Question

Siblings do not resemble each other despite being born to the same parents. How and Why? What conclusion do we derive from the same?

Answer 1

Despite being born to the same parents, siblings do not resemble each other due to
(i) Chance separation of chromosomes during gamete formation.
(ii) Recombination of genes due to crossing over of chromosome segments at the tome of gametogenesis.
(iii) Chance coming together of parental chromosomes at the time of syngamy.
Differences between siblings are called variations. Variations are an important tool in the struggle for existence, competitive success, competitive exclusion, adjustments in family and society and our adaptability at various levels.