Synopsis: Multiple deadly new strains of H5N bird flu are successively infecting poultry farms across the globe. These pathogens are killing millions of farmed birds and threaten human outbreaks. Thanks to industry-funded research, blame is usually placed on wild bird populations and climate change. According to new research, however, the real culprit is escaping that judgment. It is factory farm conditions such as cramped housing, genetic uniformity, and the rapid cycling of birds.