Actually we did have tails in early development of embryo. Vestigial arguments are basically arguments of ignorance just like junk DNA idea. Evolutionists loved to claim junk DNA was evidence against design yet the more we learn the more the junk DNA myth crumbles. Some of the so called junk DNA is important during development of the embryo while other only is express in certain cells. Going from a single cell into a man is very complex and we got so much more to learn exactly this take place.
Evolutionist first comes to the conclusion that something is vestigial or junk then tries their best to make the data fit their view. This is the exact same thing they accuse creationists of doing.
P.S it's just like "why do men have nipples?" Since our knowledge is so limited we don't know males have nipples due to efficiency which is a good thing. Evolutionist dogmatically claims it's because of evolution.
As an industrial designer myself, I can assure you that if I were to design all life as it is today (including humans) then I am afraid I would have been fired for incompetency after designing humans.
Any engineer who calls humans his greatest and most perfect design is not a good designer.
Just the fact that he designed the ingestion and breathing pipes to end up in one single pipe actually guarantees that thousands of people will choke to death every year. Dolphins do not have this handicap.
The mere fact that many animals have vision that far surpasses our own (including insects) or the fact that sharks have unlimited number of replacement teeth, or our sense of smell and hearing is abysmal compared to most animals just goes to show that this most perfect of designs called humans is in fact just like Windows ME® A TOTAL disaster and failure!
Also what kind of a designer would put the entertainment system in between two sewage systems