What Is Wallace Definition?

Wallace Definition

Wallace definition refers to the concept of genetic differentiation between populations of a species due to geographic isolation. This process often leads to the formation of new species over time.

The term "Wallace definition" is named after Alfred Russel Wallace, a British naturalist who independently developed the theory of evolution by natural selection alongside Charles Darwin. Wallace's work on the distribution of species in the Malay Archipelago provided evidence for the role of geographic isolation in the evolution of new species.

How Does Wallace Definition Work?

Wallace definition occurs when a population of a species becomes geographically isolated from the rest of the species. This isolation can be caused by a variety of factors, such as mountain ranges, rivers, or oceans.

Once a population is isolated, it can begin to evolve independently of the rest of the species. This is because the isolated population is no longer able to exchange genes with the rest of the species, which can lead to genetic drift and the accumulation of new mutations.

Over time, the isolated population can become so genetically different from the rest of the species that it is no longer able to interbreed with them. At this point, the isolated population is considered to be a new species.

Examples of Wallace Definition

There are many examples of Wallace definition in the natural world. One well-known example is the Galapagos finches. The Galapagos finches are a group of closely related species that evolved from a single ancestor that colonized the Galapagos Islands.

The Galapagos finches have become so genetically different from each other that they are now considered to be separate species. This is because the finches live on different islands, and the islands are separated by wide stretches of ocean. The finches on each island have adapted to the unique environment of their island, and this has led to the evolution of different beak shapes and sizes.

Another example of Wallace definition is the Australian marsupials. The Australian marsupials are a group of mammals that evolved in isolation from the rest of the world. This isolation has led to the evolution of a unique group of mammals that are only found in Australia.

Importance of Wallace Definition

Wallace definition is an important concept in evolutionary biology. It helps to explain how new species can evolve and how the diversity of life on Earth has come about.