Read this article to learn about categories and census of threatened species. Categories of Threatened Species: The major IUCN threatened categories (IUCN Red List Categories, 1995) currently recognised, together with their definitions! (i) Extinct (EX): Species not definitely located in the wild during the past fifty years but which may survive in cultivation (e.g. Franklinia aloetamha). Some authors suggest that [...]
Brief outlines of the two types of diversity indices of biodiversity are discussed in this article. The two types are: (1) Dominance Indices, and (2) Information-Statistic Indices. 1. Dominance Indices: Dominance indices are weighted toward the abundance of the commonest species. A widely used dominance index is Simpson's diversity index. It takes into account both richness and evenness. Simpson's Diversity [...]
This article provides study notes on global biodiversity. 1.4 million Species of various life-forms have been enlisted so far. These include 300,000 species of vascular plants; 40,000 species of vertebrates; 800,000 species of insects; 360,000 species of microorganisms (Table 1). However, these estimates are increasing all the time. A conservative estimate of the total figure would be 14 million. According [...]