Question

Evolutionary species concept is based on
A)Distinct Lineage
B)Unitary evolutionary tendencies
C)Unitary evolutionary role
D)All of the above

Answer 1

Hint: Species are the group of individuals which share similar characters and are capable of interbreeding so as to produce fertile offspring. Evolutionary species concept was given by George Gaylord Simpson. This concept explains the evolution of species based on the concept of ancestors and descendants.

Complete answer:
Evolutionary species concept states that the species is a distinct lineage( ancestor-descendent) in which evolution has taken place separately from another species and possesses an independent role and tendencies. The differences include morphology, genetics, behaviour and ecology. It states that all the species have a certain diagnostic trait which distinguishes it from another. This theory assumes that the members or a particular species are reproductively isolated.

The lineage concept is better than the biological species concept which denies the concept of interbreeding among different species which is an important aspect of species cohesion. It better explains all the reproductive modes.

It better explains the colonial lineage which explains that the species are descended from common ancestors. It also solves the problem of intermittent hybridisation. It is an evolutionary time dimension concept.

Hence, the correct answer is option (D)

Note: The disadvantage of this concept is that it does not explain the ancestral trajectory that is whether the species have originated from a common ancestor. The other concepts of evolution are interbreeding concept, biological species concept, ecological species concept, phylogenetic concept. Biological species concept is the most accepted concept as it explains about interbreeding.