“Mystery seeds” in the post: brushing scam or international bioterrorism?

In the 1956 sci-fi classic “Invasion of the Body Snatchers,” alien plant spores fall from space and grow into large seed pods, each one capable of reproducing a duplicate copy of every human on Earth. Today — without the alien doppelgangers — frightened Brazil’s agricultural authorities warn that a similar phenomena could be in progress, after hundreds of suspicious, unsolicited packages containing mysterious seeds were sent to Brazilian homes through the post.

At least 258 samples of seeds have been turned in to authorities in all but two Brazilian states, and the Agriculture and Health Ministries have launched a joint investigation to discover whether these seeds are possible invasive plants or weeds which could be harmful to Brazil’s agribusiness, as well as finding out who is sending them — and why.

A federally-run lab in the Center-West state of Goiás analyzed some 25 packages — finding three types of fungi, as well as different types of bacteria and live...