INBREEDING DEPRESSION Meaning and
Definition
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Inbreeding depression refers to a phenomenon that occurs when closely related individuals, such as offspring resulting from mating between close relatives, reproduce. It is a condition that is characterized by a decrease in the overall fitness or health of a population due to the accumulation of deleterious or harmful genetic traits. Inbreeding depression is primarily caused by the increased likelihood of inheriting recessive alleles or genes with negative effects.
When individuals within a population are closely related, the probability of sharing identical alleles or genes increases. This is particularly concerning when undesirable or damaging alleles are present. Inbreeding depression becomes more pronounced when these alleles are expressed in the offspring, leading to a variety of negative effects on their overall health and survival. These effects can include reduced fertility, higher rates of disease susceptibility, developmental abnormalities, lower growth rates, and diminished overall reproductive success.
The severity of inbreeding depression varies depending on factors such as the degree of relatedness between mating individuals, the size of the population, and the genetic diversity present within the population. Smaller populations or those with limited genetic variation are more susceptible to higher levels of inbreeding depression.
Inbreeding depression is an essential concept to consider in conservation biology and breeding programs, as it underscores the importance of maintaining genetic diversity and avoiding mating between closely related individuals. By doing so, the negative consequences associated with inbreeding depression can be minimized, ensuring the long-term health and survival of individuals and populations.
Etymology of INBREEDING DEPRESSION
The term "inbreeding depression" is composed of two parts: "inbreeding" and "depression".
- "Inbreeding" refers to the mating of individuals who are closely related by blood, typically within the same family or in a restricted genetic pool. It can lead to an increase in the frequency of homozygous alleles (having two identical copies of a gene) and a decrease in genetic diversity.
- "Depression" in this context refers to a reduction in fitness or viability within a population resulting from inbreeding. It describes the negative effects on physical, physiological, or reproductive traits caused by the inheritance of harmful recessive genes or the loss of beneficial alleles.
The word "inbreeding" has its origins in the Old English word "inn" meaning "in" or "within", and "breeding" meaning "to produce offspring".
