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The Hawaiian Drosophila have been a model system for evolutionary, ecological, and ethological studies since the inception of the Hawaiian Drosophila Project in the 1960s. Here we review the past and present research on this incredible lineage and provide a prospectus for future directions on genomics and microbial interactions. While the number of publications on this group has waxed and waned over the years, we assert that recent systematic, biogeographic, and ecological studies have reinvigorated Hawaiian Drosophila as an evolutionary model system. The characteristics that distinguish good model clades from good model organisms (e.g., Drosophila melanogaster) are somewhat different so we first define what constitutes a good evolutionary model. We argue that the Hawaiian Drosophila possess many desired aspects of a good evolutionary model, describe how this group of geographically isolated flies have been used in the past, and propose some exciting avenues for future evolutionary research on this diverse, dynamic clade of Drosophila. [ABSTRACT FROM AUTHOR]

The article discusses the integration of deoxyribonucleic acid (DNA) barcode data in taxonomic practice. The author states that DNA barcodes have the potential to be powerful heuristics in the identification of described species, but as of February 2011, a mindful analytic interpretation is still needed. As discussed, the role of DNA barcoding emphasizes that there is a need for recursive process of character evaluation.

The article presents a study which examines the new sets of animal phylogeny found out by scientists. It relates the studies including one by Halanych, based on a personalized supertree approach and by Dunn and his colleagues which gives a view of the patterns of divergence of animals. It examines the methods utilized by the scientists to generate their phylogenetic hypotheses. It discusses the relationships of animal taxa in the resultant trees for further clarification and examination.

The author discusses the neglect of biodiversity funding by national and international funding agencies. It states that this has led to making it a science that only focuses on human health. It informs that European Union has started a Biodiversity Program by linking biodiversity with business. Also this problem has been given several names by several authors including "the biodiversity crisis," "taxonomic imperative" and "Sixth Extinction."

In the midst of only the 6th mass extinction in the Earth's history, we must rethink how we teach evolution to prevent natural selection from being incorrectly used as a biological justification for inaction in the face of today's human‐caused mass extinction crisis. Pundits, policy makers, and the general public regularly identify the extinction of endangered species as natural selection at work, rather than attributing modern‐day extinction to the sudden catastrophic bad luck of human caused environmental change, a phenomenon distinct from natural selection. In this natural selection framing, the inability of species to survive in human altered environments is the normal progression of "survival of the fittest" and conservation measures designed to protect species is human interference with natural selection. Paradoxically, this erroneous framing of extinction as the normal course of natural selection ignores humanity's exceptional role in causing today's mass extinction crisis. Our examination of this issue in U.S. college students indicates that it arises from misunderstanding the role of extinction in the history of life, leading us to recommend a greater teaching emphasis on the distinction between extinction and natural selection, and on past mass extinction events. Also see the video abstract here https://youtu.be/29VRyirMdiw [ABSTRACT FROM AUTHOR]

The article presents a letter that attempts to clarify two issues relevant to the DNA bar coding initiative raised in an article published in the previous issue. The article enumerates and expounds the two issues namely the way the analytical approach to DNA bar coding is presented and the involvement of a broader issue with respect to the role of DNA bar coding in modern biology. The article provides a clarification to its purpose which is to be enlightened and informed.

The placozoan Trichoplax adhaerens has been bridging gaps between research disciplines like no other animal. As outlined in part 1, placozoans have been subject of hot evolutionary debates and placozoans have challenged some fundamental evolutionary concepts. Here in part 2 we discuss the exceptional genetics of the phylum Placozoa and point out some challenging model system applications for the best known species, Trichoplax adhaerens. [ABSTRACT FROM AUTHOR]

The placozoan Trichoplax adhaerens is a tiny hairy plate and more simply organized than any other living metazoan. After its original description by F.E. Schulze in 1883, it attracted attention as a potential model for the ancestral state of metazoan organization, the "Urmetazoon". Trichoplax lacks any kind of symmetry, organs, nerve cells, muscle cells, basal lamina, and extracellular matrix. Furthermore, the placozoan genome is the smallest (not secondarily reduced) genome of all metazoan genomes. It harbors a remarkably rich diversity of genes and has been considered the best living surrogate for a metazoan ancestor genome. The phylum Placozoa presently harbors three formally described species, while several dozen "cryptic" species are yet awaiting their description. The phylogenetic position of placozoans has recently become a contested arena for modern phylogenetic analyses and view‐driven claims. Trichoplax offers unique prospects for understanding the minimal requirements of metazoan animal organization and their corresponding malfunctions. [ABSTRACT FROM AUTHOR]