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?

Technorati Tags: dinosaurs, jurassic, palaeontology

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!

Technorati Tags: creationism, einstein, darwin, dawkins

How green is my alley? Reduce, reuse & recycle

British artist Richard Hamilton's 1957 definition of pop art included the terms 'transient', 'expendable', 'mass-produced', and 'Big Business'. We've come a long way since similar contemporary cultural attitudes led to throwaway clothing and disposable furniture, but there's still plenty that needs to be done before we achieve anything approaching sustainable development. The recent news articles showing that like the Pacific, the North Atlantic Ocean has its own enormous patch of floating plastic waste, clearly define a multinational problem: but what can the average Briton do to help the environment?

The three green 'R's of reduce, reuse and recycle involve a lot of statistics published by a variety of concerns, ranging from manufacturers to environmental groups. Going with the old saying that there are lies, damn lies and you-know-what, how can the public find a way through the minefield? As an example, estimates for the UK's annual waste total vary from 100 million to 400 million tonnes - although even the lower figure is more than enough! In recent years there have been several scandals involving potentially dangerous waste collected by local councils for recycling, only to be sent to developing countries where it is picked over by scavengers. Clearly, in some cases, out of sight is also out of mind.

Perhaps this shouldn't be too surprising considering how quickly we've had to adopt ecologically-motivated measures, but another concern is the enormous regional variation in recycling collection, waste processing and recovery. Lack of processing plants and a deficiency of recycling knowledge within councils supply yet another example of the postcode lottery. In response to this some local communities are taking matters into their own hands, such as the Somerset village of Chew Magna, where the inhabitants are attempting to gain zero waste status.

In addition to the lack of processing facilities another issue is sorting, although the use of high-tech approaches such as x-ray fluorescence and infra-red spectroscopy may increase efficiency, especially of plastics where recycling can create enormous savings in everything from oil to water. It isn't just the percentage that is recycled that counts, but how effective the processing and recovery methods are and whether as a nation we can reduce the amount of waste in the first place. Britain is an intensely consumerist nation and as if we need further proof, our household waste continues to grow by about 3% each year.

One of the most astonishing statistics (you see, they keep on cropping up), is the estimated 17.5 billion plastic bags given away in British shops every year. This amounts to over 130,000 tonnes of plastic, very few of which are composed of biodegradable material. An example of how quickly habits could change is shown by Ireland's introduction of a tax on plastic bags in 2002, which lead to an almost immediate reduction of over 90%. What's the difference to the UK? As far as I can tell, it boils down to the simple fact that unlike in Ireland, we have companies who make plastic bags: far be it from the Government to inhibit sales within our increasingly pitiful manufacturing base.

Despite the popularity of city allotments we are so divorced from food sources as to blindly follow use-by dates without actually checking the food itself. Recent evidence, including personal experiments by yours truly, show that in many cases the dates are wildly pessimistic (fingers crossed, I haven't been poisoned yet.) Again the figures vary widely, but estimates for food wastage in Britain range from 2.5 million to 8 million tonnes per year, which even for the lower figure equates to 18 million tonnes of carbon dioxide. Food safety scares have a lot to answer for, but surely effective food science education of adults as well as children is the obvious solution? After all, it would save us at least £10 billion per year on our shopping bills.

Of course it isn't just the consumer who is at fault: British industry must bear much of the blame. Every year we each spend up to one-sixth of our food budget on packaging, much of which uses standard sizes to cut manufacturing costs at the expense of material wastage. We could do worse than look at South Korea, where over the past decade legislation has reduced both the size and materials that can be used for packaging processed foods.

Another issue is planned obsolescence. Both the Trading Standards Institute and the Office of Fair Trading investigate consumer claims of items ceasing to work shortly after the initial warranty expires, but there are plenty of less obvious instances of products deliberately built to limits short of their potential working life, such as printer cartridges and rechargeable batteries. More insidious still is the use of advertising and clever marketing, combined with long-term release cycles, to promote a more rapid replacement of items than is really necessary. This 'obsolescence of desirability' is particularly obvious with mobile phones, which rapidly outstripped manufacturer's sales estimates in the early 1990s and are now updated on the basis of a fashionable new function or user interface rather than improvements to their core purpose. There can be no better illustration of the needlessly short life span of electronic goods than the seven metre tall WEEE Man sculpture at the Eden Project in Cornwall, which is composed of the consumer goods the average British citizen gets through in a lifetime - including no less than 35 mobile phones!

One irony is that the rapid development of storage formats over the past few decades has created a cycle of obsolescence from floppy disks to laser discs at a time we most need to counter expendability. Perhaps the current generation of 'virtual' devices such as Ipods and Ipads will help offset this, as long as their material and energy costs don't outweigh the savings in paper and packaging.

We cannot be in any doubt that things are changing for the better, but the big question is whether it is fast enough. The world's third largest retailer, Tesco, plans to be carbon neutral…in about forty years time. Many office buildings are already zero carbon and the Government plans for all new homes to be built to this standard from 2016. Meanwhile the Welsh firm Affresol has developed TPR, a wholly-recyclable substance stronger than concrete yet made mostly of waste and intended to provide load-bearing walls for buildings; fingers crossed for their pilot project!

Obviously just cutting back on domestic waste and power consumption will not do as much as reducing fossil fuel usage, but every little bit helps. A final shocking statistic: every Christmas this nation uses 8,000 tonnes of wrapping paper. Do we really need that amount? And as for carbon-trading - that's a whole other issue...

Are we alone? Wow, Little Green Men and the SETI faithful

According to the film version of Arthur C. Clarke's novel 2010: Odyssey Two, we now live in 'The Year We Make Contact'. Therefore it seems apt to take a quick look at the history of SETI, the Search for Extra-Terrestrial Intelligence, just in case fact should follow fiction. The recently-discovered antics of the Australian octopi that use coconut shells as mobile homes prove that it isn't just the music-loving, film-making and now liquid-quantifying chimpanzees who erode the boundaries between Homo sapiens and other animals. The Gallup mark mirror test has shown that apes, elephants, dolphins and even some birds have a degree of self-awareness exceeding that of human babies less than several months old. When combined with research into animal tool use and the archaeological evidence for rituals conducted by our extinct Neanderthal cousins, our species' mental abilities appear less and less distinctive. So if there are varying degrees of self-aware animals down here, what are the chances of intelligent life "up there"?

New analysis of the Murchison meteorite fragments which landed in Australia in 1969 has found 14,000 carbon-based compounds, including dozens of amino acids different from those known on Earth. If anything, this evidence is more intriguing than the now infamous Martian meteorite ALH 84001 which has so far failed to provide conclusive evidence of fossilised alien nanobacteria. But the idea of life being able to survive outside our comfortable biosphere has gained credence over the past few decades with the discovery of extremophiles, including the diverse organisms that live around submarine volcanic vents and the microbes that can survive gamma radiation several thousand times the dosage lethal to humans.

Whilst there has been a growth of interest in exobiology since the NASA experiments on Mars in the mid-1970s via the two Viking landers, a good deal of today's research investigates the notion of intelligent life elsewhere, largely via radio astronomy. Notable organisations include the Planetary Society, co-founded by the late Carl Sagan, and the Seti Institute, co-founded by Jill Tarter, the real-life model for Sagan's fictional Contact protagonist Eleanor Arroway. Yet despite the lack of positive data after half a century's effort, both the pro and con lobbies maintain passionate support for their ideas. One of the best-known SETI pioneers is American astronomer and astrophysicist Frank Drake, whose eponymous equation has been argued by both sides despite being deemed by some, including author Michael Crichton, as scientifically worthless. This stems from the fact that most of the values in the Drake equation, aiming to establish the potential number of civilisations in the galaxy capable of interstellar communication, are as unknown as when first written in 1960. Over the decades many researchers have had a go at 'filling in the blanks' and achieved results ranging from one (us) to over a million. Clearly, it is not an equation that can be resolved utilising our current knowledge of astrophysics, biology and almost everything in between.

As might be expected the UK's involvement in SETI has been somewhat minimal, although the 76-metre diameter Lovell Radio Telescope at Jodrell Bank has been used intermittently in this context since the late 1990s. Last month even saw the Royal Society host a SETI conference that included such astronomical luminaries as Martin Rees, Jocelyn Bell Burnell and Frank Drake. Unfortunately the traditional British no-nonsense approach lost Jodrell Bank in particular (and the country in general) its chance for pioneering SETI research when Bernard Lovell, in a decision he apparently later regretted, turned down a request to use the very same, then-named Mark 1, radio telescope in 1959.

Although over four hundred planets have been discovered (mostly indirectly) around other stars, none are obviously in the 'Goldilocks zone' where it is believed conditions are suitable for life. Having said that, the recent discoveries of water, mostly as ice, on the Moon, Mars, and two or three other satellites, are obviously positive signs. Then again, there is an enormous difference between those who support the notion of alien microbial life as opposed to intelligent organisms able to transmit signals between solar systems. As early as 1950 physicist Enrico Fermi developed his famous paradox which states that if there are any alien societies capable of interstellar travel, or just communications technology comparable to ours, then we should have found evidence by now. Despite several false alerts such as Jocelyn Bell Burnell's 1967 discovery of pulsars (which she initially labelled as LGM or 'Little Green Men') and the never-repeated 'Wow!' signal detected at Ohio State University in 1977, there has been no unequivocal evidence from the electromagnetic spectrum. In addition, and despite the plethora of orbiting telescopes from Hubble to WISE, there is no evidence for astro-engineering artefacts such as Dyson spheres that a more advanced civilisation might be able to construct.

One international project that has shown the immense level of international grass roots support for the hypothesis is SETI@home, which over the past decade has utilised five million home computers to process radio telescope signal data. Even though such current projects do not involve public money or remove time from research with seemingly more potential of success, there is still plenty of vociferous opposition, even from the scientific community. Arguments range from the practical, such as if we are already moving to fibre optics and digital signals perhaps radio broadcasts are too rare to be detected (some groups have now started laser-based research), to intense speculation on alien motives, which is clearly more in the realm of psychology than science. One of more interesting of the latter is the idea of deliberately non-communicative aliens: since like everyone else SETI researchers have the hard-wired human instinct for exploration, how can we have knowledge of an extraterrestrial psyche until we achieve contact? We surmise at our peril!

Of course another problem facing SETI is the manner in which it has been linked to the lunatic fringe. The unfortunate interest shown in the hypothesis by everyone from New Age mystics to conspiracy theorists taints the idea as verging on pseudoscience, regardless of how scientific the investigations themselves have been. In 1993 NASA's main SETI programme, at one point renamed the High Resolution Microwave Survey in an effort to remove the 'giggle factor', was cancelled after less than one year's operation. But then is it that surprising that US Government support has frequently been withdrawn, leaving only privately funded SETI projects as per today? High-profile supporters including Steven Spielberg and Microsoft co-founder Paul Allen may have boosted its status, but is SETI strictly scientific despite its methods and technology? After all, we could listen for thousands of years without receiving evidence, but as the old adage goes, absence of evidence is not necessarily evidence of absence.

Certainly the zeal with which Carl Sagan, probably the best known SETI advocate from the 1970s to 1990s, approached the enterprise had an almost religious air to it. His novel Contact develops this aspect by making the heroine rely solely on faith rather than physical evidence of her meeting with an extra-terrestrial. It could be argued that by presenting the alien in the guise of the protagonist's father, Sagan replaced conventional religiosity with a paternal God-like being with astounding powers. As Arthur C. Clarke's Third Law states (and as the Aztecs and many others found to their cost): 'Any sufficiently advanced technology is indistinguishable from magic'.

One of Sagan's early claims from the era of Vietnam and Watergate was that receipt of a signal would not only show the possibility of surviving technological adolescence but might also provide information to help us do the same. Since scientific thought is entrenched in the historical and cultural biases of the scientists involved, not to mention the increasing use of models and metaphors at the cutting edge, how easy would it be to understand even scientific concepts from a culture probably millennia more advanced than our own? Even if we could decipher alien scientific data, the next obvious problem is might we inadvertently destroy ourselves via some form of industrial accident, or developments in the $1.2 trillion per annum arms race, brought about by precipitant use of advanced technology? This displays another danger of SETI research: the wide-ranging but pointless speculation in lieu of hard evidence. Until we receive a message, all such conjecture is only of use to acknowledge our own hopes and fears. Even the mildly optimistic notion of extra-terrestrial contact bringing wonder or enchantment to humanity could be countered by slow translation progress in this era of the 140-character Tweet. When the news reports over the ALH 84001 meteorite were at their height in the mid-1990s, I remember work colleague telling me she was heartily sick of hearing about it. Clearly one person's mysterium fascinans (as Stephen Jay Gould might have phrased it), is another's mind-numbing tedium!

How long we will keep listening for is also open to question. If after a few more decades of concerted effort we have still not found definitive evidence, one possibly positive outcome might be the increased promotion of eco-awareness via the obvious rarity of own biologically-active planet. But current estimates suggest we have so far undertaken only about one hundred-trillionth of the radio coverage deemed necessary for a thorough search. It will be at least decades before we can afford to build even robot craft capable of travelling interstellar distances in reasonable spans of time, so until then we have little choice but to rely on our various types of receiver. So why bother at all? For the comparatively small sums involved, there's not much else that could provide such an astonishing potential return. As for the pessimists out there, I can offer nothing better than Monty Python's Eric Idle: "And pray that there's intelligent life somewhere out in space / 'Cause there's bugger all down here on Earth!"

Technorati Tags: seti, sagan

Palaeontological pastimes: fossicking for all the family

What do the Isle of Wight, the Dorset coast and a park in south-east London have in common? Answer: they are all popular stomping grounds for amateur fossil hunters, adults and children alike. Discovering fossils in Britain has a long pedigree, as shown by the antiquity of common names for popular species such as the Jurassic oyster Gryphaea: the Devil's toenail. Equally telling are the museum specimens of ammonites with snake heads carved on them, which were sold over the centuries as 'petrified serpents'. Whilst carving heads doesn't exactly do much for fossils in scientific sense, it is at least an improvement on the Chinese folk tradition of grinding up 'dragon bones' to make medicines!

Fossicking as a popular activity has grown enormously over the past few decades, both in the UK and elsewhere. During the first half of the nineteenth century talented British amateurs such as Mary Anning and Gideon Mantell pioneered techniques to respectively excavate and examine Mesozoic fossils, but since then the field appears to have almost wholly dominated by professionals. So why is it that over the past few decades fossil hunting has become a widespread activity for both children and their parents?

It's probably best to start with two books concerning those ubiquitous prehistoric beasts, the dinosaurs. Until the 1980s most books portrayed them as lumbering, frequently swamp-dwelling animals: slow, simple-minded, and boringly monochrome. Then in 1986 American palaeontologist Robert Bakker wrote The Dinosaur Heresies: New Theories Unlocking the Mystery of the Dinosaurs and Their Extinction, which promoted a more active, bird-like metabolism. Bakker's research (in many aspects now considered more mainstream than heretical) had the good fortune to be published at the same time that research into the 65 million year old iridium layer was gaining attention. In 1990, Michael Crichton's novel Jurassic Park became a bestseller shortly before the publication of a flurry of articles and papers discussing the Chicxulub crater in Mexico. For a while this enormous impact crater was combined with the worldwide iridium layer to offer a definitive solution to the dinosaurs' demise via asteroid impact, although the hypothesis has becoming increasingly untenable since. In the meantime, Steven Spielberg's 1993 film adaptation of Crichton's book became the highest-grossing film in history, confirming that dinosaurs were back in the public imagination on an unprecedented scale.

The continual development of computer-generated graphics has since led to numerous dramas and documentaries featuring these and other extinct ecosystems, often courtesy of the Discovery Channel and the BBC. Museums have also got in on the act, with dynamic, frequently animatronics exhibits ranging from the three-quarter sized Tyrannosaurus Rex at the Natural History Museum in London to the tiny hatchling at Oxford's equivalent. There have also been some international theatrical exhibitions featuring full-size reconstructions, including the £10 million Walking with Dinosaurs show at the O2 and Wembley Arena, as well as the new temporary exhibition at Parklife Oxford Street in London. Dinomania and then some!

Although these commercial enterprises have only been made feasible by the advances in animatronics and computer graphic technology, they appear closely tied to the flood of new finds and resulting theories. Many specialists now speak of a golden age of dinosaur discovery, supported by the recognition of a new species every few months and computers used to rapidly produce life-like reconstructions. The number of exciting finds, especially from China, supports the idea of a dinosaur renaissance, although hasty speculation on the dino-bandwagon often seems to drown out sober fact. One recent key discovery is the feathers and protofeathers found on various species: current research of their microscopic melanosomes has led to a claim of multi-coloured, possibly striped dinosaurs; a far cry from the bland grey and brown illustrations I remember from the 1970s. With embryo-containing eggs and nests also being found around the world, many aspects of dinosauria are becoming as well known as species alive today. Perhaps it is the increasing familiarity of some of these animals (as in their resemblance to giant proto-birds) which helps generate a feedback loop between scientific exploration and media exposition. The day of the dull dinosaur is over.

As for the British Isles, the popularity of dinosaurs has been used to generate enormous interest in amateur fossil hunting, with the Isle of Wight, home to the earliest ancestor of T-Rex, often considered the best location in Europe for finding dinosaurs. The island contains the Dinosaur Isle and the Dinosaur Farm Museum attractions, which combined with Norfolk's Dinosaur Adventure Park show there's no shortage of family-oriented 'edutainment'.

Of course there are many other genera to be found in the UK: the three-volume set of British fossils published by the Natural History Museum runs to over 500 pages. The main groups I have found whilst fossicking around the country are echoed by the limited choice of native specimens available in fossil shops, namely belemnites, ammonites, shark's teeth, and to a lesser extent, trilobites. Whilst these are mostly small specimens (anything large tends to be discovered by commercial operators after winter storms), there are still occasional finds showing the potential for amateurs. These include the 600,000 year old elephant found at West Runton beach in Norfolk; and Baryonyx, a 9.5 metre long fish-eating dinosaur that was discovered in a Surrey clay pit.

Many locations offered organised walks, including some just for one family at a time. Herein lies another reason for the popularity: many fossil-bearing strata are found in extremely accessible locations such as the coastline of popular holiday resorts, so it's far easier to combine a beach holiday with a fossil hunt than at equivalent, frequently remote sites in Australia or the USA. There is even a Family Fossil Hunt course on the Pembrokeshire Coast in Wales, aimed at introducing families to the joys of fossicking. For those who come away empty-handed (often the adults, since children usually have better eyesight and are closer to the ground), numerous gem shops and websites sell fossils in addition to paraphernalia such as geology hammers, goggles, and magnifiers. Again, many items are clearly aimed at children, including party bags (some with chocolate ammonites) and starter sets containing items such as dinosaur coprolites (fossilised dung).

By and large, fossil hunting is a fairly harmless activity. As long as you keep an eye on the tide and don't dig into cliff faces, there's not much that can go wrong with a leisure pursuit that can cost nothing more than some ziplock bags to contain your finds. If fossils are not extracted when exposed, the weather or wave action will soon erode or fragment them. As long as any unusual specimens are reported it's doubtful scientific information is being lost (unlike with metal detectorists, where archaeological context is everything). Without sounding too much like a public information film from the 1950s, fossicking is a healthy pursuit for all the family that can help promote interest in biodiversity and evolution (although if it is anything like what can be overheard at the Natural History Museum, the pre-teens often know more about it - Greco-Latin species names included - than their parents). And after all, in many locations as soon as you get bored you can always go back to building sandcastles!

Technorati Tags: dinosaur, fossil, palaeontology