If at the beginning of life spawning on Earth every living thing belonged to the same species then this was so until genetic diversity evolved. Therefore let me apply a definition I've had for a species to life itself as it must have been in terms of lacking in variation as one single organism type at the very beginning.
A known species (Life is....) is a described self replicating biochemical unitary temporal approximation.
If RNA viruses are predatory on ribosomes then RNA precursors of self replication and synthesis in living chemistry came first. Perhaps RNA evolved to be predatory on other types of RNA as an exaptation of genetic information transfer? See See http://www.sciencedaily.com/releases/2012/11/121120132906.htm
The latter is something I'd proposed at http://saganet.org/forum/topics/s-a-g-a-n-discussion-of-the-week-10
It is hard to understand why Congress cannot put the dots together when it comes to basic research and economic development. In my opinion, the matter should be "crystal clear." Research and development has been the driving force for economic development since the dawn of time. One need not look any further than "ancient Greek history." The nation-states of ancient Greece thrived (and left a rich legacy to the world) while their economy remained focussed upon using technology and learning for the public good.
It sounds as if congressional staffers need reading material (as do the representatives of Congress). Asking to justify astrobiology research (or any research for that matter) shows the shortsightedness of Congress.
I plan to e-mail my congressional rep and senators as well--and urge them to "see" the connection between economic well-being and R&D (space science--and basic research).