we might not be to blame.
I can barely believe the commenters who say there is no connection between what is natural and what is desirable.
Great article on human evolution and extinctions:
http://anthropik.com/2005/07/the-holocene-extinction/ Fungus is killing the bats and the bees:
http://www.cjr.org/the_observatory/the_bats_and_the_bees.php The Holocene extinction:
http://arstechnica.com/journals/science.ars/2008/02/20/the-holocene-extinction-rumbles-on-bat-edition