Question: Do experts agree about why we age?
About the article "Biology", section "Basic unresolved problems in biology".

Candidate passages:
When we see people, we recognise individuals, we make judgements about them, we draw conclusions about their age, their sex, their personality, their mood and their intentions.
And, deliberately or not, we send signals to others - through our expressions, the way we dress and the way we modify our bodies.
This issue of 'Big Picture' looks at this remarkable interplay - between the biology that sculpts our form and the culture that interprets, embellishes and adapts this form.
It asks what we mean by ‘normal’, what beauty is and how such concepts influence the way we live.
It looks at why we take the form we do and considers what we might look like in the future. 
  ""Our belief is that we have to hold up the standard of abstinence, and we do that in all of our teaching about sexuality by saying that sexual activity outside of marriage is wrong.
Now that's a very high bar to set and I understand that.
And I don't regret that – I subscribe to it and I teach it.
I understand why people find it difficult and disagree with it.
I understand why they do.
I don't agree with them... What I would say is that people who disagree with us can disagree without being disagreeable.""
On February 5, 2003, Colin Powell spoke to the United Nations Security Council:Since 1998, [Saddam's] efforts to reconstitute his nuclear program have been focused on acquiring the third and last component, sufficient fissile material to produce a nuclear explosion.
To make the fissile material, he needs to develop an ability to enrich uranium.
Saddam Hussein is determined to get his hands on a nuclear bomb.
He is so determined that he has made repeated covert attempts to acquire high-specification aluminum tubes from 11 different countries, even after inspections resumed.
These tubes are controlled by the Nuclear Suppliers Group precisely because they can be used as centrifuges for enriching uranium.
By now, just about everyone has heard of these tubes, and we all know that there are differences of opinion.
There is controversy about what these tubes are for.
Most U.S. experts think they are intended to serve as rotors in centrifuges used to enrich uranium.
Other experts, and the Iraqis themselves, argue that they are really to produce the rocket bodies for a conventional weapon, a multiple rocket launcher.
Let me tell you what is not controversial about these tubes.
First, all the experts who have analyzed the tubes in our possession agree that they can be adapted for centrifuge use.
Second, Iraq had no business buying them for any purpose.
They are banned for Iraq.
I am no expert on centrifuge tubes, but just as an old Army trooper, I can tell you a couple of things: First, it strikes me as quite odd that these tubes are manufactured to a tolerance that far exceeds U.S. requirements for comparable rockets.
Maybe Iraqis just manufacture their conventional weapons to a higher standard than we do, but I don't think so.
Second, we actually have examined tubes from several different batches that were seized clandestinely before they reached Baghdad.
What we notice in these different batches is a progression to higher and higher levels of specification, including, in the latest batch, an anodized coating on extremely smooth inner and outer surfaces.
Why would they continue refining the specifications, go to all that trouble for something that, if it were a rocket, would soon be blown into shrapnel when it went off? 
"Strictly Come Dancing" presenter Bruce Forsyth questioned the show allowing children to audition.
He said, "I don't think that's entertainment.
I don't think they should put children on that are too young.
If you're going to do that, have a separate show.
Have a children's show, "British Children Have Talent"."
Cowell responded to Forsyth, stating that: "someone, Mr Grumpy, said we shouldn't have children your age on the show", after the performance of dance troupe Youth Creation.
Jessie J joined the debate, declaring: "I cannot agree with kids having to go through three or four auditions when it's purely for ridicule.
I don't understand why it's legal, I think it's wrong". 
 "The Things We Do and Why We Do Them", Palgrave Macmillan, 2012.