However, not all pension plans allow such withdrawals. Many pension plan rules do not allow in-service distributions, or withdrawals while you are still in service with the company. Some defined benefit pension plans do not allow early distributions at all. Others, such as some 401k plans, allow workers to make withdrawals at any time.
These indices not only measure species richness, but also take into account the relative abundance of species, or evenness. When measuring species diversity, species richness and evenness must always both be considered. In addition, indices provide important information about species rarity and commonness in a population. These are important and common tools used by biologists in order to understand community structure.
Biodiversity is More than Just Species. Species diversity is only one part of biodiversity. To properly catalogue all the life on Earth, we also have to recognize the genetic diversity that exists within species as well as the diversity of entire habitats and ecosystems.iodiversity is the variety of life. It can be studied on many levels. At the highest level, you can look at all the different species on the entire Earth. On a much smaller scale, you can study biodiversity within a pond ecosystem or a neighborhood park.