Question

Mule is a hybrid. Which of the following statements is correct?
A. Mule is not a species
B. Mule is a new species
C. Horse and ass are two populations
D. Mule represents a common ancestor of the horse and ass

Answer 1

Hint: Hybrid is an offspring that results from the crossing of qualities of two organisms belonging to different breeds, species, genera, etc. by a means of sexual reproduction.

Complete answer:
 Interspecific hybridization means cross-breeding between two species which are from within the same genus. Mule is an example of interspecific hybridization; mule is an offspring of a male donkey and a female horse. The offspring of such breeding show characteristics of both the parents but they are often sterile (i.e. incapable of producing offspring) restricting gene flow (or genetic flow refers to the transfer of genetic material from one population to another) between the species. Mules possess ‘hybrid vigour’ which means the tendency of a cross-breed offspring to show characteristics or qualities such as size, growth rate, etc. which are superior to that of their parents. Mules can either be male or female but can't reproduce due to their odd number of chromosomes i.e.( from the horse and from donkey).
Mule is not considered as a species because the species is termed as a group of organisms which are capable of gene exchange or interbreeding and produce viable or fertile offspring. But mules are sterile which cannot produce their babies that is why they are not considered a new species.

Hence, the correct answer is option (A).

Note: Mules are referred to as ‘beasts of burden’ i.e. an animal that is used by humans for transporting materials. Skin of mules is thick which makes them resistant to heat and rain.