Biology

Vaccinations

The BBC 'Have Your Say' on potential compulsory vaccinations has the usual ill-informed rants, such as this from Astrid:

If more parents would actually do some research into the effects of vaccinations and their non-existing benefits there would be a lot more outrage against proposals like this. If anybody has problems due to a disease it is much more likely due to a weakened immune system and an unhealthy lifestyle (fast food etc), when is the government going to make that illegal?

I'd rather not get child benefits than poison my child with totally unnecessary and unsafe vaccines.

Whilst I'm with Astrid that compulsory vaccinations aren't the answer, and whilst I admit the possibility that some new vaccinations may do more harm than good, her reasons are ill-informed at best for the existing vaccines.

Why on earth would so much cash be spent on non-existing benefits? Why would they push it so much?

Compare the (now eradicated, except in labs) Smallpox with the vaccination for smallpox. Smallpox was a contagious disease which killed roughly 30% of those infected. The vaccine wiped it out.

The controversial MMR vaccine has been linked to Autism on anecdotal evidence. 'My child was vaccinated and then got autism' runs the argument. Well, correlation doesn't imply causation. How does that person know that the autism wouldn't have happened anyway? It manifests at about that age in many cases.

When people do a proper study, looking at the incidence of autism in those who have had the MMR against the incidence in those who haven't had it, there is no statistically significant difference.

Couple this with the now forgotten fact that measles is a particularly nasty disease, which used to be prevalent. The rate of complications occurring was low (at least in developed countries), but the rate of transmission is so high that it caused problems. Complications can include encephalitis (swelling in the brain) and corneal scarring. In the last 150 years, it has caused about 200million deaths.

I've had the MMR, and it might be tempting to think "sod 'em, I'm covered". The trouble with this attitude is whilst I'm not going to get measles (unless it mutates), once the incidence of vaccination in the population goes down an outbreak becomes more likely. An outbreak can totally overwhelm local medical services - and as a result has knock-on effects.

The trouble for people deciding about vaccinations is they have two options. Have the jab, or don't. They obsess about the risks of having it, and neglect the risks of not having the jab. It seems to be that people think: 'If I give the jab and there are complications, I'll never forgive myself - but if I don't give the jab and there is a disease then it's act of God'.

Ridiculous reasoning.

If you don't give the jabs and the child is exposed to complications surrounding measles (including brain damage and death), they're exposed to mumps (which can cause sterility), they're exposed to tetanus (which can occur if they're injured, not uncommon for kids)

Inaction is not making no choice. It is choosing to do nothing, and that has risks, just as taking the jab does.

Being the one person not vaccinated if everyone else is vaccinated is the best option - however, being a group of unvaccinated people is the worst option. It's the classic prisoner's dilemma. Being an iterated prisoner's dilemma, the best solution is vaccination. (In a one-off dilemma, non vaccination wins).

Yes, demand the scientific basis for a vaccine. Demand that it has passed clinical trials and doesn't cause more problems than it helps solve - but, Astrid, the vaccinations on offer at the doctors have done this. Look at it this way: The NHS would be spending a lot more money to help care for a sick child than it would to vaccinate, and at the end of the day, they'll do whatever is cheaper. In this case, it's in the interest of their bottom line to spend less and this coincides with your child being healthier.

It's win-win.

Additional: This whole 'debate' has many articles which are prime candidates for spEak You're bRanes!

Don't know much Biology?

In an excellent piece, Jerry Coyne laments the lack of Scientific literacy in our technological age.

Science simply doesn't deal with hypotheses about a guiding intelligence, or supernatural phenomena like miracles, because science is the search for rational explanations of natural phenomena. We don't reject the supernatural merely because we have an overweening philosophical commitment to materialism; we reject it because entertaining the supernatural has never helped us understand the natural world. Alchemy, faith healing, astrology, creationism, none of these perspectives has advanced our understanding of nature by one iota.

Scientific truths are facts agreed on by all observers using scientific methods. The formula for water is H2O, the Earth is 4.6 billion years old, and the speed of light is 186,000 miles per second. These are matters that can be verified empirically by any scientist, be she Muslim, Catholic, or Hindu.

The religious conviction that "man" is unique in ways that really matter is compelling in many ways, surely our language, art, music, and science itself are unique products of life on this planet, but holding our uniqueness to be a dogma immune to scientific analysis is an arrogant, and ultimately foolhardy, declaration of authority.

Multivitamins increase risk of Prostate Cancer

It's been shown that taking multivitamins in high doses increases the risk of prostate cancer by about a third, and the risk of a fatal cancer is doubled.

"The findings indicated the risk of advanced prostate cancer is 32% higher in men who take multivitamins more than once a day compared with those who do not take them at all."

"Risk of fatal prostate cancer was almost double. "

What about the risks to people who take the recommended dose?

Regional Cows

Like birds, it has been found that cows have regional accents. On the BBC news site they have recordings. Whilst I'm quite happy to go with mooing variations, I'm not terribly convinced that the cow accent should be in any way reminiscent of the human accent, as the Five Live snippet seems to suggest.

This is also discussed on language log.

(This is a case of something which has been 'spun' from 'it is possible' to 'it is true')

Flying Spaghetti Monster

I do like Wikipedia, it will occasionally throw up greatness such as the Flying Spaghetti Monster. This was created to highlight some of the poor arguments used by the proponents of intelligent design. Whilst the content is rather silly, the illustration does highlight the absurdity of the arguments. As an aside, one can have an absurd argument which leads to a correct conclusion, for example - this is an absurd argument that leads to a correct conclusion. Ignoring the occasional three legged dog for the moment - All dogs have four legs, Rover has four legs therefore Rover is a dog.

If you can't see what's wrong with this consider the equivalent argument: All dogs have four legs, my cat has four legs therefore my cat is a dog.

This equivalent argument highlights the absurdity in the original argument (even though the original argument yields a correct conclusion).

The flying spaghetti monster shows the problems in the arguments used in support of 'Intelligent Design' (aka Creationism). It doesn't mean that the conclusions are false - but the arguments are. Hence they have no place in science. (Note that one cannot infer anything from the previous sentence about my particular beliefs).

One touch which I particularly liked is the correlation between pirates and global warming.

The website of the Church of the Flying Spaghetti Monster is here

'Deadly' Bird Flu

It's really starting to bug me how nobody can talk of the H5N1 virus without adding a word like 'Deadly' or 'Lethal' in front of it.

Inevitably this causes people to worry and then calls go out for people to not panic, feeding the cycle.

Currently it is neither lethal or deadly. It really isn't. Since 2003 H5N1 has killed less than 100 people worldwide. Regular flu kills many more people each year, here are the figures for the USA. Last week, in the UK some 10000 people died from respiratory illnesses (though none reported as influenza).

Granted, should H5N1 mutate to be transmissable between humans then we have a problem - we're overdue a pandemic. Remember SARS? That was to be the next big pandemic.

Yes, it is true that flu viruses mutate. It is also true that these mutations can have disasterous consequences - however there is nothing to say that a particular virus will mutate. What is certain is that it will happen. Sometime.

We're currently on the lowest possible level of pandemic alert., admittedly, level 3 (out of 6 where 6 is pandemic) is the highest the alert has been in about 40 years.

Whilst we wait for that, let's not blow things up out of proportion. H5N1 is not a nice thing, if you're a duck.

It is not currently transmissable between humans - and so this does not a pandemic make. Regular flu is much more of a problem as of right now - but it's less newsworthy.

Yes, H5N1 should be monitored. Yes, we should be alert to the possibility of mutation, and act quickly if it does. However, let's not scaremonger... doing so will only lead to the 'Cry Wolf' syndrome.

Until it does mutate, let's just talk of H5N1 and not 'The Lethal H5N1 Virus', shall we?

Further Reading:

First Biology, now Physics...

Following the (ahem) thorough and robust discrediting of Evolution and the infinitely wiser Theory of Intelligent Design, the wise ones have now shown that the Physical ideas behind Gravity are lacking - and should be replaced by the theory of Intelligent Falling.

"Things fall not because they are acted upon by some gravitational force, but because a higher intelligence, 'God' if you will, is pushing them down,"

Later on the story goes on to give the reasonable point that

The ECFR, in conjunction with the Christian Coalition and other Christian conservative action groups, is calling for public-school curriculums to give equal time to the Intelligent Falling theory. They insist they are not asking that the theory of gravity be banned from schools, but only that students be offered both sides of the issue "so they can make an informed decision."

Tongue is now removed from the cheek where it had been lodged. Yes, the above story was a spoof.

The point I want to make is that ALL science should be taught as 'a work in progress'. Presenting things always as 'fact' is a disservice. For example, when discussing the solar system one can take a historical look at Ptolomym Tycho Brahe and so on.

Popper talked of science being 'falsifiable', i.e. that we can design tests, that a theory must be capable of being falsified. However that we could never prove a theory to be true, but simply fail to show that it is false. These are not the same thing.

By this token the intelligent design mob have a point - I cannot show that intelligent design is false.... but is it open to falsification? Evolution is, one possible falsification is for the creator to show up! HOWEVER, for intelligent design to be true there would have to be a whole load of assumptions made, such as:

I suppose one could argue for a 'designer' doing all that - it seems like she'd be rather busy though... and at times rather malicious.

There is another rule in science, that is that if you cannot design an experiment to differentiate between two predictive hypotheses, choose the simplest. This is called Occam's razor. The designer hypothesis has the problem of 'who designed the designer' - it simply shifts the question, but doesn't change it. Evolution has the problem of 'first reproducer' - but this is a problem of simpler order, see 'The Blind Watchmaker' by Dawkins.

If Popper's idea of falsifiability were all, then Ptolomy and Copernicus would have been on equal footing as far as Galileo was concerned - it's just that Copernicus' model was simpler... (okay, Galileo also had the moons of Jupiter to drop him a hint, but these could have been incorporated into a Ptolomaic model if one was willing to go through contortions). It wasn't until Newton that a mechanism was proposed for the motion of the planets, Occam's razor was Galileo's main guide.

Hint for Creationists: It helps if you understand what you're trying to refute. For example:

Natural selection is not evolution. This merely weeds out organisms and the information they contain; it doesn't generate new information. The creationist Edward Blyth discussed natural selection 25 years before Darwin, but recognized that it was a conservative, not a creative, force.

Mutations are not evolution. They are copying mistakes in the genes. No mutation is known to increase information content; every known mutation has either decreased information content or was informationally neutral. This applies even to the rare examples of beneficial mutations.

Natural Selection plus mutation IS evolution, the two seperately is not. Most mutations will be detrimental, this much is true. However where a mutation causes a greater success rate in producing viable offspring, it tends to be selected for. The key is viable offpsring.

Note that 'increasing information content' is not evolution - not is it a priori impossible! Indeed, the second law of thermodynamics relies upon it.

Yes, on the face of it one might think that selection only acts upon pre-existing variation - but this is not the case. Suppose one killed bacteria with penicillin. From time to time some survive, these will be the most resistant in the population (maybe the course of antibiotics was not completed). One might see this as simply looking at a variation which as already there. However the progeny will occasionally mutate and we get some extra resistance, and some with less resistance - surrounding this new higher resistance average. At the next exposure anything that is a bit weedy is killed off, and we get the strongest surviving. Where penicillin used to work pretty well, it often doesn't work now - this is because where people did not complete courses of antibiotics the 'strongest' bacteria survived, then mutated. Repeating this over many generations gives bacteria that can survive even the complete course.

Without mutations that are then selected, this looks feasible:

Natural selection: the drugs wipe out all the non-resistant germs, so the most resistant germs survive and multiply. This leads to a whole population that's resistant to antibiotics. This is not evolution because the resistance already existed in the population. Despite this, the PBS Evolution propaganda series used selection of pre-existing antibiotic resistance in tuberculosis germs as a major "proof". In fact, some bacteria revived from corpses frozen before the development of antibiotics have shown resistance.

Selection for resistant bacteria is a real danger when a patient fails to complete a prescribed course of antibiotics (60 days for Cipro)—i.e. stops taking the drug when the symptoms ease, which just means that most germs have been destroyed. The remnants require the final doses of antibiotic to finish them off, but if the treatment stops, they are free to multiply. This time the drug is far less effective, since the remnant population will tend to be the more resistant ones.

The reason that fails as an explanation is because, by it's own admission those bacteria that survive would have been killed. The key is that though these are the 'strong ones' their projeny will have variation, some weaker, some stronger. Applying an antibiotic from time to time knocks out the weaker end. This means at over time the progeny will be strong enough to resist even the full antibiotic course. That IS evolution

One can show that organisms change and adapt. It is possible to falsify claims to the contrary. As for there being a designer's hand? That's one for Occam's razor. Although one could argue not, as Occam's razor only applies to 'predictive theories', and intelligent design is not that. (Note, a predictive theory does not mean that predictions are always possible!)

Another hint for creationists: Evolution IS 'just a theory, but so is every other bit of science ever.... really it is. The way to discredit evolution is to find evidence which simply does not fit. Evolution can explain things like antibiotic resistant bacteria, for intelligent design to do the same you need to assume a malicious designer. Just as a scientist considers all the evidence, you must do the same too, I can recommend books like 'The Selfish Gene' and 'The Bllind Watchmaker'. Get later editions as these have appendices which answer the sorts of questions that you will have when you read. No - I don't intend to get drawn into a long debate on this one unless evidence and reason is at the core. Quoting a piece of scripture does not count as evidence.

Ebu Gogo

I've just seen a report on the BBC Television news about 'The Hobbits'. They said something along the lines of 'it shatters theories about human evolution'. Excuse me? How's that again? Given that the theory of human evolution doesn't preclude offshoots, this evidence is not contradictory, if nothing else it adds to the evidence base that humans are subject to evolutionary pressures - like other animals. We see evolution all around us all the time, most noticably in species with short lifetimes such as bacteria, the reason people find it difficult for humans is that, by neccesity, one human lifetime doesn't see much (any) change.

Whilst it does not change fundamental ideas of human evolution, what it does do is revise our expectations about brain size neccesary for tool use - but that is a whole different ball game.

Indeed, the most important result would be if we found some reasonably intelligent living specimins... I wonder how the fundamentalists would react to that? (Probably badly, and claiming that they were 'without soul' - but I hope I'm wrong).

The Hobbit

There have been reports today of a 'new' species of human, nicknamed 'Hobbits'. The fully grown specimin found was three feet tall, and there is evidence of tool use. The species had a common ancestor with Homo Sapiens in Homo Erectus, and evolved seperately in Indonesia. There is some possibility that the species, Homo Floresiensis, evolved elsewhere and arrived on the islands.

Intriguingly, there is local legend of small people called Ebu Gogo living in the forest within living memory. Would it not be fantastic if the species survived? It would bring a whole new outlook on our position in the natural world - especially if they had very Homo Sapiens-like characteristics.