For humans, forest fires, such as the one that scorched 85,000 acres atop Mount Lemmon last summer, are tragic. But they are natural and necessary events for healthy forests, tree-ring studies show. If land managers had known this a hundred years ago, they could have prevented catastrophic wildfires that now threaten forests throughout the Southwest.
Africa, a continent beset by poverty, civil wars and a catastrophic AIDS epidemic, now has one more worry – global warming. A team of researchers, led by University of Arizona geosciences Professor Andrew Cohen, has determined that regional climate shifts paralleling global warming patterns have caused fish yields from Africa’s Lake Tanganyika to drop by about 30 percent over the past 80 years, and could produce further declines in the future. read story
Freeloaders, it seems, show up everywhere in nature, not just at the company picnic. Pine bark beetles, upon discovering a suitable tree to lay their eggs, emit a pheromone to muster thousands more beetles to the find. Most of the beetles that arrive collaborate to infect the tree with fungi that will kill it. A few freeloaders, though, may accept the airborne invitation without participating in the attack, instead lingering to lay their eggs in the tree which the others have invested their energies to prepare. read story