Showing posts with label Jurassic World. Show all posts
Showing posts with label Jurassic World. Show all posts

Wednesday 13 June 2018

Debunking DNA: A new search for the Loch Ness monster

I was recently surprised to read that a New Zealand genomics scientist, Neil Gemmell of Otago University, is about to lead an international team in the search for the Loch Ness monster. Surely, I thought, that myth has long since been put to bed and is only something exploited for the purposes of tourism? I remember some years ago that a fleet of vessels using side-sweeping sonar had covered much of the loch without discovering anything conclusive. When combined with the fact that the most famous photograph is a known fake and the lack of evidence from the plethora of tourist cameras (never mind those of dedicated Nessie watchers) that have convened on the spot, the conclusion seems obvious.

I've put together a few points that don't bode well for the search, even assuming that Nessie is a 'living fossil' (à la coelacanth) rather than a supernatural creature; the usual explanation is a cold water-adapted descendant of a long-necked plesiosaur - last known to have lived in the Cretaceous Period:
  1. Loch Ness was formed by glacial action around 10,000 years ago, so where did Nessie come from? 
  2. Glacial action implies no underwater caves for hiding in
  3. How can a single creature maintain a long-term population (the earliest mentions date back thirteen hundred years)? 
  4. What does such a large creature eat without noticeably reducing the loch's fish population?
  5. Why have no remains ever been found, such as large bones, even on sonar?
All in all, I didn't think much of the expedition's chances and therefore I initially thought that the new research would be a distinct waste of money that could be much better used elsewhere in Scotland. After all, the Shetland seabird population is rapidly decreasing thanks to over-fishing, plastic pollution and loss of plankton due to increasing ocean temperatures. It would make more sense to protect the likes of puffins (who have suffered a 98% decline over the past 20 years), along with guillemots and kittiwakes amongst others.

However, I then read that separate from the headline-grabbing monster hunt, the expedition's underlying purpose concerns environmental DNA sampling, a type of test never before used at Loch Ness. Gemmell's team have proffered a range of scientifically valid reasons for their project:
  1. To survey the loch's ecosystem, from bacteria upwards 
  2. Demonstrate the scientific process to the public (presumably versus all the pseudoscientific nonsense surrounding cryptozoology)
  3. Test for trace DNA from potential but realistic causes of 'monster' sightings, such as large sturgeon or catfish 
  4. Understand local biodiversity with a view to conservation, especially as regards the effect caused by invasive species such as the Pacific pink salmon. 
Should the expedition find any trace of reptile DNA, this would of course prove the presence of something highly unusual in the loch. Gemmell has admitted he doubts they will find traces of any monster-sized creatures, plesiosaur or otherwise, noting that the largest unknown species likely to be found are bacteria. Doesn't it seem strange though that sometimes the best way to engage the public - and gain funding - for real science is to use what at best could be described as pseudoscience?

Imagine if NASA could only get funding for Earth observation missions by including the potential to prove whether our planet was flat or not? (Incidentally, you might think a flat Earth was just the territory of a few nutbars, but a poll conducted in February this year suggests that fully two percent of Americans are convinced the Earth is a disk, not spherical).

Back to reality. Despite the great work of scientists who write popular books and hold lectures on their area of expertise, it seems that the media - particularly Hollywood - are the primary source of science knowledge to the general public. Hollywood's version of de-extinction science, particularly for ancient species such as dinosaurs, seems to be far better known than the relatively unglamorous reality. Dr Beth Shapiro's book How to clone a mammoth for example is an excellent introduction to the subject, but would find it difficult to compete along side the adventures of the Jurassic World/Park films.

The problem is that many if not most people want to believe in a world that is more exciting than their daily routine would suggest, with cryptozoology offering itself as an alternative to hard science thanks to its vast library of sightings over the centuries. Of course it's easy to scoff: one million tourists visit Loch Ness each year but consistently fail to find anything; surely in this case absence of evidence is enough to prove evidence of absence?

The Loch Ness monster is of course merely the tip of the mythological creature iceberg. The Wikipedia entry on cryptids lists over 170 species - can they all be just as suspect? The deep ocean is the best bet today for large creatures new to science. In a 2010 post I mentioned that the still largely unexplored depths could possibly contain unknown megafauna, such as a larger version of the oarfish that could prove to be the fabled sea serpent.

I've long had a fascination with large creatures, both real (dinosaurs, of course) and imaginary. When I was eight years old David Attenborough made a television series called Fabulous Animals and I had the tie-in book. In a similar fashion to the new Loch Ness research project, Attenborough used the programmes to bring natural history and evolutionary biology to a pre-teen audience via the lure of cryptozoology. For example, he discussed komodo dragons and giant squid, comparing extant megafauna to extinct species such as woolly mammoth and to mythical beasts, including the Loch Ness Monster.

A few years later, another television series that I avidly watched covered some of the same ground, namely Arthur C. Clarke's Mysterious World. No less than four episodes covered submarine cryptozoology, including the giant squid, sea serpents and of course Nessie him (or her) self. Unfortunately the quality of such programmes has plummeted since, although as the popularity of the (frankly ridiculous) seven-year running series Finding Bigfoot shows, the public have an inexhaustible appetite for this sort of stuff.

I've read that it is estimated only about ten percent of extinct species have been discovered in the fossil record, so there are no doubt some potential surprises out there (Home floresiensis, anyone?) However, the evidence - or lack thereof - seems firmly stacked against the Loch Ness monster. What is unlikely though is that the latest expedition will dampen the spirits of the cryptid believers. A recent wolf-like corpse found in Montana, USA, may turn out to be coyote-wolf hybrid, but this hasn't stopped the Bigfoot and werewolf fans from spreading X-Files style theories across the internet. I suppose it’s mostly harmless fun, and if Professor Gemmell’s team can spread some real science along the way, who am I to argue with that? Long live Nessie!

Monday 28 September 2015

Resurrecting megafauna: the various problems of de-extinction


The record-breaking success of Jurassic World proves that if there's anything a lot of people want to see in the animal kingdom it is species that are both large and fierce. Unfortunately, in these post-glacial times that type of fauna has been much reduced and will no doubt wane even further - not that I particularly wish to encounter an apex predator at close quarters, you understand.

Hollywood, of course, has much to answer for. There was plenty of poor science in the original Jurassic Park movie - the use of gap-filling frog DNA being a far worse crime in my book than the over-sized velociraptors (think Achillobator and similar species) but the most recent film in the franchise has pointedly ignored the advances in dinosaur knowledge made in the intervening period. Perhaps a CGI test of a feathered T-Rex looked just to comical?

In contrast, the amount of publically-available material discussing de-extinction has increased exponentially in the two decades since Jurassic Park was released, with the line between fact and fiction well and truly blurred. That's not to say that an enormous amount hasn't been learned about the DNA of extinct species during this period. I recently watched a rather good documentary on the National Geographic channel (yes, it does occasionally happen) about the one-month old baby mammoth Lyuba, recovered in Siberia almost forty-two thousand years after she died. The amount of genetic information that has been recovered from mammoths is now extremely comprehensive, but then they were alive until almost yesterday at geological timescales. Needless to say the further back in time a creature existed, the more problematic it is to retrieve any genetic material.

A lot has been written about the methods that have been, or could in the near future, be used to resurrect ancient animals. Some procedures involve the use of contemporary species as surrogate parents, such as elephants standing in for mother mammoths. But it seems fair to say that all such projects are finding difficulties rather greater than originally planned. One common misconception is that any resurrected animal would be a pure example of its kind. Even the numerous frozen mammoth carcasses have failed to supply anywhere near a complete genome and of course it isn't just a case of filling in gaps as per a jigsaw puzzle: one primary issue is how to know where each fragment fits into the whole. Our knowledge of genetics may have advanced enormously since Watson and Crick's landmark 1953 paper, but genetic engineering is still incredibly difficult even with species that are alive today. After all, Dolly the sheep wasn't a pure clone, but had nuclear DNA from one donor and mitochondrial DNA from another.

Therefore instead of resurrecting extinct species we would be engineering hybrid genomes. Jurassic World took this process to the extreme with Indominus rex, a giant hybrid of many species including cuttlefish! Some research suggests that the most of the original genes of any species over a million years old – and therefore including all dinosaurs – might never be recovered. Something  terrible lizard-ish may be built one day, but it would be closer to say, a chicken, with added teeth, a long bony tail and a serious attitude problem. In fact, George Lucas has been a key funder of the chickenosaurus project with aims along these lines. Let's hope he doesn't start building an army of them, totally obedient clones, ready for world domination…oh no, that was fiction, wasn't it?

But if – or more likely, when – creating variants of extinct species becomes possible, should we even attempt it? Apart from the formidable technical challenges, a lot of the drive behind it seems to be for populating glorified wildlife parks, or even worse, game reserves. The mock TV documentary series Prehistoric Park for example only contained large animals from various periods, frequently fierce carnivores, with no attention given to less conspicuous creatures or indeed flora. This gee-whiz mentality seems to follow a lot of the material written about de-extinction, masking some very serious long-term issues in favour of something akin to old-style menageries. Jurassic Park, in fact.

A big question that would be near impossible to answer in advance is whether such a species would be able to thrive or even survive in a climate far removed from the original, unless there was major genetic engineering just for such adaptive purposes. Again, the further back the animal lived, the less likely it is that there is a contemporary habitat close to the original. It may be possible to recreate glacial steppes suitable for some mammoth species, but what about the Earth of ten million or one hundred million years ago? Prehistoric Park got around the issue for its Carboniferous megafauna by housing them in a high oxygen enclosure, which is certainly a solution, if something of a fire hazard!

Any newly-created animal will lack the symbiotic microbial fauna and flora of the original era, but I've not seen much that tackles this issue. I suppose there could be a multi-stage process, starting with deliberate injections of material in vitro (or via the host /mother). But once the animal is born it will have to exist with whatever the local environment/habitat has to offer. The chimerical nature of the organism may help provide a solution, but again this takes the creature even further from the original.

Then there is the rather important issue of food. To his credit, Michael Crichton suggested in Jurassic Park that herbivorous dinosaurs swallowing gizzard stones might accidentally eat berries that their metabolism couldn't handle. It would be extremely expensive to maintain compounds large enough for megafauna that are constantly kept free of wind-blown, bird-dropped and otherwise invasive material dangerous to the animals.

If the hybrids were allowed free reign, what if they escaped or were able to breed naturally? Given a breeding population (as opposed to say, sterilised clones) evolution via natural selection may lead them in a new direction. It would be wise to consider them as an integral part of the ecosystem into which they are placed, remembering Darwin's metaphor of ten thousand sharp wedges. Is there a possibility that they could out-compete modern species or in some other way exacerbate the contemporary high rate of extinction?

I've previously discussed the dangers of deliberate introduction of foreign species for biological control purposes: surely introducing engineered hybrids of extinct species is the ultimate example of this process? Or would there be a complete ban on natural reproduction for resurrected species, with each generation hand-reared from a bank of genetic material? At this point it should be clear that it isn't just the nomenclature that is confusing.

Some research has been undertaken to investigate the de-extinction of species whose demise during the past few centuries can clearly be blamed on humans, obvious examples being the Tasmanian tiger and the nine species of New Zealand moa. It could be claimed that this has more to do with alleviating guilt than serving a useful purpose (assuaging crimes against the ecosystem, as it were) but even in these cases the funds might be better turned towards more pressing issues. After all, two-thirds of amphibian species are currently endangered, largely due to direct human action. That's not to say that such money would then be available, since for example, a wealthy business tycoon who wants to sponsor mammoth resurrection - and they do exist - wouldn't necessarily transfer their funding to engineering hardier crops or revitalising declining pollinating insect species such as bees.

As it happens, even species that existed until a few hundred years ago have left little useable fragments of DNA, the dodo being a prime example. That's not to say that it won't one day be retrievable, as shown by the quagga, which was the first extinct species to have its DNA recovered, via a Nineteenth Century pelt.

As Jeff Goldman's chaos mathematician says in Jurassic Park, "scientists were so preoccupied with whether or not they could that they didn't stop to think if they should". Isn't that a useful consideration for any endeavour into the unknown? If there's one thing that biological control has shown, it is to expect the unexpected. The Romans may have enjoyed animal circuses, but we need to think carefully before we create a high-tech living spectacle without rather more consideration to the wider picture than appears to currently be the case.