Over at Slate there's a nice piece that starts:
Here’s a forensic riddle: Ten people eat an autumn dinner of roasted quail in Turkey. Hours later, four diners start to vomit. They grow weak. Their muscles ache. At the emergency department, they’re diagnosed with rhabdomyolysis—a life-threatening syndrome that afflicted people who survived being crushed under rubble during the London bombing raids in World War II.
Except this is 2007 in Turkey. And instead of Luftwaffe raids, these four men are the victims of a poisonous bird.
The European quail has been killing some — but not all — of its human predators for millennia. But only in the past three decades have researchers looked for other poisonous birds in the Americas, Australia, and New Guinea. These are birds that possess unfamiliar toxins and should, biologists say, be explored and understood for their medical potential.
Read the rest here. The bottom line is that the toxins are from plants and animals the birds eat, and the divergent reactions are a combination of dosage and varying genetic susceptibility to toxins among people.