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.
Genetic diversity (amount of genetic variability among individuals of the same species) and ecological diversity (number and relative abundance of species) are both components of biological diversity.enetic diversity (amount of genetic variability among individuals of the same species) and ecological diversity (number and relative abundance of species) are both components of biological diversity.