JOHANNESBURG - Around 65 million years ago, a massive asteroid or "bolide" smashed into the Yucatan Peninsula off the coast of southeastern Mexico, sending up a cloud of searing vapor and debris.
This effectively killed off the dinosaurs. Some were instantly vaporized, others vanished as vast dust clouds blocked out the sunlight for years.
It also ushered in what scientists have dubbed the fifth great extinction event in our planet's history.
Many scientists believe a sixth mass die-off of biodiversity is now under way because of the activities of a single species that eventually evolved from the wreckage of the previous one, and managed to colonize the earth - Homo sapiens.
In "The Sixth Extinction: An Unnatural History", American writer Elizabeth Kolbert chronicles this unfolding drama and the scientists who have brought it to life.
From climate change to the bad luck of being a flightless bird - an evolutionary advantage until confronted by hungry humans looking for easy protein - to the acidification of the oceans, Kolbert traces some of the ways we are altering ecosystems amid a growing body count of other species.
These include everything from the great auk to frogs to corals to Africa's mega-fauna - elephants and rhinos - which are currently being poached at an alarming rate.
Underscoring scientific concerns about humanity's global environmental impact, there is a movement to rename our current geological epoch the "Anthropocene".
A staff writer at The New Yorker, Kolbert spoke to Reuters by phone from her Massachusetts home about her new book and the appeal of being a cockroach.
Q: Your book has a scary theme. What frightens you most about the issue?
A: I think what is most scary, as a parent of other human beings, is what will happen from the societal disruption that could potentially result from ecological disruption and climate change. But on a 'future of the world' kind of level, what I found most sobering and frightening is what is happening to the oceans. I think ocean acidification is a kind of under-appreciated problem. And we seem to be changing ocean chemistry very dramatically and very quickly.
Q: What do you see as the biggest man-made threat to biodiversity?
A: That is hard to say. But once again when you sort of look at the record, ocean acidification looms pretty large as a driver of extinction.
Q: In the United States there is a lot of skepticism about some of these issues such as climate change. Why is that?
A: One reason is that we are just big fossil fuel users and I think people are very hesitant to acknowledge that what we consider perfectly ordinary stuff, like driving around, that that is contributing to world-altering ecological problems. I don't think that people are keen to face up to that. There is also a very concerted disinformation campaign in the United States. And this plays into this inclination that we already have, that we prefer not to believe it.
Q: If you wanted to make sure that your DNA is going to get passed on for another couple of million years, what species should you be? What species is most likely to survive the "Anthropocene"?
A: People are looking at cockroaches, which have survived relatively unchanged for quite a long time. And we know that cockroaches do really well with human disturbance. So I think if I wanted to pass on my DNA I would probably choose to be a cockroach ... If you want to pass on your genetic material, do not be a flightless bird.
Q: What is your next book project?
A: I don't know. I'm actively looking for it.