The advantage is that we are average on all forms of terrain.
But we're not. We're useless on all terrain except dead flat.
Sure the dolphin can swim faster than a human but when have you heard of a dolphin that can walk on land.
Don't be ridiculous, we're talking about
terrestrial animals. If you're going to make this argument I'd point out that there's a large number of birds that can fly, swim, float, dive, and move about on land perfectly happily.
And contrary to your thinking humanities gait was actually proven to be the most efficient method of a bipedal gait compared to other forms that have been tried.
All I said was it's unstable, not inefficient. Our bipedal movement for walking is certainly pretty good, and for running it's not bad either, but the Red Kangaroo eats us alive as far as long distance bipedal gait goes, and it's vastly more stable. The arguments made for superior human long distance running tend to focus on the fact that we voluntarily run marathons, and animals don't, but I've always found this to be a rather enormously stupid argument. Most animals never do
anything for fun, and humans are renowned for doing things for fun that we're incredibly crap at - just look at the average human and sex. Further those humans that can do these sorts of things are the exception, not the norm - only 1% of people will ever complete a marathon in their lives and of that 1% only 10% will manage it in less than 4 hours. What's impressive about humans is that we're able to utilise our will power - a by product of our highly advanced brain - to push our body to perform in a way it isn't intended to perform. Mind over matter. That's why we're remarkable.
Anyway, as far as whether our bipedal gait is any good, I think you're missing my point. My point isn't necessarily that our method of bipedal locomotion is the worst form of bipedal locomotion (it has its advantages and disadvantages) but that bipedal locomotion of
any type is a flawed design (reinforced by how few animals rely on it as their primary mode of transport). (And for what it's worth the key factors contributing to our long distance running abilities are our hairlessness, sweat glands, and ability to breath through our mouth - having
nothing to do with being bipeds).
I'd posit that a hairless, sweating quadruped that could breath through its mouth would out perform humans in long distance running. Imagine a hairless, sweating, mouth-breathing kangaroo!
So wait your not throwing in all birds because of why now????? They do use two legs to walk you know.
Birds primarily transport themselves by flying, thus they are irrelevant. When I first raised this I did highlight flightless birds, but pointed at the the presence of wings on flightless birds tended to rather undermine the entire Intelligent Design thing, hence why I left them out.
And before anyone tries to argue that kangaroos hop and don't run, I'd then point out that
running is an inherently flawed method for long distance travel, so let's not get into those sorts of semantics.
