Science, God, and the ultimate evolutionary question

Until science proves the origin of the very first cells, many will wheel out God as the default expl

Until science proves the origin of the very first cells, many will wheel out God as the default explanation.

No-one who has visited Richard Dawkins' website recently would have failed to notice the prominence given to an award being offered of up to 2 million dollars. Unfortunately for most of us, nobody will be granted the funding unless they put together a proposal for scientific research into the origin of life on our planet.

It's hardly a surprise that the site should draw attention to the award. After all, however much we think that we know about evolution, science is far from providing a confident explanation of the origin of the very first cells from which all life evolved. Until this gap in scientific knowledge is filled, many believers will continue to resort to God as the default explanation. For some, it must have been God who planted the first living cells on the planet, before leaving the stage and letting evolution take over. For others, the fact that no-one can prove how life originated sounds the death knell for evolution itself but is music to the ears of those who believe in Adam and Eve.

But are they right? Is science incapable of explaining the emergence of the first cells from which all life originated without the need for God?

In 1953 biologist Stanley Miller set up an experiment in the lab, intended to recreate what scientists call the earth's "primordial soup" when life first appeared 3.5 billion years ago. He created a sealed environment comprising boiling water and electric probes to simulate the effect of lightening on some of the young planet's hot waters. Thrown into the mix were methane, ammonia and hydrogen, the gases believed to be present on the early earth. The aim was to see whether anything related to life would form. Within a week, five amino acids had appeared in the water. This was a stunning result. After all, amino acids are the molecules which join up to form proteins inside living cells.

But to create proteins - and therefore life - amino acids must be strung together in a very specific order. And cells require DNA to do this. But how could something as complex as DNA have come into existence? Miller's experiment didn't answer that.

A possible explanation was found after a meteorite, slightly older than earth, crashed down in Australia in 1969. Amazingly one of the DNA bases was found inside the rock. Since the early earth was bombarded by meteorites for millions of years, this raises the tantalising possibility that DNA and RNA could have arrived here on meteorites around the time that life first appeared on the planet. This provides a partial explanation of how the amino acids could have developed into life.

But there are problems with the idea that life began in a Miller-like primordial soup. Analysis of ancient rocks has made it plain that at the time that life appeared, the earth was no longer rich in methane, ammonia and hydrogen. Besides, any soup would have been thermodynamically flat. This means that there was probably nothing to force the various molecules to react with each other, whether or not extraterrestrial DNA and RNA molecules were also present. And so far, scientists haven't been able to explain how the necessary molecules would have come together without a cell membrane.

But there is a different theory which addresses all these concerns.

It is well-known that the continents have been drifting apart throughout the lifetime of the planet. This is due to the movement of tectonic plates below the oceans. As these plates strike each other, new rocks are exposed to the sea water. This creates alkaline hydrothermal vents. The water physically reacts with the rocks and this releases heat along with gases reminiscent of Miller's experiments. As a result, warm alkaline hydrothermal fluids percolate into the cold oceans and, near the vents, structures are created which look rather like stalagmites and which are riddled with tiny compartments. These compartments could have been ideal places for chemical compounds from the gases to concentrate and combine to form early life in a fairly enclosed environment.

Although the existence of these vents had been predicted decades ago, it wasn't until 2000 that one was discovered in a part of the Atlantic Ocean which has been named Lost City. Scientists have analysed the cell-sized pores in the structures which were found there and concluded that they were almost ideal reaction vessels for producing the first life. What's more, the chemical imbalance between the sea water and the gases could have created an electrical charge which in turn possibly caused the chemical reactions needed to kick-start the creation of life.

But as I mentioned earlier, it's not sufficient to work out how the first amino acids may have appeared. It's also necessary to explain how DNA could have come onto the scene. Unfortunately DNA can't evolve without proteins. And proteins can't evolve without DNA.

Many scientists believe that the answer lies in the RNA World Theory. In 2007 it was discovered that nucleotides (and so RNA) could grow in simulated vents. At around the same time a scientific paper was published which concluded that RNA may have developed by living inside mineral cells in the vents. Biochemist Nick Lane believes once that had happened, RNA may have changed to DNA virtually spontaneously.

And so the hydrothermal vents theory provides a plausible account of how the first life could have formed on earth along with the DNA which was necessary to replicate it. But the theory certainly has difficulties. In fact, a similar theory based on a different type of vents, black smokers, is now generally given short shrift by the scientific community. Perhaps the hydrothermal vents theory will likewise come unstuck.

This is a difficult area of science. No doubt whoever receives that award, will have to work hard to earn every cent.

Andrew Zak Williams has written for the Independent and the Humanist and is a contributor to Skeptic Magazine. His email address is: andrewbelief@gmail.com

Photo: Getty
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A Fox among the chickens: why chlorinated poultry is about more than what's on your plate

The trade minister thinks we're obsessed with chicken, but it's emblematic of bigger Brexit challenges.

What do EU nationals and chlorinated chickens have in common? Both have involuntarily been co-opted as bargaining chips in Britain’s exit from the European Union. And while their chances of being welcomed across our borders rely on vastly different factors, both are currently being dangled over the heads of those charged with negotiating a Brexit deal.

So how is it that hundreds of thousands of pimpled, plucked carcasses are the more attractive option? More so than a Polish national looking to work hard, pay their taxes and enjoy a life in Britain while contributing to the domestic economy?

Put simply, let the chickens cross the Atlantic, and get a better trade deal with the US – a country currently "led" by a protectionist president who has pledged huge tariffs on numerous imports including steel and cars, both of which are key exports from Britain to the States. However, alongside chickens the US could include the tempting carrot of passporting rights, so at least bankers will be safe. Thank. Goodness. 

British farmers won’t be, however, and that is one of the greatest risks from a flood of "Frankenfoods" washing across the Atlantic. 

For many individuals, the idea of chlorinated chicken is hard to stomach. Why is it done? To help prevent the spread of bacteria such as salmonella and campylobacter. Does it work? From 2006-2013 the Centers for Disease Control and Prevention reported an average of 15.2 cases of salmonella per 100,000 people in the US (0.015 per cent) – earlier figures showed 0.006 per cent of cases resulted in hospitalisation. In 2013, the EU reported the level at 20.4 cases per 100,000, but figures from the Food Standards Agency showed only 0.003 per cent of UK cases resulted in hospitalisation, half of the US proportion.

Opponents of the practice also argue that washing chickens in chlorine is a safety net for lower hygiene standards and poorer animal welfare earlier along the line, a catch-all cover-up to ensure cheaper production costs. This is strongly denied by governing bodies and farmers alike (and International Trade Secretary Liam Fox, who reignited the debate) but all in all, it paints an unpalatable picture for those unaccustomed to America’s "big ag" ways.

But for the British farmer, imports of chicken roughly one fifth cheaper than domestic products (coupled with potential tariffs on exports to the EU) will put further pressure on an industry already working to tight margins, in which many participants make more money from soon-to-be-extinct EU subsidies than from agricultural income.

So how can British farmers compete? While technically soon free of EU "red tape" when it comes to welfare, environmental and hygiene regulations, if British farmers want to continue exporting to the EU, they will likely have to continue to comply with its stringent codes of practice. Up to 90 per cent of British beef and lamb exports reportedly go to the EU, while the figure is 70 per cent for pork. 

British Poultry Council chief executive Richard Griffiths says that the UK poultry meat industry "stands committed to feeding the nation with nutritious food and any compromise on standards will not be tolerated", adding that it is a "matter of our reputation on the global stage.”

Brexiteer and former environment minister Andrea Leadsom has previously promised she would not lower animal welfare standards to secure new trade deals, but the present situation isn’t yet about moving forward, simply protecting what we already have.

One glimmer of hope may be the frozen food industry that, if exporting to the EU, would be unable to use imported US chicken in its products. This would ensure at least one market for British poultry farmers that wouldn't be at the mercy of depressed prices, resulting from a rushed trade deal cobbled together as an example of how well Britain can thrive outside the EU. 

An indication of quite how far outside the bloc some Brexiteers are aiming comes from Foreign Secretary Boris Johnson's current "charm" offensive in Australasia. While simultaneously managing to offend Glaswegians, BoJo reaffirmed trading links with the region. Exports to New Zealand are currently worth approximately £1.25bn, with motor vehicles topping the list. Making the return trip, lamb and wine are the biggest imports, so it’s unlikely a robust trade deal in the South Pacific is going to radically improve British farmers’ lives. The same is true of their neighbours – Australia’s imports from Britain are topped by machinery and transport equipment (59 per cent of the total) and manufactured goods (26 per cent). 

Clearly keeping those trade corridors open is important, but it is hard to believe Brexit will provide a much-needed boon for British agriculture through the creation of thus far blocked export channels. Australia and New Zealand don’t need our beef, dairy or poultry. We need theirs.

Long haul exports and imports themselves also pose a bigger, longer term threat to food security through their impact on the environment. While beef and dairy farming is a large contributor to greenhouse gases, good stock management can also help remove atmospheric carbon dioxide. Jet engines cannot, and Britain’s skies are already close to maximum occupancy, with careful planning required to ensure appropriate growth.

Read more: Stephen Bush on why the chlorine chicken row is only the beginning

The global food production genie is out of the bottle, it won’t go back in – nor should it. Global food security relies on diversity, and countries working and trading together. But this needs to be balanced with sustainability – both in terms of supply and the environment. We will never return to the days of all local produce and allotments, but there is a happy medium between freeganism and shipping food produce halfway around the world to prove a point to Michel Barnier. 

If shoppers want a dragon fruit, it will have to be flown in. If they want a chicken, it can be produced down the road. If they want a chlorinated chicken – well, who does?