Biological species concept

Ziqtara, M.S. and Lumme, J. (2003) The crossroads of molecular, typological and biological species concepts two new species of Cyrodactylus Nordmann, 1832 (Monogenea Gyrodactylidae). Systematic Parasitology 55, 39-52. 

A Local Flora and the Biological Species Concept. American Journal of Botany 79 222-238. 

Sokal, R.R. and Crovello, T.J. (1970) The biological species concept a critical review. American Naturalist, 104 127-153. 

The units one has to work with, the taxa from low to high, may be fixed, about the contents of these concepts a number of questions can be asked. Partly these questions are philosophical (does a species, a genus really exist in nature or only in the human mind ), partly they are quite practical (to which criteria must species, genera etc. answer ). Especially about the species concept there has been a lot of discussion and opinions did and do differ. For many a species is a unit that has to be morphologically recognizable with preferentially two constant differences with other species, for others the species is more or leas identical with the hybridization com-munity. Genet.ical "identity" of the components of a species is an important criterium and may lead some to forbid different chromosome numbers within one species. The battle about "biological and "taxonomical or less clear event linnean)" species started in the forties when herbarium taxonomists were confronted with students of... 

This definition is known as the biological or genetical species concept, because of its emphasis on reproductive isolation,... 

Cracraft J. Species concepts in systematics and conservation biology—an ornithological viewpoint. In Claridge MF, Dawah HA, Wilson MR, eds. Species The Units of Biodiversity. London Chapman Hall, 1997, pp 325-339. 

Modem taxonomists do more than just discover and describe species. They record data related to their specimens or strains as well and pubUsh them directly on the Internet. It is now possible to build data-bases of experiments, strains and species and to use a diversity of tools and algorithms to compare OTU. The reference systems based on biological, phylogenetic and/or phenetic species concepts can be used together with additional reference systems at other levels, such as the strains, for example. In addition, many taxonomically uninformative or non-relevant criteria can be introduced in data-bases dedicated to researchers working in industrial or clinical settings. This enables a wider use of such data-bases and will hopefully attract more attention to the work of the new taxonomists developing such resource centres. 

Sol-gel-derived silane-based materials have been proven as a suitable matrix for entrapment of bioactive species, due to biocompatibility of silica and the mild operating conditions. We recall that the solutions used for cathodic electrochemical deposition of silane-based sol-gel films are usually mild acidic (pH 3-6), and the deposition is achieved by electrochemically driving the inter- cial pH near the cathode to mild basic, about pH 8. This environment is favorable for maintaining the activity of biological species such as proteins, enzymes, and bacteria. Many researchers have reported the fabrication of biosensing films by co-electrodeposition of silane with different bioactive substances. The essence of the concept is to entrap bioactive substances within the sol-gel matrix during... 

Chemical substances are the central kinds of chemistry and are as important to imderstanding chemistry as the species concept—or concepts—is to understanding the biological sciences. There are three long-standing questions about substances (i) What makes something a sample of the chemical substance that it is (ii) What kinds of change can an exemplification of that substance survive (iii) What is the difference between pure compound substances and mixtures Indeed can such a distinction be drawn at either the microscopic or the macroscopic level ... 

Mace, G. M., Marshall, J. C. and Purvis, A. (2004). The impact of species concept on biodiversity studies. Quarterly Review of Biology, 79 161-179. 

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