For every one of our Human years, Dog's apparently have seven 'dog' years; I was wondering if there is actually any scientific basis behind this or if it is just an urban myth??

I saw a post today wherein the poster made a statement that we start dying from the moment we are born.  Surely this is not true.  I wouldn't think that biologically speaking the act of being born is anything special -- at that point we've been developing for 9 months or so and the only thing different is that we're breathing and eating on our own.

So, I'm interested in an actual scientific answer "when DO we begin to die"?  Looking forward to reading the replies.

I read an article in last week's New Scientist that said that if get two atomic clocks and raise one above the other, the higher one will go faster - speeding up time (albeit by a very small amount). Does this mean that by the time you die, your head is older than your feet? If so, by how much?

People with 'normal' memory can't remember much from before the age of 2, but is this the same for people with an eidetic memory? And does the eidetic memory start off fractured (as normal memory does) and evolve, or is it instant from the age it kicks in?

I noticed one of my head hairs looked a bit strange and removed it. From the root it was brown then towards the tip was grey.. I have never dyed my hair...how does this work?

Can bacteria die from "natural causes" i.e. do they age?

If they were not killed by anything or died by some sort of "accident", would they potentially live forever?

Relative to the hair on my head, my beard appears to be rapidly greying. In fact, it's very rare that a grey hair from my head shows up. However, my beard is going to "salt and pepper" quickly. Aside from the fact that there's less hair per square inch of skin on my face than my head, is there a specific reason for this?

Regardless of whether we travel at the speed of light or not, should our cells not biologically age and decay as per normal? Do we not have an internal biological clock that keeps ticking? Is Einstein proposing that our body will suffer less aging effects when travelling at the speed of light? Someone please help explain this....