Margaret Atwood started writing the novel much earlier than she expected, while still on a book tour for her previous novel, The Blind Assassin. In March 2001, Atwood found herself in the Northern region of Australia, birdwatching with her partner during a break from the book tour. Here, while watching the red-necked crakes in their natural habitat, she was struck with inspiration for the story. However, Atwood explained that the work was also a product of her lingering thoughts on such a scenario throughout her life, as well as spending a great amount of time with scientists throughout her childhood. She stated
Several of my close relatives are scientists, and the main topic at the annual family Christmas dinner is likely to be intestinal parasites or sex hormones in mice, or, when that makes the non-scientists too queasy, the nature of the Universe.
Atwood continued to write the novel through the summer of 2001 while visiting the Arctic North, witnessing global warming's effect on the region. However, shaken by the September 11 attacks, she stopped writing for a few weeks in the autumn, saying, "It's deeply unsettling when you're writing about a fictional catastrophe and then a real one happens". However, with the looming questions of the end, Atwood finished the novel for release in 2003. These questions in Oryx and Crake, Atwood explained, are "simply, What if we continue down the road we're already on? How slippery is the slope? What are our saving graces? Who's got the will to stop us?"