Question

Which of the following helps in species identification based on biological species concept?
A. Morphological distinctiveness
B. Behavioral distinctiveness
C. Physiological distinctiveness
D. Geographical isolation
E. Reproductive isolation

Answer 1

Hint: A species is characterised by the definition of biological species as representatives of populations that currently or theoretically interbreed in nature, not according to appearance similarity. While appearance is helpful in species identification, it does not identify species.

Complete Answer:
- In biology, species are classified as related organisms which share similar characteristics and are capable of interbreeding. In biology and related fields of research, this biological species definition is commonly used. There are more than 20 other distinct species definitions, however.
- A biological species is a group of individuals (panmixia) that can breed together. They do not breed with other races, however. In other terms, the group is separated from other groups reproductively. The terms 'reproductively isolated' are the main words of the concept of biological organisms.
- A new species forms when an established species divides, according to Ernst Mayr. Moritz Wagner proposed a similar concept in the 19th century.
- The role of reproductive isolation in the development of new species was identified by Dobzhansky. When a population lives in two different locations, mating between groups is limited or prevented by geographical isolation.
- Each community develops characteristics that make the breeding function less well between them. Eventually, each group becomes a 'healthy' biological species, and even though they are together, the two species do not reproduce with each other.
- The key explanation for classifying living things is biological organisms, but it is not easy to apply it in reality. The following are strong instances of this:
- As clear proof of separate species, including Dobzhansky's own observations of Drosophila sibling species, no lack of cross-mating, sterility or inviability was ever taken on its own.
- The definition of biological species has little impact on asexual organisms and, in its application to other organisms, has serious limitations.'

The correct answer is option (E)Reproductive isolation.

Note: Among many other things, the ideas of Ernst Mayr had immense significance for the creation and acceptance of the modern definition of the metapopulation lineage of organisms, and they continue to provide the basis for developments in the theoretical concept of organisms and its practical application.