What is the link between the Negev desert and space faring?

Negev desert (credit: vosizneias.com)

Hello everyone!
Can living beings survive a journey of years through interplanetary space?

The Planetary Society is testing whether 10 distinct organisms could survive such a long journey in interplanetary space with the LIFE (Living Interplanetary Flight Experiment) launched on board Russia's Phobos-Grunt ("soil") mission.

Since only ten organisms could be selected for the trip, the stakes in choosing the right ones were high. Read more >>>

The last organism to be integrated in this experiment is some soil from the Negev desert. What kind of extremo-soil is this Negev desert soil to be sent into space? I started to wander why would they want to send soil from this desert. all other organism are some sort of "living bacteria" crudly speaking, but the Negev soil is just soil, so what did the Planetary society had in mind when they sent this soil sample?
Now as the mission is in peril, we can only hope and wait to see if the Russian Phobos-Grunt "soil" mission will get to the red planet and complete its journey back to Earth with more answers surrounding our solar system origins.
wiki: Negev desert

Tapani Isomäki
Kustavi, Finland