MSc/MPhil in Biodiversity, Conservation and …
Complex animal life evolved sometime over 500 million years ago. Since that time, life has continually evolved into different groupings of strange and diverse forms. Today, however, is a unique and unprecedented instant during this extraordinarily long history of life. Never before has there been a creature such as us—a being with the ability to rapidly and radically change the world. Only those who are blind to Nature can look around and not see catastrophe as growing thousands of species are pushed into the dawnless night of extinction.
Stations of the Cross | Reflections
So self-absorbed are we that the last consequence is the least mentioned. But it is the most important and long-lasting result of the human population explosion. Of the five, it is the most obvious and well-documented right now. The murder of Earth’s biodiversity and evolutionary potential will alter the future in ways we cannot foresee. Judging by earlier mass extinctions, it can take millions of years for recovery. And this will be the human legacy—to have behaved like an asteroid? Conservationists within the population discussion must stress how the human population explosion kills Earth’s life. Those who claim to love the wild, to love Nature, to love what has birthed us, are proclaiming a false love if they are unwilling to tackle human population growth or at least acknowledge it.
Biodiversity among areas can be compared with statistical indexes of species diversity (Magurran 1988; Pielou 1975). Most indices combine two different metrics: the total number of species and the relative abundances of all species (evenness) in a sample. Such indexes have been criticized on the grounds that similar values of an index might reflect quite different sample compositions. A given index value could reflect a high species richness (a large number of species, many of them rare) or could be attributed to many fewer but commoner species (for example, high relative abundance of many species).
What is Human Biodiversity? | hbd chick
Biodiversity includes not only the world's species with their unique evolutionary histories, but also genetic variability within and among populations of species and the distribution of species across local habitats, ecosystems, landscapes, and whole continents or oceans. Understanding what constitutes and defines biodiversity is essential for managers and policy-makers who must attempt to incorporate its values into their land- and water-management plans. It is only when we understand all the interacting scientific dimensions of biodiversity outlined in this chapter that we can appreciate the levels of information that must be considered. Biodiversity-management options are inevitably constrained by a combination of biological and sociopolitical realities. In this chapter, we present our biological understanding of biodiversity, which provides the basis for further chapters and , which consider the "uses" and "value" of biodiversity.
Election Reflections and an Open Letter to Donald …
The role of ecological interactions in influencing whether species can coexist locally has been recognized at least since the time of Darwin (1859), who showed that a clipped grassy plot harbored more species than an undisturbed one. Since then, an extensive literature has developed the theme that various interactions can influence the genetic structure and morphological appearance of local populations (Tollrian and Harvell 1999), the probability of species coexistence (Paine 1969), and the biological structure and function of entire freshwater assemblages (Brooks and Dodson 1965; Carpenter and Kitchell 1993; Werner 1986). Probably all known taxa, ranging from pathogens to (especially) humans, are involved in this interactive natural world. The dynamic relationships and their immediate and long-term consequences obviously influence the determination and evaluation of species diversity patterns.
Reflections on the Climate Change Conference in …
Biodiversity includes not only the world's species with their unique evolutionary histories, but also genetic variability within and among populations of species and the distribution of species across local habitats, ecosystems, landscapes, and whole continents or oceans. Because biodiversity is such a broad concept, methods for its quantification are necessarily broad. In this chapter, we have attempted to define the components of biodiversity and to describe some of the ways to measure them. In the following chapters, case studies illustrate management decisions driven by various concepts of what biodiversity is or does. For instance, aesthetic considerations were influential in the preservation of open spaces in Boulder, CO (), whereas water quality issues motivated the restoration of Lake Washington (). The Everglades case study describes a major federal project in which biodiversity itself and habitat restoration were the primary considerations (). Given such variation in mission, managers must consider both the maintenance of viable local populations of species of interest and the maintenance of biodiversity on larger scales, which is essential for the functioning of ecosystems. This chapter has addressed the many components of biodiversity that managers need to consider; the next chapter extends our understanding of how people value the components of biodiversity. Throughout the report, case studies illustrate management decisions that were based on the varied biodiversity components.