Thursday, 25 February 2010

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!"

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Monday, 15 February 2010

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!

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Thursday, 4 February 2010

Don't Catch the Cod: the ebb and flow of marine biology in the UK

About quarter of a century ago I was walking along the north Welsh coast when I came across an extraordinary sight: dozens of large, pink jellyfish, some a metre across, were lying stranded on the beach. I later discovered that these were Rhizostoma octopus - jellyfish despite the name and so-called because of their eight tentacles - marooned during a gathering to breed. In a country not known for unusual fauna, events like this give food for thought about the unknown creatures living just off our shores. Since fifty to eighty percent of all life resides in the sea, there's obviously a lot more out there besides cod, haddock and plaice. Another exotic but almost unknown organism that inhabits British waters is Regalecus glesne, a species of oarfish that grows up to 11 metres long and is therefore probably the longest bony fish in existence today. With more than a passing resemblance to the classic sea serpent of yore this king of herrings has rarely been seen alive, with only around fifty known strandings over the past two and a half centuries. Incidentally, this category excludes the cartilaginous basking shark, at 20 tons the second largest fish in the world and commonly to be found around the British coastline. Lucky for us, it's a filter feeder!

For a nation where it is impossible to live much more than 100 km from the sea, we appear astoundingly ignorant of our marine neighbourhood. In an early example of what has now become a cliché, pioneer environmentalist Rachel Carson pointed out in The Sea Around Us (1951), that the oceans remain the last great frontier on Earth. We are only now realising just how little we know about the role marine organisms play in everything from climate stability to food chains. Speaking of marine cuisine, a thoughtful example of changing attitudes can be found in Arthur C. Clarke's 1957 novel The Deep Range, which concerns the herding of whales for food, at least until a Buddhist leader campaigns for the slaughter to stop. Interestingly, it was the recordings of humpback whale song in the 1960s that started the anti-whaling movement, gaining popularity through the 1970s (including a UK top-forty single Don't Kill the Whale in 1978), leading to an eventual, if not outright, ban in 1986. Not that, if given half a chance, several nations wouldn't like to see 'scientific whaling' increased to the level of commercial operations...

If whaling shows the traditional viewpoint of the oceans as a limitless larder, another popular notion but somewhat at odds is to treat the sea as an ever-obliging rubbish tip. Despite the likes of Jacques Cousteau starting campaigns as early as 1960 to halt the dumping of nuclear waste from ships, it is generally recognised that the Irish Sea is one of the most radioactive in the world thanks to land-based pipelines. The rest of our coastal waters aren't much better off, being subject to pollution from oil, bilge water, sewage and nitrogen fertiliser run-off, all of which do little for the health of marine organisms. As an extreme example, in 1988 half of Britain's seal colonies were lost due to immune deficiency linked to pollution, with smaller-scale outbreaks reoccurring since.

Going back to the perception of the sea as a food store par excellence, the E.U. announced last year that over 80% of fish stocks in the region were over-fished, the classic example of the fishfinger's friend, North Atlantic cod, having reduced by over 98% in three decades. Whilst many people may not worry whether their children eat pollock/pollack or coley instead, a rapid decline in a few species could have unforeseen consequences, as with the proliferation of a rapidly expanding Humboldt squid population which is currently supplanting the dwindling number of sharks as top predator off Mexico's west coast.

But at least as important as well-known species are the minute marine organisms that will continue to require a high level of research for decades to come. Microscopic phytoplankton are responsible for at least half of all photosynthetic activity, thereby regulating atmospheric oxygen content, in addition to being the base of many food chains. Evidence is even beginning to favour the CLAW hypothesis (the 'L' being co-author James Lovelock), in which one group of phytoplankton is viewed as an essential component of the cloud condensation cycle. So what happens 'down there' may have an enormous influence of what goes on over our heads. The Gaia hypothesis (in the strictest feedback loop sense) could be alive and well, after all...

Whilst we are currently lacking the kind of public fervour seen in the 1970s anti-whaling campaigns, marine biology in the UK appears to be flourishing. There are about sixty higher education courses to chose from with an apparently good success rate in obtaining relating jobs. The subject is often taught as one of several components, including conservation and oceanography; what interests me is this way it so readily interacts with other disciplines, ranging from chemistry to meteorology, and thereby uses a wide gamut of scientific tools, from observation satellites to remotely-operated vehicles or ROVs. On that basis alone it is currently one of the most exciting areas of science in Britain, as well as being increasingly relevant to our quality of life. One scheme involving British scientists in recent years was some of the earliest research into pouring iron sulphate powder into the oceans, in an effort to stimulate plankton production (and thereby other marine life), reduce carbon dioxide, and decrease atmospheric temperature. The recent licences issued for nine new offshore wind farms around the UK will presumably provide research for marine biologists too, as current studies indicate the short-term disruption is more than compensated for by the turbines doubling as artificial reefs.

An example outside the scope of the promising Marine and Coastal Access Act 2009 but now under active consultation, is the controversial campaign to turn the Chagos archipelago in the British Indian Ocean Territory into the world's largest marine reserve. Although protection status would obviously be a positive move, the primary downside would be the permanent dispossession of the local inhabitants: such is the complexity facing sustainable development projects. Closer to home, we can't all be involved in marine conservation, but it's very easy for anyone to help preserve biodiversity - simply find an alternative to cod to go with your chips!

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