Main Page | See live article | Alphabetical index Mutational meltdown refers to the process by which a small population accumulates deleterious mutations, which leads to loss of fitness and decline of the population size, which leads to further accumulation of deleterious mutations. A population experiencing mutational meltdown is trapped in a downward spiral and will go extinct eventually. See also Muller's ratchet. This article is from Wikipedia. All text is available under the terms of the GNU Free Documentation License.