Biodiversity Loss and the Taxonomic Bottleneck: Emerging Biodiversity Science

Human domination of the Earth has resulted in dramatic changes to global and local patterns of biodiversity. Biodiversity is critical to human sustainability because it drives the ecosystem services that provide the core of our life-support system. As we, the human species, are the primary factor leading to the decline in biodiversity, we need detailed information about the biodiversity and species composition of specific locations in order to understand how different species contribute to ecosystem services and how humans can sustainably conserve and manage biodiversity. Taxonomy and ecology, two fundamental sciences that generate the knowledge about biodiversity, are associated with a number of limitations that prevent them from providing the information needed to fully understand the relevance of biodiversity in its entirety for human sustainability: (1) biodiversity conservation strategies that tend to be overly focused on research and policy on a global scale with little impact on local biodiversity; (2) the small knowledge base of extant global biodiversity; (3) a lack of much-needed site-specific data on the species composition of communities in human-dominated landscapes, which hinders ecosystem management and biodiversity conservation; (4) biodiversity studies with a lack of taxonomic precision; (5) a lack of taxonomic expertise and trained taxonomists; (6) a taxonomic bottleneck in biodiversity inventory and assessment; and (7) neglect of taxonomic resources and a lack of taxonomic service infrastructure for biodiversity science. These limitations are directly related to contemporary trends in research, conservation strategies, environmental stewardship, environmental education, sustainable development, and local site-specific conservation. Today’s biological knowledge is built on the known global biodiversity, which represents barely 20% of what is currently extant (commonly accepted estimate of 10 million species) on planet Earth. Much remains unexplored and unknown, particularly in hotspots regions of Africa, South Eastern Asia, and South and Central America, including many developing or underdeveloped countries, where localized biodiversity is scarcely studied or described. ‘‘Backyard biodiversity’’, defined as local biodiversity near human habitation, refers to the natural resources and capital for ecosystem services at the grassroots level, which urgently needs to be explored, documented, and conserved as it is the backbone of sustainable economic development in these countries. Beginning with early identification and documentation of local flora and fauna, taxonomy has documented global biodiversity and natural history based on the collection of ‘‘backyard biodiversity’’ specimens worldwide. However, this branch of science suffered a continuous decline in the latter half of the twentieth century, and has now reached a point of potential demise. At present there are very few professional taxonomists and trained local parataxonomists worldwide, while the need for, and demands on, taxonomic services by conservation and resource management communities are rapidly increasing. Systematic collections, the material basis of biodiversity information, have been neglected and abandoned, particularly at institutions of higher learning. Considering the rapid increase in the human population and urbanization, human sustainability requires new conceptual and practical approaches to refocusing and energizing the study of the biodiversity that is the core of natural resources for sustainable development and biotic capital for sustaining our life-support system. In this paper we aim to document and extrapolate the essence of biodiversity, discuss the state and nature of taxonomic demise, the trends of recent biodiversity studies, and suggest reasonable approaches to a biodiversity science to facilitate the expansion of global biodiversity knowledge and to create useful data on backyard biodiversity worldwide towards human sustainability

The homology of cephalic muscles and endoskeletal elements between Diplura and Ectognatha (Insecta)

Diplura (two-pronged bristletails) are key to our understanding of hexapod head evolution. A sister group relationship with Ectognatha (=Insecta), comprising bristletails, silverfish and winged insects, is advocated in most modern studies, however, homologization of head muscles and endoskeletal elements between Diplura and Ectognatha is still lacking. Here, we present the first homologization of a number of head muscles and endoskeletal structures between Diplura and Ectognatha. A homologization of these structures is possible if a range of species, both from Japygidae and Campodeidae, are studied in order to reconstruct the potential groundplan characteristics and account for inner anatomy variations within Diplura. Japygidae and Campodeidae show differences in the origin, insertion, and presence of mandibular and maxillary muscles as well as the shape of the maxillary cardo. Taking into account recent embryological studies on the formation of the endoskeleton in Protura, Collembola and Diplura, we furthermore reconstruct the potential evolution of the endoskeleton in early Hexapoda. The tentorium is a defining feature of dicondylic insects (including Archaeognatha) while anterior and posterior cephalic invaginations (the later tentorial pits of dicondylic insects) are groundplan features of Hexapoda. Additionally, we clarify the composition of the gnathal pouches (i.e. the type of entognathy) in Diplura and Collembola. The pouches in Diplura are posteriorly separated, similar to the state encountered in Collembola. This contrasts to former studies emphasizing the differences in the ellipuran and dipluran type of entognathy