The Clock is Ticking
- A weekly column on overpopulation, mass extinctions, global climate change, and pollution, seeking solutions to human behavior through anthropology, evolution, the social sciences, humanities, arts, and cognitive neuroscience.
- http://clockticking.com/

Musing on Beginning and End
- Thoughts on the enormity of the cosmos and the life cycle of civilizations, including our own.
- http://www.rationallink.org/beginend.htm

Beyond the Holocaust - Survival or Extinction?
- Subtitled "A survival manual for humanity", this online book attempts to summarise problems threatening humanity's very survival, their causes and possible solutions to them.
- http://www.hpn.org/beyond/

Existential Risks
- Paper by Nick Bostrom, analyzing well-known and less well-known extinction risks and related crippling hazards to humanity.
- http://www.nickbostrom.com/existential/risks.html

Book: The End of the World - The Science and Ethics of Human Extinction
- by Prof. John Leslie. The first comprehensive survey of potential catastrophes speculated upon by scientists, from comet and asteroid impacts to nuclear or chemical warfare, from ozone layer destruction to overpopulation and poisoning of the environment o
- http://www.amazon.com/exec/obidos/ASIN/0415184479

Remarks on the Doomsday Argument
- Questions if people are underestimating the likelihood of human extinction in the next few decades, a position put forward by the philosophical Carter-Leslie doomsday argument. Highly philosophical and statistical.
- http://www.anthropic-principle.com/preprints/inv/investigations.html