Final answer:
Inbreeding depression is the decline in biological fitness within a population due to the mating of closely related individuals, often affecting survival and reproductive traits. It leads to an increase in abnormalities and diseases due to harmful recessive alleles. Agriculture combats this through hybrid seeds, like in hybrid corn, which significantly improve yields.
Step-by-step explanation:
Inbreeding depression refers to the reduced biological fitness in a given population due to inbreeding, or the mating of closely related individuals. Traits affected by inbreeding depression are often those related to survival and reproduction. It occurs because such mating increases the chance of pairing harmful recessive alleles that can cause abnormalities and diseases. Inbreeding depression can lead to a decrease in offspring's reproductive ability and survival rates, impacting elements like heterozygosity and genetic diversity which are critical for a population's ability to adapt to environmental changes.
Within agricultural contexts, such as crop species with open breeding systems, inbreeding can result in substantial reductions in crop yield. This has been historically countered through the development of hybrid seed, where inbred lines are crossed to produce more vigorous offspring. A classic example can be seen in the development of hybrid corn, which dramatically increased corn yields.
It is crucial to avoid inbreeding in conservation genetics to maintain healthy and genetically diverse populations that are less susceptible to depression and other issues related to low genetic variability. The measurement of inbreeding coefficients, gene flow, and genetic diversity help in monitoring and managing inbreeding depression impacts on populations.