A pair of recent stories are pointing to the growing and increasingly human impacts of global warming.

First in the high Arctic, scientists are reporting that some species of plants and animals have begun their annual cycles as much as 30 days earlier in just the past ten years.

In some cases, flowers are emerging from buds and chicks are hatching a full 30 days sooner than they did in the mid-1990s in response to sharply increased temperatures burning off the winter's snow layer.

But while arctic song birds see the light of day a month earlier, climate change is also being implicated as a major factor in Darfur, Sudan where 200,000 have died in an ongoing ethnic conflict. The link was drawn by U.N. Secretary-General Ban Ki-moon said in an editorial published Saturday.

It would be natural to view these as distinct developments. In fact, they are linked. Almost invariably, we discuss Darfur in a convenient military and political shorthand -- an ethnic conflict pitting Arab militias against black rebels and farmers. Look to its roots, though, and you discover a more complex dynamic. Amid the diverse social and political causes, the Darfur conflict began as an ecological crisis, arising at least in part from climate change.

The connection between ecological strain and war was convincingly presented in Jared Diamond's chronicle of the Rwandan genocide featured in his acclaimed book Collapse. The key point in the issue is that as we enter an age of increasing shortages of food and water, warfare and genocide will act as the face mask worn by a true root cause of human generated climate change.