What is Mutation Meltdown?

According to Evolution Dismatled "A mutation is generally any error during the copying of DNA. So when babies are produced, mutations can creep into their genome. But how many? If we only count mutations that change a single genetic ‘letter’ (point mutations), there are an enormous 100 to 300 new mutations occurring in every person in every generation!^[1] So that means if your parents have no mutations, you have 100-300, your children will have 200-600, your grandchildren 300-900, and so on."

Then how long will it take for extinction?

"This mutational meltdown described above, also called genetic entropy, is at work in all multi-celled life.^[2] So this is a huge affair. Alex Williams has shown that the extinction of life would take only a few thousand years, assuming that 100 new mutations occur per person per generation and generation times are 20 years.^"

^"The actual data show that the overwhelming number of mutations are harmful (even if only slightly harmful), and that natural selection is useless most of the time. It cannot “see” most of the mutations in order to get rid of them. Far from being a viable mechanism for evolution, mutations sound the death knell for the evolutionary theory of common descent." - (Evolution Dismantled, n.d.)

References:

Evolution Dismantled. (n.d.). Evolution vs Mutation Meltdown and Genetic Entropy. Evolution Dismantled. Retrieved from http://evolutiondismantled.com/meltdown