Why Is The Brush Tail Possums Considered Microevolution?

Environmental change plays an important role in evolution. When an environmental change occurs, it can be a physical or chemical change. It can also be a gradual process such as the formation of mountains, or it can be a rapid and unexpected change, such as a natural disaster. When changes in organism’s environments occur, they must adapt to their new environment, this can cause ample amounts of selective stress and pressure on organisms, causing some species to eventually die out, while other organisms strive and evolve to be better adapted to this change.

An example of a species that has undergone a change due to an environmental alteration, is the Brush Tail Possum (Trichosurus vulpecular). The Brush Tail Possum is native to Australia and was introduced into New Zealand in the 19th century for the purpose of gathering fur for the fur industry. However, the species thrived in this environment and is now considered an agricultural pest. The possum can also carry a disease called

Microevolution refers to the change of a gene frequently within a specific species. Such changes may be accomplished by natural selection as a specific trait may become favourable in a set of environmental conditions. This trait may help the species survive and is therefore passed onto offspring and becomes more frequent in the species. Evolution on this scale can be observed over short periods of time. For example, when there is a chemical change in an environment and the species adapt to be better suited to this change, this is considered microevolution.

Macroevolution however, refers to evolution on a much larger scale. Macroevolution refers to the evolution of groups larger than an individual species and concentrates on change over a much larger time frame. Macroevolution studies the change of species into a new type of species in contrast to microevolution which studies change within a