Question

Name the phenomenon that governs the following: -
i) Green beetles living in green bushes are not eaten by the crows.
ii) Number of blue beetles in green bushes increases, only because the red beetles living there were trampled by a herd of elephants.
iii) No ‘medium height plants’ are obtained in F1 generation, upon crossing pure tall and dwarf pea plants.
iv) Tails of mice were surgically removed for several generations; still mice had tails in the following generations.
v) A migrant beetle reproduces with the local population; as a result genes of migrant beetle enter the new population.

Answer 1

IN DETAIL

1. It can be both natural selection (that is survival of green beetles only while other coloured beetles couldn't stay alive because of predators) & adaptation (all the beetles adapted to change their colour into green for survival).

2. It's called genetic drift, where to maintain a balance in population a part of it becomes more prone to danger while other gain advantage and survive.

3. The dominance of T (tall genotype) over t (short genotype) results Tt genetic coded plants to be tall and not medium.

4. Acquired trait is the correct answer. Though this is not proved yet as the change occurs somatically and not in chromosomal level, these characteristics don't go to the next generation.

5. Gene flow is the correct answer as the mix of two genotypes occur from one place to other improvising the genetic orientation of the parent population

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IN SHORT

1. It can be natural selection and or adaptation

2. It is generic drift

3. Here, short genotype is dominated by tall genotype, but the plant should be tall and not of medium height.

4. The answer is acquired traits

5. The phenomenon occurring in this situation is Gene flow.

Answer 2

(i) Natural selection

(ii) Genetic drift

(iii) Law of Dominance

(iv) Acquired characters are not inherited.

(v) Gene flow