Spatial & Temporal Distribution of Microbes
What paradox, formulated by G. Evelyn Hutchinson, asks why hundreds of phytoplankton species stably coexist in uniform surface waters rather than a single superior competitor driving all others to extinction?
The Paradox of the Plankton.
Which molecular marker gene is universally used to identify and classify bacteria and archaea because it contains both conserved regions for universal primers and hypervariable regions for taxonomic identification?
The 16S rRNA gene.
Which global environment ranks highest in overall microbial diversity due to spatial micro-structures and sharp vertical chemical gradients?
Marine sediments.
What is the name of the phenomenon where direct microscopic counts reveal billions of bacterial cells per gram of soil, yet less than 1% of those cells successfully form colonies on nutrient agar plates?
The Great Plate Count Anomaly.
What shared evolutionary trait do dominant oligotrophic microbes across different phyla, such as SAR11 in oceans, the acI clade in lakes, and DA101 in soils possess to maximize resource efficiency in nutrient-poor waters and soils?
A streamlined (or exceptionally small) genome.
What pragmatic, gene-based proxy for "species" groups 16S rRNA gene sequences that share 97% or greater sequence similarity?
An OTU (Operational Taxonomic Unit).