Nicotiana sylvestris flowers only during long days and N. tobacum flowers only during short days. If raised in the laboratory under different photoperiods, they can be induced to flower at the same time and can be cross fertilized to produce self-fertile offspring. What is the best reason for considering N. sylvestris and N.tobacum to be separate species?
They are physiologically distinct.
They are morphologically distinct.
They cannot interbreed in nature.
They are reproductively distinct.
Correct answer: (c)
Solution: The term species evolves from word specific means only those group of plants or animals come under one species which can interbreed and produce fertile offsprings naturally. N. tobacum and N. sylvestris cannot produce flowers naturally have different photoperiods, hence they cannot belong to the same species. Thus the correct answer is 'They can not interbreed in nature.'