Flightless birds: why are they found on islands?

Whilst on holiday (see previous post) I've been reading Jerry Coyne's excellent "Why Evolution is True".
Here's a tip: next time you encounter an advocate of "intelligent design" or, perish the thought, creationism, ask them if they've read his book  - or something comparable. Ask if they know about 'devolution' (my term ) which is the loss of function, with vestigial traits still visible - like that  otherwise inexplicable "floating"  pelvis and hind limb of the whale.  If they haven't, then refuse to enter into any discussion - probably futile in any case - until they have apprised themselves of the impressive marshalling of evidence in Coyne's book.

I should probably stop here - not presuming to be on anything like equal terms with someone who has spent his entire career researching the mechanisms of evolution (yes, the latter is possible, after a fashion, using his experimental model of fruit flies with their relatively short generation times). But I can't resist floating an idea that may or may not be codswallop. It concerns "flightless birds" - an example of that so-called 'devolution'.

The kiwi (NZ) - archetypal flightless bird

Here's Coyne's rationale:


"The long and the short of it is this: flight is metabolically expensive, using up a lot of energy that could otherwise be diverted to reproduction. If you're flying mainly to stay away from predators, but predators are often missing on islands, or if food is readily obtained on the ground, as it can be on islands (which often lack many trees), then why do you need fully functioning wings? In such a situation, birds with reduced wings would have a reproductive advantage, and natural selection could favor flightlessness. Also wings are large appendages that are easily injured. If they're unnecessary, you can avoid injury by reducing them. In both situations, selection would directly favor mutations that led to progressively smaller wings, resulting in an inability to fly."

Well, maybe, but wings confer such an extraordinary advantage over us terrestrial landlubbers that one has to seek an equally extraordinary reason why birds would divest themselves of such an advantage - even if  in thrall to random mutation and natural selection.

Here's my explanation - for what it's worth.

Suppose the first bird to land on an island had been blown way off course by strong winds, and had landed exhausted on its new home with abundant plant life and insects, but no snakes and other reptiles, or other predators- notably birds and mammals. Suppose too the bird had found a mate earlier, and was carrying eggs, duly laid in the new home.

The fledglings would have developed into fully-grown birds in due course. What then? Would they have stayed in their place of birth - or would they have been adventurous, and ranged further and further over the ocean in search of their more 'natural' habitat, ie that imprinted on inherited memory from mother?

Those that explored further afield might be fortunate and make landfall. Alternatively, and more probably,  they sadly would not make it, and would fall exhausted into the sea,  or hopefully perhaps turn back in time and return to their island home-sweet-home.

Over the millennia, natural selection would favour birds that were content to "stay put". Mutants that had progressive loss of flying ability would gradually predominate. Flight-capable birds would continue to suffer attrition, at least where the island was concerned. In the absence of predators, the flightless mutants would gradually displace the gypsy wanderers, provided there was sufficient food available at ground level - seeds, insects etc.

Maybe Mother Nature pioneered the joys of indolent vegetating, with old birds and/or their partners marooned on islands,  long before late middle-aged expatriate human beings arrived on the planet...

Sciencebod takes a late summer holiday

Yes, having spent most of the summer looking after a friend's house in Bratislava - complete with resident cats - it's time to have a touring holiday,  with no bowls to be re-charged morning, noon and night.

Where are we going?  Well, here's a clue. These structures are megalithic (which sounds technically savvy until you realise the literal meaning - "big stones"- which is hardly a giveaway.

We'll work in a visit to those" big stones", then travel north and hop across the straits to another more mountainous island. I've been sampling its beer, which recently appeared locally.

Chestnut flour is a major ingredient of the brew, we are told.  It's not bad at all,  with a well-defined malty presence, but maybe a tad too strong for my liking (6% alc).

If our various hotels all deliver on their wi- fi promises, I'll be able to keep an eye on the science news, and try to post a short report on anything that looks tasty. There are also a couple of posts in draft that could be fleshed out if rainy weather sets in - which is not impossible in mid-September, even in a location noted for its sunny climate. Will report back in a couple weeks - if not sooner.


Update  24th September

Am back from a fascinating 13 night recce of Sardinia and Corsica.  Visited the world-famous Su Nuraxi site at Barumini (see first piccy above) , about 50km north of Cagliari - which thanks to an officious and frankly sub-standard local guide was a mixed experience.

Here is the lady guide who not only insisted we join her group, despite her not speaking a word of English, but specifically prevented us from tagging along with the other guide whom we later heard using both English and Italian.

Reminder, young lady: Barumini is a UNESCO World Heritage site. To accept a question in English, and to reply in Italian is just downright inconsiderate, not to say perverse, especially when your colleague(?) was talking fluently in both languages.

Su Nuraxi? To give some idea of its age, it was abandoned  by its inhabitants, about whom we know next to nothing, in the 6th century BC. Prior to that, it had been occupied for millennia!

Random - and irreverent - thoughts on the British Science Festival

 John McCririck: missed his vocation as an SC (see below)?

Uh, uh.  It's that time of year again.  With the first chill nip of autumnal air, and the sight of new back-to-school satchels, or their modern-day equivalent, the UK press should now be going cold turkey on its silly season reporting.  But our esteemed MSM eases itself back into "business as usual" mode gently.  Temporary methadone maintenance is provided by the annual September shop-window for that charming if somewhat quirky organization - the British Association for the Advancement of Science.

Oops, I'm showing my age. It's abandoned that 19th century name,  conveying as it did an earnest desire to improve the scientific literacy of the muddled masses - and so cruelly satirized by Charles Dickens as "The Mudfog Society for the Advancement of Everything".

It now wishes to be known simply as the British Science Association.

I see that BBC correspondent  Sue Nelson is on the spot in Guildford for this year's jamboree - it's using the University of Surrey campus - and  is being suitably non-overawed by the occasion. Here's a delightful tongue-in-cheek equation she has "derived"  by which she rates  SC, the colourful "Science Communicators" she encounters:

H = the number of hand gestures

J = the brightness of a jacket

A = the number of times someone says "amazing"

F = the amount of facial hair

 
Well, we've had some quite memorable and sometimes colourful characters in front of our TV screens -  Sir Patrick Moore, Magnus Pyke,  James Burke. Maybe John McCririck should be drafted in, if only for his stratospheric SC rating (see graphic :-)

So what kind of science will be on offer this year?  Is science still capable of capturing the modern imagination?  Can we safely assume there will always be another "big idea" along soon, comparable to the DNA double helix,  genetic engineering, stem cells, plate tectonics, superstring theory etc etc. Or has science become so infected with quantum uncertainty that it is now dismissed as telling us more and more about less and less?  Will this year's Science Festival give us a taste of new insights, or is it a forlorn exercise in window-dressing, concealing an increasingly bare cupboard and shelves?

  (I choose my words carefully, having scanned the list of honorary members and sponsors, discovering names of people whom it would not be wise to offend, including an ex-employer who is now Something Big in Science Policy-Making.)

Religion seems to be flavour of the year at this year's Science Festival,  if the Telegraph Science page is reliable as a straw in the wind.

Well, it makes a change from  "Why future Moon colonists may keep bees" or similar  (OK, so I made that one up, but you get my drift).


Speaking of the Telegraph,  it seems to be on a religious kick at the moment. It's even spilled over onto its so-called Science Page. See the recent article by Christopher Howse:  "Do you Believe in Angels?"


 That "angels" feature incidentally provoked a quick riposte from your sciencebod   ;-)

"And to think this is the latest post in the DT's Science section! Is nothing sacred?"

One "getagrip" responded to this and similar sentiments with:

"The word angel occurs 194 times in the Bible.  My challenge to all those who have written sceptic comments is to go and read it for yourselves or just remain ignorant bigots."


Well, I guess that's  progress of sorts - the bible-quoters are now fighting fire with fire - quantitative data no less!

Incidentally: there are 64 occasions on which miracle(s) appears in the Bible. There's even a website for the benefit of the new breed of  Biblical number cruncher.  The most commonly used word,  not surprisingly, is "and"...


Update:  Scientist Lord May attacks BBC rejection of Planet Earth day


Thus reads the headline in the Times. It also needs to be read in conjunction with Lord May's somewhat  whimsical advocacy in today's Telegraph for a return to a God-fearing society (tongue-in-cheek methinks because he himself is described as a non-believer). Why? Because nothing less than religious commitment is likely to make people see sense on the need for urgent steps to prevent AGW.


Hmmm. There are some real characters in the upper echelons of the UK Government science establishment. Lord May, an ecologist, with wide-ranging interests and expertise in biodiversity etc,  was Chief Scientific advisor in the Blair government, and was President of the Royal Society for 5 years.  


My response to the Times:

"If I were religious, which I'm not, I'd be somewhat offended by the sight of a non-religious person (described elsewhere as an "atheist"), no matter how distinguished, telling me that my God was maybe a Good Thing after all, provided He is perceived as waving a big stick at climate change sceptics, bringing them to order.

I personally am slowly coming to accept at least some of the AGW arguments, but that's not because of politicians preaching about a so-called "scientific consensus" but in spite of them. Nothing is better guaranteed to turn off the enquiring mind than the claim that the time for debating is over, and that one must now obediently accept the nanny state's medicine like a good obedient citizen."

Fame at last!

 From today's New Scientist homepage

FAVOURITE COMMENT

Climate will cost much more than UN thinks

"Have you ever known anything to cost less than originally forecast? That would break an immutable law of grant-seeking." sciencebod

Here was my comment in full:


"Have you ever known anything to cost less than originally forecast?

That would break an immutable law of grant-seeking. Estimates are always pitched low initially, so as not to frighten off the fund-givers. They are then gradually and expensively racked up to take into account a host of hitherto unrecognized factors that no one could possibly have forseen, because their eyes were deliberately focused on the far horizon, and nothing so immediate and mundane as the nitty-gritty.

The maximum final/initial ratio is reckoned to be in the region of 3:1 for seasoned pros, who know how far they can push their luck. One notable exception are the organizers of the 2012 London Olympics, who are pushing the envelope, as they say, up into new unheard-of brass neck ratios. Hidden costs, like VAT for example, which no lobbyists, least of all at ministerial level, could possibly have forseen."

To global warming sceptics - other reasons for cutting fossil fuel consumption

 London photochemical smog - it begins with the burning of fossil fuels

Here's an article I would strongly recommend. It's written by Geoffrey Lean in today's Telegraph.
The strap under the headline  ("How's your carbon-footprint doing?") reads:

Cutting emissions of carbon dioxide makes sense even if you don’t believe in climate change.

And here is a quotable quote:

"Carbon dioxide emissions are turning the seas acid, and dooming the coral reefs, quite apart from their effect on global warming. Reducing fuel use would also cut other forms of pollution, such as the tiny particles, mainly from car exhausts, that EU research concludes kill some 30,000 Britons each year – shortening average life expectancy by six months – and the nitrogen dioxide which is increasingly implicated in the asthma epidemic that now afflicts one in seven British children... 

 ...   driving cars less reduces congestion and the building of new roads through the countryside. Walking and cycling are good for your health, as is eating less meat. Using water economically – and thus reducing the vast amounts of energy needed to pipe it around – helps tackle the water shortages threatening areas like the South East. Recycling paper saves trees. And so on."

Note regarding that nitrogen dioxide: it's a real insidious nasty. Why? Because the nitrogen does not come from the fuel, unlike, say, the sulphur in that other air pollutant - sulphur dioxide.  So there is no point in scientists seeking a low-nitrogen petrol or gas.  With the exception of coal,  fossil fuels have virtually no nitrogen to start with!

The nitrogen comes from the air. What happens is this: when our fossil fuels burn inside engine cylinders, gas boilers etc, the high temperature make some of the nitrogen  (normally considered chemically inert) to combine with oxygen to make nitric oxide, NO. That colourless gas then combines with more oxygen on cooling  to form nitrogen dioxide, NO2. That gas is no doubt responsible for most of the yellowish-brown colour of city smogs, and is highly damaging to our airways and lungs. NO2 is thought to be a major contributor to the increasing incidence of asthma attacks.

Here is a graphic showing the multiple sources of polluting nitrogen oxides in our air.

Source - same Camden link as above.

 So wherever you have fossil fuel being burned, you have toxic polluting nitrogen dioxide being formed. Sadly you can't have one without the other - no one's been able to find a way of uncoupling the two.

What a shame that nitrogen dioxide is not soot-coloured instead of being a light yellow-brown. Had it been so, one suspects that our burning of fossil-fuels would be much curtailed - voluntarily! 

Afterthought: Some of the pollution by nitrogen dioxide has admittedly been cut by the introduction of catalytic converters, now compulsory in new vehicle exhaust systems.  The platinum and other catalysts have been cleverly chosen to make nitrogen dioxide react with another dangerous pollutant -  carbon monoxide- to form non-injurious end-products:

nitrogen dioxide  & carbon monoxide react together on catalyst surface, and are converted to   nitrogen  & carbon dioxide

It helps, but there's still a hazard from NO2, which is not surprising since it's not just internal combustion engines that create it - see pie chart.

( Apol's btw for the divider lines. Not sure where they came from - some kind of formatting glitch)

 

Yes, it is theoretically possible to see into the past (to be taken with a pinch of salt)

 Safely home - and receiving calls?

It being a slow news day - at least where the science is concerned-  I was going to take a break. But I had an idea while shaving that I must share with you, dear readers.

They say it's impossible to travel back in time, right? I'm sure I don't need to remind you why (like what's stopping you from locating Hitler's grandfather,  pushing him under the wheels of a stage coach, thus preventing Hitler from being born? ).

But suppose I told you that it's theoretically possible to see what really happened in the past, say at Dallas, Texas in 1963, or to the Marie Celeste?  You'd say rubbish, would you not? Certainly I would have, up until a couple of hours ago.

Well think again.

Now you've heard of those distant exoplanets, right? They are outside our own solar system, orbiting their own stars. We know they are there - a few hundred have now been detected.  No, we can't see them directly, but they can be detected  by the small amount of light they block out when they transit their sun.

Suppose now there's an exoplanet called Zog, and that it is, let's say, 25 light years from Earth (our own Sun, by comparison, is 8.5 light minutes away, and the nearest star, Alpha Centauri, about 4.3 light years away).

Suppose the Zogians are far more advanced than we are, technologically, and have not only detected our presence, but have gone on to develop high-resolution video ( unlikely, but not theoretically impossible). Supposing Earth's history is being stored on Zogian video tape right now.  What it records right now is what took place on Earth 25 years ago - because that's how long it took the light to travel from Earth to Zog.

Now suppose we find a way of sending a radio message to Zog, saying "Hello neighbours. Please could you include us on your subscription list for Earth video footage?"  OK, so  it would take 25 years for Zog to  receive our message, and  - if they responded promptly-  another 25 years for the footage to get back to us. So Zog's most recent footage would show what was taking place on Earth 50 years ago,  albeit in Zogian "real time"!

For historians, it would be the equivalent of the "third umpire" in cricket - the video camera that is the final arbiter on what really happened... Now then, was there a second gunman, lurking behind that grassy knoll?

Who says artificial sweeteners don't help you lose weight?

 Is the love-affair over?

So who is saying that artificial sweeteners don’t help you lose weight?

Answer : Professor Soraya Shirazi-Beechey, who is a veterinary science researcher at the University of Liverpool.  She claims that "our bodies cannot distinguish between them and sugar."  So what's wrong about that, you might say?  We all know that artificial sweeteners - saccharine, aspartame etc - are no magic wands. But is the body totally fooled,  indeed traduced by them, even in the lower regions of the small intestine, as she claims?

Well, see the article by Chris Irvine in today’s Telegraph (Health Section) and judge for yourself. To say I read it with a growing sense of incredulity, indeed bafflement, would be a gross understatement. Little if any of it makes sense to me.

Let's  begin with the statement that “artificial sweeteners do nothing to help weight loss”. It does not appear to be a  finding of the Professor’s research. Indeed, from googling her other work, it would appear to be more by way of an article of faith.

Whilst I’m no expert on weight loss strategies – and am fighting a losing battle – that statement offends the most basic scientific principles. If somebody is on a dietary regime that just maintains body weight, and they then replace the sugar in that diet with artificial sweetener – then they are almost certain to lose weight, since their calorie intake is reduced. Now the cynics or defeatists may say differently, claiming, for example, that sweeteners increase one’s appetite for real sugars. But that does not permit the bald statement that artificial sweeteners do nothing to help weight loss. We all know, or should know, that any slimming aid has to be  part of a “calorie-controlled diet”.  We are constantly warned about that on the side of food packaging.

She then says that our bodies cannot distinguish between the sweeteners and sugar. Here’s where it starts to get scientifically a bit complicated, but bear with me, and see if you can follow the lady’s chain of reasoning.

We have at least two different sensor  locations for real sugars - sucrose, glucose etc - in our bodies. One is in the taste buds,  which detect “sweet”. These we know can be fooled, so that an artificial sweetener, with a chemical structure entirely different from real sugars, registers as “sweet”, making that cup of coffee more appealing to those of us with a sweet tooth.

But there's another place too -  down in the intestine -  where we have clever systems in the wall of the gut  concerned with selectively absorbing sugars into the blood stream. The important one where this post is concerned  deals with ordinary cane sugar ie “sucrose”, in our diet. There is an enzyme in the wall of the gut that recognizes and binds sucrose, and then cleaves it into two halves – glucose and fructose. There is then another system that recognizes and binds these sugars and then transports them across the wall of the bowel into the bloodstream. The glucose transporter works in conjunction with sodium uptake, and is called the sodium-dependent glucose transporter.

So where does the Professor’s research change our picture of this well-established digestive physiology?  She claims to have found yet another system in the bowel comparable to the one in our taste buds that recognizes “sweetness”.  In other words it  is activated not just by natural sugars but by artificial sweeteners. She herself has described that as “surprising”. Indeed, it is surprising. What’s a receptor for one’s perception of whether food is nice to eat or not doing way down in the bowel?  Down there one would expect molecules to be recognized purely by size, shape, chemical make-up – nothing so subjective as taste.

Now here’s where things start to get really bizarre. The prof' says that these new sweetener receptors are the reason why sweeteners don’t allow us to lose weight. She claims that the sweetener receptors fool our ordinary sugar-transporters into thinking there's an abundance of real sugar about, and send a signal to our sugar-transporters to work more efficiently. End-result – we absorb more glucose and other sugars from the diet than we normally would. Result: the sweeteners make our bodies more efficient at absorbing sugar calories, with the result that we fail to lose weight, and indeed are at risk of putting on weight

Hold on a minute. There’s a weak point in that argument – and that’s all it is – an argument – a far cry from doing  scientifically-controlled experiments.. It’s the assumption that sugar absorption from the gut is inefficient in normal individuals, and that sweeteners improve that efficiency.

Well, I personally know of no evidence that we are inefficient at absorbing sucrose. OK, it may not be 100% efficient – small amounts may reach the lower bowel where it would be fermented to hydrogen, short chain fatty acids etc. But if sucrose were just 95% absorbed,  with a "mere" 5% reaching the lower bowel, we would quickly know about it to our gross discomfiture, with bloating, wind, intestinal cramps – in other words all the symptoms suffered by those with the distressing and socially-embarrassing  "malabsorption syndromes".

Sorry, Professor , but your story does not make sense. To be honest, there seems to be just a little science, and a whole lot of conjecture. What’s more, it’s conjecture in an area in which consumers are already bombarded with a lot of conflicting information from scientists and health professionals. Someone has to act as watchdog. Who better than a retired biochemist/nutritionist with time on his hands? I would send a brief critique to the Telegraph, but there’s unfortunately no facility for doing so. But there is this ability now to attach comments and critiques to Google links. Tally ho!

PS   The Mail has opened a thread on this topic 


Update Sun 5th September. Who says that personal blogs are a waste of time, unless one is besieged daily by comments?

I've just been googlin', and find my humble observations as a "retired biochemist/nutritionist" have been picked up across the pond by an Atkins Diet/Low Carb forum.  Here's what "OregonRose" has to say:

"A few thoughts:

First, is this "real" research? There doesn't seem to be an actual paper or published findings associated with Shirazi-Beechey's alleged research; it's somehow "on display" at a Food Museum. That doesn't sound too awfully rigorous to me, although I might not be qualified to judge that. Also, in the articles I Googled up on her (Soraya Shirazi-Beechey + artificial sweeteners), I found lots of sound-bitey quotes from her but no mention of actual experiments and actual results. And there's this guy, a retired biochemist/nutritionist, who takes issue with what he labels her bald assertion, noting that there doesn't seem to be any experimental data to back up her claim:

http://colinb-sciencebuzz.blogspot....eners-dont.html

Second: As to the problem of where the "extra" absorbed glucose in a low-carb diet might come from--assuming for the sake of argument that her claim might have merit--what about glucose generated by the liver from protein? Supposing she's right, maybe somehow AS prods the liver to produce more?

And finally, the whole claim sounds weakly supported to me. Sure, I think avoiding AS is a good idea in general, along with any other frankenfoods, since we just don't know enough about them (heck, we know barely anything about our own physiology, and here we as a species are throwing hundreds of thousands of years of accumulated food wisdom away and eating who knows what...). Nevertheless, during my first year of LC, they helped assuage many a dessert craving, and I'm glad they were available."

I'd have left a comment, but not only is the site not open to those who are not registered, but I'm fundamentally opposed to the Atkins diet - not because it doesn't help lose weight - it almost certainly does - but because I consider it to be  misconceived - biochemically, physiologically and medically. The Atkins diet takes a huge liberty with one's cellular biochemistry - the subject of a forthcoming post.

Why is Moon dust sticky?

  This goddamned stuff gets everywhere!

I expect you have seen those close-up photographs of spacemen on the surface of the Moon. Have you noticed how they invariably have dust sticking not just to their boots, but higher up- often up to the knees in fact?  That dust is sticking to a vertical surface - in defiance of gravity - albeit weaker on the Moon than on Earth.

Well, there was an opportunity this morning on the New Scientist's website to mention that strange stickiness of Moon dust, and to speculate on what might cause it.

Afterthought: "sticky" is perhaps not the best adjective, since it may suggest "gooey". Maybe the title should have been : "Why does Moon dust stick to everything?"  If this were a scientific paper, which it's emphatically not, I guess one would be deploying terms like "adherent" etc. "Sticky" will do for now.

How come the mechanical engineers were able to steal a march on the Royal Society?

 The Royal Society HQ, London

The Institution of Mechanical Engineers, London

A few days ago the Institution of Mechanical Engineers was in the headlines - under photographs of highways lined with wind turbines and strange new "artificial trees".  The latter were poorly explained. In fact, even now, after diligent internet searches, I'm still not certain as to whether they are science fact or science fiction. More about the technological feasibility later.

For the moment, I'd simply say that I placed a comment on the Times, asking why a particular professional society with a mech' eng remit was hogging the headlines, given that solutions to global warming and climate change require an interdisciplinary approach.  I was careful to slip in a mention of the Royal Society in the list, feeling that it should be orchestrating the response from the UK's scientific, indeed engineering community too (since engineering solutions are only as good as the underpinning science).

Here's what I said...

"... one notes that these latest suggestions - which are by no means new - have come from the Institute of Mechanical Engineers. Might it not have been better if proposals for saving the planet had come from a broader-based consortium of professional societies, that would have included the Institutes of Biology, the Royal Institute of Chemistry, The Institute of Chemical Engineers, the Royal Society etc etc? The underlying chemistry/biology in today's press release is hardly impressive, and regrettably less-than-authoritative."

August 27, 2009 12:45 PM BST on UK-TimesOnline

Note the date.  Today, just four days later, the Royal Society has come out with  its own position paper, with proposals that look remarkably similar to those of the Institution of Mechanical Engineers.  Indeed, they ask for the same pump-priming Government support to the tune of of £10m. 

So, did the engineers jump the gun, one wonders, stealing the thunder of the senior service?   Did the latter wince on seeing its apparent inertia being pointed out by your humble blogger?  I guess we'll never know, but you have to admit that it's odd that two prestigious societies say basically the same thing within a few days of each other, with an apparent breach of the expected pecking order...

Newspaper sub-editors: bless them...

 Satellite photograph: Saharan dust, blowing westwards, carrying plant nutrients to the Amazon

There's an invited article in today's Telegraph by Steve Jones. His academic title is Professor of Genetics at University College London, but he's better known as a high profile author and TV presenter.  He is writing on Mother Nature's dust bowl phenomenon, scourge of farmers past and present, but tempered with the recognition that dust, stripped off land in one continent, can  provide nutrients thousands of miles away.This is a topic on which I blogged on the old Dreams and Daemons site.

Did you know that the nutrient-poor laterite soils of the Amazon basin are fed by dust blowing in from across the Atlantic - from the Sahara desert in fact, and from a relatively small part thereof (a  particular dried-up lake bed - the Bodélé depression- that is subject to ferocious sandstorms - or should that be dust storms?).

And what title has the Telegraph sub' used on the Home Page.  Wait for it: "View from the lab:  Beware of the dust".  The lab?  Well now, that's you pigeon-holed Professor Jones. Did they ask for a picture of you in a crisp white lab coat,  peering intently into a test-tube?

 Steve Jones

PS I see from Wiki we were both born the same year, but you already qualify for the State pension. This retired lab wallah still has a short while to wait.

Testing new Google comment facility on the Gareth Roberts diabetes story

Click to enlarge

I did a post yesterday on the amazing - some might say disturbing - report on the BBC's website about Gareth Roberts, the man who had  been on insulin injections most of his 32 years, and is now able to take pills instead - ones intended for what supposedly is an entirely  different type of diabetes.

Last night I googled *gareth edwards diabetes* to see what else was on the Web, and spotted not just a link to the BBC's story, but a facility to leave a comment. With my thoughts now hardening on Gareth's story, I immediately availed myself of that opportunity to say what I really think.  What you see above is a cropped image capture! The key words (final sentence) are  "He is now being presented as a medical miracle. NHS cockup more likely!"

It'll be interesting to see whether or not  this facility gives added audibility to one lone voice - moi- crying in that wilderness we call the blogosphere...

Scroll back 3 posts to see my own initial "take" on the Gareth Robert's story. Alternatively, click here.

One Diabetic: Diabetes and The Luckiest Man Alive!

One Diabetic: Diabetes and The Luckiest Man Alive!

"Am not sure how these links work, so I'll just insert the URL of my own post, on which I posted earlier today on the subject of Gareth Roberts. Medical miracle? NHS cockup more likely, if you ask me!"
Sciencebod

Confusing message? You betcha.  No, this IS NOT my main post on Gareth Roberts of diabetes fame. That's now two before this one.

So how on earth  did this one get here? Well, it's like this.

I had googled *gareth roberts diabetes* and found the link to the BBC's story. I then spotted a facility  I hadn't really noticed before, namely the ability to attach a comment to a Google entry, which I did so, asking  whether Gareth's liberation from daily insulin injections was really a medical miracle, or whether it was an NHS cockup. It'll be interestig to see if that added note  "makes waves" or not.

I then spotted another link lower down to the site of another diabetes patient, a genuine Type 1 patient this time,  and tried to leave a comment.

But  the "Leave a comment tab" was totally dead - why for heaven's sake?  Does he not want comments?  But there was a facility to link to one's own blog, and this new post  is the result. In other words, this post was generated completely automatically - by a robot-  without my being aware it would appear!  It's not what I'd intended, and I'm not over-enamoured with the result:  it's probably not really clear to you the reader how it came to be here, and could be confusing if you were looking for my main post.  But it may have its uses in future, now I now how it operates.

This blog-linking  facility is way of creating a shop window for someone else's post, which in this instance is the one at the top "One diabetic..." etc. But it's a tool I shall use with caution in future, since it has the potential to create confusion.

British plan to tackle asteroids

 One of these could really spoil your day

Have you seen that article on the BBC's website: "British plan to tackle asteroids"?

First, I have a confession to make. I know little or nothing about the detailed science - all I can offer is my gut feeling.

A couple of weeks ago I was reading the excellent Bill Bryson book : A Short History of Nearly Everything. He devoted a couple of pages to the threat from asteroids. It did not make for easy reading. It's reckoned that a relatively small asteroid, eg a kilometre or two in width - would be sufficient to extinguish life - or at any rate- most life  (certainly ourselves)  on Earth. What's more, its approach speed is so great that we would probably have only minutes - or seconds warning - of its approach.

So when the BBC article says that the threatening asteroid would have to be detected 15 years, no less, before its ETA,  time  in which for us Earthlings to mount our defences and  launch a so-called "tractor",  then it hardly inspires confidence.

But there's worse to come, at least where the science is concerned. The article says a space craft would be sent up that would park itself alongside  the asteroid.  It's mere presence would gradually make the asteroid veer off course due to the small amount of gravitational attraction between craft and asteroid.

Hold on a minute. The asteroid is vastly bigger than the craft.  The asteroid will pull the craft towards it with far greater force than vice-versa. The only way a small craft can act as a gravitational magnet would be if it had a propulsion unit that kept it at a constant distance, fighting the gravitational force. But that would surely require an input of energy - for 15 years or more. Is that why the article threw in a brief mention of solar power? Well, I say - that's one super Duracell battery.

I may be completely wrong, but my initial reactions are that this scheme is hare-brained - or maybe there's a lot more untried technology involved than the authors - or the BBC journalists-  are letting on. The BBC, to its credit,  inserts a little caveat - "No prototype have as yet been tested".   Pie in the sky?  Sci-fi hardware in outer space?

Tell me: are there any other kindred spirits out there who share my profound scepticism with what looks at first sight like silly season gimcrack "science".

Neonatal diabetes - a shocking case of correct diagnosis, but 32 years of wrong treatment

Gareth Roberts

You know how it is – when you tackle a subject which leads to exams. You learn all the different categories, which you store in your head in separate little compartments. Thus doctors and nutritionists are taught that there are two main forms of diabetes. There’s Type 1 diabetes, also called early-onset diabetes.  One day a child is fit and well, and next day it’s gravely ill, because its pancreas has stopped producing insulin, and blood sugar can no longer get into cells where it’s needed. There’s only one known treatment – daily insulin injections.

Then there’s the other form – Type 2 diabetes, also called middle-age onset diabetes, associated with obesity. The pancreas is still producing insulin, but not enough, or the tissues are  not responding to insulin.  For milder Type 2 diabetes, insulin injections are rarely necessary. Treatment is to correct overweight and faulty diet, supplemented if necessary by tablets of drugs like the sulphonylureas which stimulate insulin secretion from a flagging pancreas. Type 1 and Type 2 – and ne’er the twain shall meet, right?   Imagine the response of a James Robertson Justice type consultant if the young medic suggests treating a Type 1 (real or apparent) with sulphonylureas! "You NINCAMPOOP!!"

Yet that is what has apparently happened in the case of Gareth Roberts from Blackpool, reported in today’s BBC Health page  ("They have given me my life back") .

Gareth was born with diabetes, which was treated immediately with insulin injections.  For most of his life, he has been treated as if he had Type 1 diabetes. But he doesn’t. Type 1 diabetes usually develops in childhood, usually following an infection. It’s thought to be an auto-immune disease, in which the body starts attacking itself.

The good news for Gareth Roberts is that doctors at a West Country medical school decided to try him on sulphonylureas, for the “wrong” kind of diabetes, with near-miraculous results. The drugs control his diabetes. He no longer has to inject himself with insulin.

The bad news is that he’s spent most of his 32 years receiving 4 injections a day, because it was assumed that his form of diabetes was closer to Type 1 than Type 2, being apparently insulin-dependent, and that sulphonylureas are the wrong kind of treatment.

There is a moral here, methinks.  Medics – and their support scientists –  must always question the soundness or otherwise of their basic assumptions.  People who think out of the box should be given a fair hearing, and not immediately dismissed as nitpickers, awkward squad etc etc. 

Having said that, what a superb outcome it is for Gareth Roberts, to be freed from his daily regime. But spare a thought for the typical “Type 1” sufferers, for whom those daily injections are still needed.

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Viruses - did they evolve as a form of inter-species germ warfare?

 Swine flu virus

I know it's a crazy idea, but...

Have you ever wondered about viruses, and their place within the scheme of things? I mean to say - they are not living, and they are not dead. They are intermediate between the two. They have been called "incomplete organisms"?  Why? Because they are incapable of independent existence. They are simply infective DNA (or RNA)- enclosed within a protein coat. They are unable to reproduce themselves independently. The only way they can do so is by infecting a living cell - plant, animal, even bacterial - and hijacking the host's sophisticated biochemistry in order to make copies of themselves. They are parasites, in other words, and ones which have no other purpose except to make copies of themselves. They are the epitome of the "selfish gene".

It seems clear, then, that the sophisticated cell, capable of independent existence, evolved first, and the virus arrived later - as a spoiler. But why? What were the evolutionary pressures that drove the process, with such devastating consequences ( think pandemic flu, AIDS, hepatitis B, and a host of other viral diseases).

Viruses came up as a topic today on the New Scientist, and was an opportunity to fly a kite for an idea that's been incubating in this senescent brain of mine for some time.

Suppose viruses are not something radically different from, say, higher species, say pigs. Suppose they are pigs, or parts of pigs- ie  a maverick version thereof - that has been spawned to keep in place those who abuse pigs.

You can probably guess what I'm driving at. At some distant point in time, man started capturing pigs, and rearing them as food. But pigs had no way of knowing their fate as pork chops on a plate. But suppose that a mutant pig developed a malady, and began sneezing. And suppose the people keeping those pigs began inhaling droplets from the air, and the pig DNA and protein in those droplets  - prototype virus- invaded the mucous membranes of the farmers, weakening or killing them?  That would have given the farmed pigs a way of fighting back against their "predators", and the particular trait for infecting humans, being advantageous for surviival, would have been conserved by natural selection.

You see, pigs that sneezed and infected their owners would have survived longer, with an extra window of opportunity in which to mate and pass on their mutant genes. In time, the majority of pigs would have evolved these smart viruses,  ie shed-cells that can be sneezed out, that improve  longevity and mating prospects. In time, other species that are kept for food, like ducks etc, would also have evolved the same trick, and ducks, pigs etc then start exchanging infective DNA and protein, giving rise to flu pandemics. It's surely no coincidence that a lot of them originate in poorer, rural communities in which farmers live in close proximity with their animals, allowing opportunity for infective material to be transmitted.

Remember - all that's necessary for a virus to be infective is for it to be able to breach the protective cell membrane of its host, and then use its DNA to start running off  copies of itself within the host. The mere act of hijacking is sufficient to weaken - and sometimes kill-  the host cell.  But in time, the host cell develops an immune response, such that it is no longer killed outright by the virus.

So what I'm suggesting, in essence- is that viruses evolved as a form of germ warfare between one species and another. Farmed animals - pigs etc - may have been the first to strike back against us -  their oppressors!

My Projects (No.1): Is the world greening?

 Scattered acacia trees in Africa 

Anyone reading my intro top right might be forgiven for thinking this blog existed purely for sniping. Well, there's certainly a lot of misreporting (or at any rate, over-hasty ill-researched reporting) in the media. Somebody  has to correct the record. (I'll post at a later date on how effective or otherwise a private blog can be in that regard. For the moment, think just two words: Google returns).

Having trained as a scientist, and published in a number of areas, the itch to be doing one's own research never forsakes one. Whilst it cannot be the hands-on lab-based variety, there is still that amazing  research resource at one's finger tips - the internet search engine.

So from time to time, I will research topics that seem timely.

The first, as the title indicates, is whether or not there is evidence to back up suggestions that our planet is greening.   If so -and I appreciate that I could be accused of prejudging the issue-  then for what reasons? Is it due directly to increasing concentrations of carbon dioxide in the atmosphere? Or is it due to secondary changes in climate (temperature, rainfall  amount and distribution etc) that are associated with climate change - whether or not due to alleged AGW?

I'll add new information as I find it onto this blog - the primary source -  and  flag up this post from time to time to remind visitors that this is an ongoing project.

First step:  to google  "are trees growing faster". Well, one has to start somewhere!

The graphic? It was chosen having read about evidence for Sahara desert greening in the National Geographic News, and reports that trees are encroaching onto hitherto virgin areas above present treelines.


"Literature" search :

1. Trees are growing faster and could buy time to halt global warning    Telegraph 5 April 2009

Suspended term for tea poison man

Globules of mercury

I could scarcely believe my eyes when I read the above headline on the BBC site.  It's about a man who tried to poison his estranged wife by lacing her tea with mercury.

When you read the detail, it's clear that he used elemental mercury, ie the sort in thermometers.  Mercury is the only metal that is liquid at normal temperatures.  How do we know it was elemental mercury? See the reference to little "ball bearings" at the bottom of the tea cup.

Fortunately for the lady, her estranged husband was ignorant of chemical toxicology. Liquid mercury passes through the body largely unchanged, which would explain why her blood mercury levels were not raised, and why she appears - so they say- to have suffered no lasting ill effects - although she reportedly had symptoms of poisoning initially.

The real hazard with mercury comes from spillages. Mercury has an appreciable vapour pressure, and it's the vapour, when inhaled, which is highly toxic. Laboratories are required to have special decontamination kits to deal with mercury spills.  They used to contain elemental sulphur to which the miniature silvery globules stick. Whether they still do or not, I couldn't say.

Mercury salts and other compounds are also highly toxic, although one would probably be doubled up with pain very quickly if these were ingested.

OK, so the guy was ignorant, but the intent was still there. Why should his sentence have been so lenient?  The man tried to poison his wife - a despicable act - especially as it exploits intimacy and trust ("care for a cuppa, my dear?"). He wasn't trying to kill her, the court was told - but simply make her dependent.  He just wanted her back, under the same roof, grateful to him as a "carer" to a bed-ridden wife. Oh well, that's OK then...

Scientists finally image a single molecule (pentacene).

The most shared story on the BBC's excellent site right now is from the realms of chemistry - a subject that rarely gets a look-in these days.

It shows a remarkable "photograph" of a single molecule - obtained with a new gee-whizz imaging technique.

Here's the image (hope I'm not out-of-order here):

Pentacene molecule - in the flesh, so to speak

The molecule chosen for study is an aromatic hydrocarbon by the name of pentacene.  It's a relative of naphthalene (mothballs).  What's immediately clear from the piccy is that it's made from five fused six-carbon rings - benzene rings in fact. (Naphthalene by contrast has only two fused benzene rings).

The BBC's report draws attention to the fact that one can even see the bonds to hydrogen at the periphery of the molecule. However, that won't mean a lot to non-specialist readers if they are not familiar with pentacene's chemical structure.

Ay, but there's the rub - there are different ways of representing chemical molecules, depending on precisely which aspects one wishes to highlight.  A quick look at Google images will show what I mean:

Here's the most "realistic" model, so-called space-filling, in which the carbon atoms (black) and the hydrogen atoms(white) are shown in their correct relative sizes. The atoms merge with each other to represent strong chemical bonds. But the fused-ring aspect is now scarcely visible, the "hole' in the centre of each benzene ring being reduced to a mere white spot due to "crowding" of carbon atoms.

The conventional chemical shorthand strips out all non-essential detail, including the hydrogen atoms, and attempts to show the chemical bonding within the rings, as an alternation of single and double bonds (wrong, as it happens).

But that's another story: suffice it to say that chemists know it's wrong...

It took a bit of searching, but here's the representation that best complements, in my view, the BBC's image:

Ignore the second small molecule that hovers above pentacene. This structure shows clearly the five fused rings, and the hydrogen atoms. It is the bonds to the hydrogens at the two opposite ends of the molecule that are visible as bright areas in the BBC image. Don't ask me why the other C-H bonds are not easily visible.

So-called "synthetic trees" employ discredited mickey mouse chemistry!

 Both the BBC and the Times use this picture.  

The synthetic/artificial trees are the fly-swat shaped objects, not to be confused with wind turbines.  The BBC's caption reads "Artificial trees could be used in areas where carbon emissions are high".  The BBC's caption writer seems a little confused, inasmuch as CO2 "pollution" is a global, not a local problem.  He or she seems to be confusing it with vehicle pollutants like SO2, NOx, unburned hydrocarbons etc which are an immediate health hazard (asthma-inducing etc) as distinct from global-warming greenhouse gases.

There are reports right now on the BBC, in The Times, and no doubt elsewhere of so-called "synthetic trees" (aka artificial trees) that will help save the planet.

Your ever alert and  responsive critic of pop science has just  dashed off  the following and sent off to the Times:


"Sorry, but the technology for these synthetic trees, reported in 2003, has been totally discredited:

http://news.bbc.co.uk/2/hi/science/nature/2784227.stm

It uses plain old limewater* to sequester CO2. Where does the lime come from? It comes from roasting chalk or limestone at high temperature, which not only requires a lot of energy, but puts CO2 into the atmosphere.

1. calcium carbonate (+ heat) -> calcium oxide  + CO2 (gas)

2. Calcium oxide + water  ->  calcium hydroxide  (+ heat)

3. Calcium hydroxide + carbon dioxide  ->  calcium carbonate (regenerated!) + water

In other words the whole process, at least as originally described, is entirely self-defeating from the point of view of carbon sequestration. It's simply an expensive way of moving chalk or limestone from a hillside to a so-called synthetic tree by the roadside.

*an aqueous solution of calcium hydroxide"


The Telegraph is now running the same story, again with the same piccy, but unfortunately provides no Comment facility.

From the archives: here is a link to a BBC item on "synthetic trees" as long ago as 2003 which explained why the chemistry was a non-starter.
More later.

Latest breakthrough cannot eliminate all forms of cancer and diabetes

 

Cell mitochondria - highly enlarged - with their own DNA - able in some cases to transmit disease

Hereditary diseases, including cancer and diabetes, could be eradicated before birth, scream the headlines.
It hinges on new techniques for fixing faulty DNA.But not just any old DNA.

How can cancer and diabetes be prevented, given that those diseases, while having a genetic component, are not simple inborn errors of metabolism, but multifactorial - influenced by environment as well as genetics?

One has to read quite deep into the article to see the reasons for the apparent contradiction.

It's to do with mitochondria - those sausage-shaped subcellular organelles of which the typical human cell has a thousand or two (see graphic). Mitochondria play a key role in supplying the cell with energy, by providing a package of enzymes and electron-carriers that convert the energy of foodstuffs to ATP - the universal energy currency of living cells-  using molecular oxygen to release energy.

Remarkably, mitochondria have their own DNA. It's only a tiny proportion of the cell's total DNA, but certain diseases are due to defective mitochondrial DNA, as distinct from the predominant DNA in the cell's nucleus. The new technique prevents faulty mitochondria, with  defective DNA, passing on their defect to a fertilized human embryo, basically by transplanting the nucleus with its "good" DNA, leaving the bad mitochondrial DNA behind, and substituting "good" mitochondrial DNA.

So the technique only works for those variants of cancer and diabetes that are due to defective mitochondrial DNA.  Headlines that suggest that all cancer, or all diabetes, can be eliminated, are clearly misleading.

How come mitochondria have their own DNA? There is now an impressive amount of evidence that mitochondria are ancient bacteria that were somehow engulfed in early cells, and not only managed to survive, but set up a productive partnership. The host cell protected the bacteria, and the latter returned the favour by providing a highly efficient means of oxidising foodstuffs. Prior to the so-called endosymbiotic partnership, the host cells had to rely on glycolysis - the biochemistry of anaerobic fermentation in, for example, brewing and yogurt production, or anaerobic muscle metabolism, which provides a little energy without oxygen, which is not only far less efficient than aerobic metabolism, but generates potentially toxic endproducts (alcohol, lactic acid etc). The end-product of aerobic metabolism is gaseous CO2 - non-toxic because it is easily got rid of.

One curious feature of mitochondria is that is only the mother's mitochondrial DNA that is passed on to offspring.  Male gametes (spermatozoa) have mitochondria, but they are selectively destroyed in the ovum at fertilization. Mitochondrial DNA has proved of great utility in tracing human lineage back to one original  female ("Eve") in Africa, by avoiding the complication of all that invasive male DNA!


Further reading:  New Scientist article

  The Times