Question

WHAT do you think is the most exciting breakthrough or discovery in ECOLOGY in the past 100 years and WHY do you think this discovery is so exciting? Note: the breakthrough must be somehow related to some field of ECOLOGY (such as population ecology, community ecology, ecosystem ecology, landscape ecology, behavioral ecology, physiological ecology, etc.), not just biology generally or environmental science (which is a different field than ecology!!). In addition, it should also be an ecological "discovery," not a technological "invention." I

WHO was/were the ecologist(s) who made these discoveries?

Answer 1

The Hardy-Weinberg Principle

Perhaps the most exciting breakthrough in Ecology and Evolution. The principle states that allele and genotype frequences stay constant in every generation in the absence of external evolutionary influences.The principle is named after G. H. Hardy and Wilhelm Weinberg who first proved it. This principle mathematically disproved the previously held belief that a dominant allele would automatically tend to increase in frequency in a population.

To explain the principle, Let there be a single locus with two alleles B and b with frequences f(B) = p and f(b) = q respectively. Under random mating the expected frequencies would be f(BB) = p² for homozygotes BB, f(bb) = q² for homozygotes bb and f(Bb) = 2pq for heterozygotes Bb.In the absence of selection mutation, migration and genetic drift, the allele frequencies between p and q are constant.

The principle can be generalised for two alleles, and polyploidy as well.

For organsims to validate the hardy-weinbergs principle, the following conditions should be fulfilled -

• organisms should be diploid
• only sexual reproduction occurs
• generations are nonoverlapping
• mating should be random
• population size is infinitely large
• allele frequencies are equal in the sexes
• there should be no migration, mutation or selection

This principle plays a major role in understanding specie dynamics in a given environment and how a population is expected to behave in the presence of different kinds of external factors. It makes possible the prediction of how a specie might evolve with the changing environment.