Biodiversity started out as a contraction of biological and diversity. It was coined in 1985, but has taken on its own meaning since then.
Scientists prefer using the broadest possible biodiversity definition, to not overlook any aspect of what is an exceedingly complex subject. However, one of the largest problems facing scientists, government agencies, end environmental groups is how exactly, to define biodiversity. Dictionaries are generally silent anything more than the most general outline of the subject, but most have some elements in common. Most take into account that a it must reference the number and variety of plants and animal species, and that these species occupy a particular geographic region. Some include the concept of the variability of those plants and species. One or two include the variability within and among ecosystems, as well as within and between living organisms.
One of the best biodiversity definitions we have found comes from The Center for International Environmental Law: Biodiversity is the variability of all living organisms, including animal and plant species, of the genes of all these organisms, and of the terrestrial, aquatic and marine ecosystems of which they are part.
Developing a biodiversity definition is problematic no matter who is doing it because biodiversity is a very broad topic and includes everything, making it very hard to exclude anything. For example, while every biodiversity definition includes plant and animal life, not all include the soil or water that sustains that life, although to be totally fair, most do so. Further, not every biodiversity definition includes human beings. Complicating the matter even more is the problem of whether a real, comprehensive biodiversity definition should include only those species that humans find useful, or all the given plant and animal species of an area.
With such differences, it is almost impossible to come to a conclusion about the meaning of the term, let alone the scope of the topic. Add in the differing agendas of all those who claim to be concerned about biodiversity, and those who claim to want to do something about it, and you have a situation more confusing than resolvable. Then add in those who insist that nothing can be done because there is no way biodiversity and progress can coexist. Clearly, if something cannot be defined easily and concisely, how can the issues presented by it be prioritized, let alone having resources allocated to resolve them?
Given the difficulties of establishing a unified, comprehensive biodiversity definition, the question is less which definition should prevail, but more what we do to preserve biodiversity.