Why monkeys, as they allegedly evolved, lost their tails? A tail a tremendous advantage for a species.
Only if it is a species in a situation where a tail would actually be useful.
But, let's review what one has to believe to believe in theory of evolution:
1) You have to believe evolution occurred despite the fact that 99.9% of the physical evidence needed for it doesn't exist.
Depending on how you look at it, this is possibly technically correct - but that's becuse the 'physical evidence' needed is the various creatures that evolved, then went extinct as their descendants evolved into other creatures. They don't exist as they're extinct. The fossilized remains of the few individuals on each creatures population that actually got fossilized tend to support evolution, though.
2) You have to believe the first of all animal phylum evolved despite the fact they appear fully-formed the first time they appear in the fossil record after allegedly four billion years. The entire evolutionary fossil history of the first of these species does NOT exist.
If the kind of fossil evidence referred to here DID exist before then, that would actually be a bit of a problem for the current evolutionary model (as pointed out by the biologist J.B.S. Haldane, when he responded with 'rabbits in the Precambrian' when challenged to come up with something that could even hypothetically disprove evolution). According to that, organisms before then took various forms of colonies of bacteria, basically, which don't really leave that kind of fossil evidence behind. Other fossil evidence, however, does exist, dating from before then, that supports this model.
3) You have to believe soft tissue, which has been found in dinosaur bones could have survived 65 million years despite the fact that the best studies on fossilization (on Egyptian mummies) indicate that soft tissue can only survive 10,000 years.
Without knowing which studies being referred to here, I cannot state where the flaw is, precisely, but that conclusion is just plain wrong. Whilst very rare and unusual, it is entirely possible for minute traces of organic tissue to be preserved for considerably longer than 10,000 years.
4) You have to believe genetic mutations behaved differently in the past then they have been observed to today. There is one that provides proof one species can evolve into another.
When talking about 'microevolution' versus 'macroeveolution', the problem is actually the reverse of what's referred to here. As an analogy, evolution is like someone walking from New York City to Los Angeles. If they simply take one small step, then another, then another, and simply continued to do that, they'd eventually arrive in Los Angeles, though it would take them a very long time. What creationism says is that the walker would abruptly bang into an invisible wall when they get a certain distance from New York. Creationism has to explain what this wall is, where it comes from, and why it's there.
