What does that mean, mass extinction, it means simply that the majority of species on Earth will disappear in a very short period of time.
Sean B Caroll is hosting a documentary starting on Dec 1, 2014 on the Smithsonian Channel. If you have the ability, I would advise viewing the program. It was very enlightening.
Here is a sneak peak --> http://www.smithsonianchannel.com/sc/web/show/3413789/mass-extinction-life-at-the-brink#the-surprising-culprit-threatening-yellowstones-grizzly-bears
Here is an article in Salon with an interview of Sean B Carroll talking about the documentary and mass extinction. --> http://www.salon.com/2014/11/30/things_are_disappearing_on_earths_looming_mass_extinction_and_what_to_do_about_it/?utm_source=facebook&utm_medium=socialflow
So, if this idea of a new mass extinction happening during our lifetime. What do you think the world and more importantly your world will look like.
How will the diversity be effected? Is less diversity important? How are some of the impacts of less diversity can affect your life? Is there anything the average individual can contribute to the upcoming doom and gloom predict.
This is going to get much more attention in the very near future.
If you get a chance - watch the documentary.