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

Further reading

• W. Gabriel, M. Lynch, and R. Burger (1993). Muller's Ratchet and mutational meltdowns. Evolution 47:1744-1757.
• M. Lynch, R. Burger, D. Butcher, and W. Gabriel (1993). The mutational meltdown in asexual populations. J. Hered. 84:339-344.
• M. Lynch and W. Gabriel (1990). Mutation load and the survival of small populations. Evolution 44:1725-1737.