Thursday 1 April 2010

Blown away: some weird and wonderful animal defence mechanisms

At a time when environmentalists are calling for farmers to swap cattle for non-ruminant species such as kangaroos in an effort to stem bovine methane emission, a recent report by a leading Argentinean palaeontologist reminds me of Karl Marx's popular axiom "History repeats itself first as tragedy, second as farce".

The report's theme concerns animal defensive mechanisms, a classic example of truth being infinitely stranger than fiction. Consider for instance the bombardier beetle, an innocuous enough looking insect that when endangered can squirt a boiling liquid from its rear abdomen. Okay, that's only mildly weird. Well what about the several species of frogs and newts that when threatened extrude internal claws or spines by puncturing their own skin? Or the Asian carpenter ants whose soldiers literally self-destruct in the defence of their colony, in the process spraying a sticky poison over their attackers? Surely if anyone needed a good argument against Creationism then this panoply of the bizarre would suit admirably, since it postulates an equally bizarre, not to say warped, sense of humour on behalf of a Creator.

But the news from Argentina may well outshine (if that is the right word) all of the above, not least from the sheer scale of the animals involved. The main players are those undisputed giants of the dinosaur world, the South American titanosauria sauropods of the mid- to late-Cretaceous. Partial remains found over the past twenty years imply species such as Argentinosaurus may have reached lengths of 40 metres, thereby exceeding their better-known Jurassic relatives such as Diplodocus by around 20 per cent.

In 2002 Fernando Calvo, Professor of Natural Sciences at La Salta University in Argentina, became intrigued by sauropod growth patterns and nutrition. Although coprolites (fossilised poo) have not been found for any species of Argentinean titanosaur, the study of microscopic phytoliths, silicified plant fragments, suggest these animals enjoyed a broad plant diet. The notion that Mesozoic vegetation consisted primarily of conifers, cycads, horsetails and ferns has been overturned by recent discoveries of palms and even tall, primitive grasses. Since modern grazers such as cattle can survive solely on such unpromising material, how about titanosaurs?

Calvo and his team began a study to go where no scientists had gone before and assess the potential digestive systems of Argentinosaurus and its relatives. One of the luxuries of an enormous bulk is being able to subsist on nutritionally-poor foodstuffs, a case of sheer quantity over quality. The La Salta group hypothesised that their native sauropods were amongst the most efficient of digesters just because of their size: by the time plant material had worked its way through such a large digestive tract most of the nutrients would be absorbed, no doubt aided by gastroliths, literally stomach stones deliberately swallowed to help churn the material.

The preliminary report was published in March last year and quickly became notorious in palaeontological circles. For there was no delicate way of describing the findings: the titanosaurs would easily top the Guinness Book of Records' list of “World's Greatest Farters”. Whilst sauropods did not have the multiple stomach arrangements of modern ruminants the hypothesis was clear: titanosaur herds would have been surrounded by an omnipresent cloud of methane.

For Calvo, the next step came several months later when a tip-off from a farmer in Chubut led to an astonishing series of finds. The site, whose exact location remains secret, revealed the semi-articulated fragments from a tight-knit group of three predatory Giganotosaurus and approximately 15 per cent of the skeleton of a single, adult Argentinosaurus. Team member Jose Chiappe led the extraction work on the latter colossus and postulated that it had died slowly, perhaps due to blood loss following an attack.

What were far more intriguing were the positions of the attackers: all three had a slumped, head-down attitude, implying sudden collapse and virtually instantaneous death. Calvo found himself asking the obvious: how could they have died? Whereas a Diplodocus tail was well-formed for use as a whip, it was a much more gracile animal than its Cretaceous counterparts. The larger bulk of Argentinosaurus didn't bode well for a fast reaction: by the time a titanosaur had noticed the approach of a Giganotosaurus it would have had precious few seconds to position its tail for a whiplash response. Then Chiappe remembered an Early Cretaceous site in Liaoning Province, China, where animals had died of suffocation due to volcanic gases.

The resemblance in the post-mortem postures of the Giganotosaurus led to an incredible but as yet unpublished hypothesis: if correctly positioned, a frightened titanosaur could have defended itself by the simple expedient of raising its tail and expelling gaseous waste directly into the conveniently-placed head of an oncoming predator. An initial calculation based on scaling up from modern animals suggested an adult titanosaur could have produced about one tonne of methane per week. Computer simulations suggest a sustained five-second burst at close range would have K-O'd an eight-ton Giganotosaurus, and with a brain barely half that of Tyrannosaurus, it's unlikely the predators had the wherewithal to avoid their fate. If only the late Michael Crichton had known this, perhaps he would have written a scene involving an ignominious demise at the rear end of a sauropod for some of the characters in Jurassic Park (Jurassic Fart, anyone?) Or since this occurred in the Cretaceous, in the name of scientific accuracy perhaps that should that be Gone with the Wind?

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Saturday 20 March 2010

Come all ye faithful: do faith schools threaten British science education?

With the announcement of a New Life Academy in Hull opening later this year the debate over religious education in Britain has become more intense than ever before. Of course we need to take Richard Dawkins' rhetoric with a pinch of salt, but has the current administration allowed or even provided financial support for fundamentalist organisations to infiltrate the British education system at the expense of science and rational thought?

The Hull Academy will follow the Accelerated Christian Education curriculum that amongst other tenets supports the literal truth of the Bible. So how likely is it that the UK will take on aspects of the American Bible Belt, with critical thinking and enquiry subservient to dogma and absolute belief? One of the main criticisms of the ACE system is its reliance on learning by rote, yet at least in their pre-teens, children are shown to benefit from such a system. It appears to do little to quench their thirst for exploration and discovery, which if anything is largely stamped out by an exam-obsessed education system. If all learning is given via rote there is an obvious problem, but in the vast majority of British faith schools this does not seem to be the case.

Alongside the four Emmanuel Schools Foundation academies, the NLA Academy is an easy target for those fearing religious extremism. But outside of Hollywood, the real world is rarely so easy to divide into good and bad. Not only are the ESF schools open to all faiths but an Ofsted inspection failed to support the allegations of creation science being taught. Even if these faculties were heading towards US-style fundamentalism, linking their techniques to all faith schools would be akin to arguing that the majority of British Jewish children attend the Yiddish-speaking private schools in North London's Stamford Hill orthodox community. Parents who are desperate to indoctrinate their children will take a do-it-yourself approach if they cannot find a school to deliver their requirements.

Many senior religious figures of various faiths, including the Archbishop of Canterbury Dr Rowan Williams, have stated that they do not want creationism taught in schools. If there is any stereotyping in this subject, it is here: most fundamentalists concentrate solely on evolutionary theories, natural selection and its implicit linking of mankind to other animals, rather than any other branch of science. Although the age of the Earth (and therefore the universe in general), as well as the sun-centred solar system, is sometimes denied for its disagreement with the Bible and the Koran, there are few extremists prepared to oppose other cornerstones of modern science. Clearly, would-be chemists should feel safe, potential geo- and astrophysicists less so, and those considering a career in evolutionary biology should not move to the American Midwest (or even Hull!)

More seriously, what of more subtle approaches by the mainstream denominations? A 2004 New Statesman article maligned an Anglican school in Canterbury for its attempts to inculcate infants with religious sensibilities via techniques that sounded more like a New Age cult than the Jesuit approach, but since then there has been little in the way of comparable stories. Whether senior figures in the Church of England see faith schools as a way of replenishing their ever-diminishing flock is unknown, but there is no solid evidence for such a master plan. Britain has a long and let's face it, fairly proud history of ordained ministers who have dabbled in the sciences, although few who could be compared with the Augustinian monk Gregor Mendel, the father of modern genetics. Although T.H.Huxley (A.K.A. Darwin's bulldog) railed against the ordained amateurs, his main bone of contention concerned Anglican privilege: comfortable sinecures allowing vicars to delve in the sciences whilst the lower social orders including Huxley had to fight tooth and claw to establish a paid profession.

There are many examples of religiously devout scientists who can be used to diffuse the caricatured 'us and them' mentality, perhaps the best-known current British example being particle physicist the Reverend John Polkinghorne. Organisations such as the International Society for Science and Religion, and the Society of Ordained Scientists, both of which claim Polkinghorne as a member, are against intelligent design from both a faith and science perspective. Whilst the hardline atheists might deem these groups as intending to both have their wafer and eat it, there are clearly a wide range of attitudes in support of current scientific theories at the expense of a literal belief in religious texts. But then don't most Christians today express a level of belief as varied as the rituals of the numerous denominations themselves, often far short of accepting literal Biblical truth? Believers find their own way, and so it is with scientists who follow conventional belief systems.

However, one potential danger of teaching science in faith schools may be a relic of Darwin's contemporaries (and of course Darwin himself initially aimed for a church career), namely the well-intentioned attempt to imbibe the discipline with a moral structure. Yet as our current level of knowledge clearly shows, bearing in mind everything from natural selection to asteroid impact, we cannot ally ethical principles to scientific methods or knowledge. Scientific theories can be used for good or evil, but it is about as tenable to link science to ethics or moral development as it is to blame a cat for torturing its prey. Of course children require moral guidance, but it must be nurtured via other routes. Einstein wrote in 1930 of a sense of cosmic religious feeling which has no need for the conventional anthropomorphic deity but to my mind seems more akin to Buddhism. As such he believed that a key role of science (along with art) is to awaken and preserve this numinous-like feeling. I for one consider this is as far as science can go along the road to spirituality, but equally agree with Huxley's term agnosticism: to go beyond this in either direction with our current, obviously primitive state of understanding, is sheer arrogance. If we wish to inculcate an open mind in our children, we must first guarantee such a thought system in ourselves. All else is indoctrination, be it religious or secular.

One of the ironies of faith schools in a nation where two thirds of secondary school children do not see themselves as religious practitioners, is that they are generally considered to supply a high standard of education and as such are usually oversubscribed. But all in all, there is little evidence to support this notion, since any oversubscribed institution is presumably able to choose a higher calibre of student whilst claiming to the contrary. Current estimates suggest 15% of British children attend faith schools, with a higher proportion in some regions (such as over 20% of London's secondary school places) but as low as 5% in more rural areas. Clearly, parents who want a good education for their children are not being put off by the worry of potential indoctrination. As has become obvious over the past few years, there are large increases in attendance at school-affiliated churches just prior to the application period: a substantial number of parents are obviously faking faith in return for what they deem to be a superior education.

For the moment it seems science education in Britain has little to worry about from the fundamentalists, at least compared to the divisiveness and homophobia that the National Secular Society deem the most prominent results of increasing faith-based education. We must be careful to ensure that as taxpayers we do not end up funding creationist institutions, but we can do little to prevent private schools following this approach. On a positive note, the closest faith school to me has a higher level of science attainment than its non-religious rivals. I admit that I attended an Anglican school for three years and appear to have emerged with as plural a stance as could be wished for. Indeed, I look back fondly on the days of dangerous chemistry experiments before health and safety-guaranteed virtual demonstrations began to supplant this fun aspect of school science: if you haven't used a burning peanut to blow the lid off a cocoa tin, you haven't lived!

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