Question

Which of the following evidence does not favour the Lamarckian concept of inheritance of acquired characters?
A. Absence of limbs in snakes
B. Melanization in peppered moth
C. Presence of webbed toes in aquatic birds
D. Lack of pigment in cave-dwelling animals

Answer 1

Hint: Lamarckian inheritance is defined as a notion that an organism can pass on to its offspring physical characteristics, that is acquired by parent organism during lifetime. This is also called inheritance of acquired characteristics.

Complete Answer:
The propositions of Lamarckism are:
- The parts of living organisms tend to increase in size continuously.
- The formation of new organs occurs in the body of an organism in response to needs.
- The organ which is used continuously tends to be highly developed and misuse results in degeneration.

Some of examples:
- The webbed foot is developed by aquatic birds by stretching the skin between toes.
- There is an absence of limbs in snakes.
- Giraffes have long necks.
- Changes acquired during the lifetime of an individual are inherited by its offspring.

Industrial melanism in the peppered moths was an early test of Charles Darwin natural selection. Loss of melanin pigment is found in many diverse cave dwelling animals.

So, the correct answer is B because melanism in the peppered moth belongs to natural selection.

Note: Industrial melanism is an evolutionary effect seen in several arthropods in which dark pigmentation that is melanism has evolved due to the environment which is affected by industrial pollution. Industrial melanism is studied in the evolution of peppered moth. The frequency of dark coloured moths has increased due to air pollution.