The gastrointestinal (GI) tract is teeming with an extremely abundant and diverse microbial community. The members of this community have coevolved along with their hosts over millennia. Until recently, the gut ecosystem was viewed as black box with little knowledge of who or what was there or their specific functions. Over the past decade, however, this ecosystem has become one of fastest growing research areas of focus in microbial ecology and human and animal physiology. This increased interest is largely in response to studies tying microbes in the gut to important diseases afflicting modern society, including obesity, allergies, inflammatory bowel diseases, and diabetes. Although the importance of a resident community of microorganisms in health was first hypothesized by Pasteur over a century ago (Sears, 2005), the multiplicity of physiological changes induced by commensal bacteria has only recently been recognized (Hooper et al., 2001). The term 'ecological development' was recently coined to support the idea that development of the GI tract is a product of the genetics of the host and the host's interactions with resident microbes (Hooper, 2004). The search for new therapeutic targets and disease biomarkers has escalated the need to understand the identities and functions of the microorganisms …

Comprehensive Federal fleet management guide offered as a companion to Executive Order 13514 Section 12 guidance.