For creationists the human tail is the result of a mutation and not “the recurrence of a formerly expressed allele” - as Faith put it - because that would be evidence for a shared ancestor of humans and great apes.
There is no musculature, nerve endings, or ligaments attached to these anamolies. All it is either a protuberant coccyx or distended skin, not a tail. Aside from which, if humans developed atavisms that are not normally expressed alleles, one might expect to see traits that are more current to the evolutionary timescale. What I mean to say is that if humans are indeed primates and we trace our lineage back to primates with tails, we are taling about hundreds of millions of years in between. Why wouldn't excessive body hair be a more prominent atavism than tails when there has been a hundreds of millions of years of disparity in between? It seems much more reasonable to recognize that these are deformities just like any other deformity, not tails.
For one this implies that benefical mutations should be quite common. Only in this century there are several documented cases where humans where born with a moveable tail containing connective tissue, nerves, blood vessels and muscles. In three cases tails containing vertebrae have been reported.
I've yet to hear of any cases where they were able to move their 'tails'. If you have any links to support the claim I would definitely like to peruse them. But even the event that some people were born with musculature and nerves in their distended coccyx, how would this be an example of beneficial mutation? If these people were born with opposable tails and could leap from tree to tree from their tails, I would certainly concede. But as of now its been reported as a discomfort when people sit down, in which case, I hardly see how it could be deemed beneficial.
Edited by nemesis_juggernaut, : typo
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