Industrial melanism is an example of:
► Industrial melanism is an adaptation where the moths living in industrial areas develop melanin pigments to match their body to the soot covered surroundings.
► In this case, moths with dark coloured will be selected by nature and hence they will be reproductively successful as compared to moths of light colour. Hence it is an example of protective colouration.
Geographic and reproductive isolations are most closely associated with:
► Geographical isolation is the physical separation of two populations by geographical barriers. This occurs through adaptive radiation and allopatric speciation.
► Reproductive isolation is the separation of two populations of the same species, preventing interbreeding and production of fertile offspring.
Industrial melanism was highlighted in:
The peppered moth Biston betularia is also a model of parallel evolution in the incidence of melanism in the British form (f. carbonaria) and the American form (f. swettaria) as they are indistinguishable in appearance. Genetic analysis indicates that both phenotypes are inherited as autosomal dominants.
An isolated population of humans with equal number of blue-eyed and brown-eyed individuals was decimated by an earthquake. Only a few brown-eyed remained to form the next generation. This kind of change in the gene pool is called
Population may sometimes be reduced to low numbers by predation, diseases, adverse period of climatic changes. Earthquakes, floods, etc. The few surviving individuals may constitute a random genetic sample of the original population. The resultant alterations and loss of genetic variability is known as bottleneck effect.
Hardy-Weinberg operates in the absence of:
The Hardy-Weinberg principle states that allele and genotype frequencies in a population will remain constant from generation to generation in the absence of other evolutionary influences. It operates in the absence of mutation, natural selection and recombination