A Systematic, Complexity-Reduction Approach to Dissect Microbiome: the Kombucha Tea Microbiome as an Example

One defining goal of microbiome research is to uncover mechanistic causation that dictates the emergence of structural and functional traits of microbiomes. However, the extraordinary degree of ecosystem complexity has hampered the realization of the goal. Here we developed a systematic, complexity-reducing strategy to mechanistically elucidate the compositional and metabolic characteristics of microbiome by using the kombucha tea microbiome as an example. The strategy centered around a two-species core that was abstracted from but recapitulated the native counterpart. The core was convergent in its composition, coordinated on temporal metabolic patterns, and capable for pellicle formation. Controlled fermentations uncovered the drivers of these characteristics, which were also demonstrated translatable to provide insights into the properties of communities with increased complexity and altered conditions. This work unravels the pattern and process underlying the kombucha tea microbiome, providing a potential conceptual framework for mechanistic investigation of microbiome behaviors.

REVIEW OF THE SEVENTH EDITION OF AMERICAN FOREIGN POLICY: PATTERN AND PROCESS

The article presents key points of the reviewed book and introduces central ideas written by the authors.

Lineage Identification Affects Estimates of Evolutionary Mode in Marine Snails

In order to study evolutionary pattern and process, we need to be able to accurately identify species and the evolutionary lineages from which they are derived. Determining the concordance between genetic and morphological variation of living populations, and then directly comparing extant and fossil morphological data, provides a robust approach for improving our identification of lineages through time. We investigate genetic and shell morphological variation in extant species of Penion marine snails from New Zealand, and extend this analysis into deep time using fossils. We find that genetic and morphological variation identify similar patterns and support most currently recognized extant species. However, some taxonomic over-splitting is detected due to shell size being a poor trait for species delimitation, and we identify incorrect assignment of some fossil specimens. We infer that a single evolutionary lineage (Penion sulcatus) has existed for 22 myr, with most aspects of shell shape and shell size evolving under a random walk. However, by removing samples previously classified as the extinct species P. marwicki, we instead detect morphological stasis for one axis of shell shape variation. This result demonstrates how lineage identification can change our perception of evolutionary pattern and process. [Genotyping by sequencing; geometric morphometrics; morphological evolution; Neogastropoda; phenotype; speciation; stasis.]

Pattern and Process in Evolution: Unfolding Nature’s Origami

Pattern and process are central concepts to understanding the evolution of behavioral traits for comparative psychologists. Origami is an art form which involves application of pattern and process to produce a wide array of objects using paper. Because of origami’s parallels with evolution, both of morphology and behavior, it can serve as a concrete and accessible analogy for students of comparative psychology. Origami’s processes can be reversed by unfolding the paper, thereby revealing patterns common across designs. Likewise, by studying pattern and process in evolution, scientists unfold nature’s origami. Application to comparative psychology and pedagogy are discussed.