Question

What are the different types of species concepts?

Answer 1

In the process of taxonomic classification, species can be identified as a basic group of organisms that are genetically similar and are capable of producing fertile offspring. It is the most basic or rudimentary group to which organisms can be classified. A number of species that are similar come under the same Genus.

Complete answer:
There are six different types of species concepts. They are:
i) Evolutionary species concept: This concept was first described by Wiley in 1981 and considered species as populations of a single lineage that are ancestor dependent and are able to maintain their identity from a different lineage with respect to space and time.
ii) Biological species concept: This was the first concept to be defined among all the species concepts. And was put forth by Mayr, a zoologist in the 1940s. It defined species as a group of organisms that undergo interbreeding or have the potential to in-breed. And which are reproductively isolated from other such groups. The different characteristics of species as explained by Mayr are:
- Formation of a reproductive community: Where the members of a species search for reproductive partners among the same species.
- Forming an ecological unit: members of the community form a group and interact with each other and with the environment.
- Genetic unit: Within each group, there exists a valid as well as intercommunicating gene pool. And this helps in interbreeding between the members.
Phylogenetic species concept: It explains the similarities each member of a species shares with its ancestors. Or the resemblance to its lineage.
iii) Typological species concept: It explains how different groups of organisms exist and how there are limited or no relationships between each of them.
iv) Ecological species concept: Explains how when two similar species coexist in an ecosystem compete for food and other resources for survival since their basic requirements are the same.
v) Nominalistic species concept: This theory explains the concept of individuals. According to this concept, the theory of species is human-made and has no existence in the real scenario.

Note: Animals belonging to two different species can interbreed to produce offspring. But these offspring produced are infertile and are not able to produce any further offspring. An example of such a process is a Mule which is produced by breeding between a donkey and a horse.