Does life span actually matter to animals, and why do we all live for different periods of time?  Does a beetle's life feel quicker, or what?  Why has evolution made us like this?

I was studying anatomy in school but as a class we just could not get around the uselessness of the tailbone. Did we lose a tail? Is there a similar structure in other animals? Are there any other useless parts of the body?

I live in peace with the nettles in my garden… until one of them stings me. Then I obliterate the entire species (as far as I am capable). Why have the nettles not evolved a better (i.e. stingless) strategy? There are no large herbivores in my garden, so they are under no pressure to remain "armed".

The same can be said for thistles, brambles and all sorts of other, painful encounters.

I am wondering if there are statistics on the increase in prevalence of genetic diseases due to people living who otherwise would not. We are currently not fixing the genetic mutations that cause these problems but are treating the symptoms.

I am a firm believer that we are doing the right thing by helping these people but do we have a plan for the future?

How far are we off being able to safely administer germ line genetic therapy so that a person’s offspring will not be at risk of inheriting the disease?

I read somewhere recently that humans had all but finished evolving over the natural course of time. Whether that may be disputed or not, what I'm wondering is this: in some fifteen million years (which, according to David Attenborough's Life On Earth, is the amount of time it took us to make the transition) will primates evolve to be like us?

I have noticed, as others may have, that as a race humans have everything done for them; travel (cars, planes etc.), hunting (guns, breeding food etc.), and also there is no longer a need too compete for homes (we can simply build more). is there any need to evolve any further? have we reached our final stage in our long evolutionary chain? 

For a scuba diver, one of the best underwater sights is a rock face covered in brilliantly coloured jewel anemones (Corynactis viridis). They exist in many colours, and often vivid contrasting colours are found side by side. There are also subdued, semi-transparent variants.

Most species of wild animals have evolved to just one or a narrow range of colours, while flowers can have a range of vivid colours, presumably to attract a variety of insects.

As far as I know, the anemones aren't trying to attract their prey - it just arrives on the current. So why are they so vivid and so varied?

George Gall, Truro, Cornwall, UK

(Image: Kunstformen der Natur by Ernst Haeckel / Wikimedia Commons)