Fossils show 'chemistry of life'

30 June 2011 Last updated at 19:01 By Victoria Gill Science reporter, BBC Nature The study revealed the chemistry preserved in the 120 million-year-old fossilised bird The pigments preserved in fossils, including a 120 million-year-old bird, have been revealed using X-rays.

A team, led by scientists from the University of Manchester, UK, scanned the beautifully preserved fossils.

Their study, published in the journal Science, revealed the chemical fingerprint of pigments that once tinted the ancient bird's feathers.

Manchester palaeontologist Phil Manning described the discovery as an insight into "the chemistry of life itself".

As well as the colour patterns of ancient creatures, pigments reveal fundamental clues about the chemical reactions that took place in their bodies, and the food the creatures ate that fuelled those reactions.

The study allowed the researchers to paint a monochrome picture of the ancient bird

Dr Manning, his Manchester colleague Roy Wogelius and Uwe Bergmann from the SLAC National Accelerator Laboratory in California, led the international team. They used a powerful X-ray source called a synchrotron, which uncovered metals within the ancient fossilised feathers.

"These trace metals, specifically copper, is a [marker] for a dark pigment called eumelanin," explained Dr Wogelius. This X-ray technique was so sensitive that it was able to show that each molecule of copper it detected was being tugged and squashed into a particular shape because it was bound within a eumelanin molecule.

See the dark

The X-rays acted as probes, detecting the individual chemical building blocks that make up the fossil. When the rays hit the fossil, the signal that bounces back depends on the shape and size of each molecule, and how it is being subtly influenced by the chemicals surrounding it.

The team used this powerful probe to scan fossilised remains of two ancient birds: 110 million-year-old Gansus yumenensis, the oldest example of a modern bird in the fossil record, and 120 million-year-old Confuciusornis sanctus, the earliest beaked bird.

Copper (light-coloured areas) revealed the dark pigments on the ancient bird's neck and body

This revealed, not only that the dark pigment molecules were an intrinsic part of the chemical matrix of the birds' feathers, but that they were perfectly preserved for up to 120 million years. This allowed the researchers to paint a monochrome picture of both ancient creatures.

Dr Wogelius said: "[Eumelanin] controls the dark and light patterns of an animal, so for Confuciusornis sanctus, for example, we can see that its body and the neck were black and its wings were patchy.

"For years people had been looking at these fossils thinking that the feathers were just impressions. We showed that they have chemistry."

Previous attempts to diagnose the colour of long extinct animals focused on pigment "containers" in feathers known as melanosomes. But these biological paint pots, Dr Manning explained, do not survive well in ancient fossils.

"But the pigments they once contained do, courtesy of their copper heart - even after the melanosome containing them has been destroyed," he told BBC Nature.

The new technique will allow scientists to study the chemistry of more fossils, without having to damage them by removing samples. For many fossils, this is an important consideration; an Archaeopteryx specimen the group studied last year has been valued at an estimated $6 million (?3.75 million).

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The potential for this technique to gently un-pick the chemistry of long extinct species is quite breathtaking”

End Quote Phil Manning University of Manchester Dr Phil Manning said that the findings showed the "potential for unlocking the prehistoric colour palette", but that they also contained more fundamental clues about ancient life.

"This offers insight to the [biochemistry] that governed life tens or even hundreds of millions years ago," he told BBC Nature.

Since metals, including zinc and copper, form part of many animals' diets, so mapping them in fossils could shed light on what the animals fed on 100 million years ago.

And since one of the key roles of pigmentation is camouflage, pigmentation could tell us more about the world around the animal and what it was trying to blend into.

Dr Manning said: "The potential for this technique to gently un-pick the chemistry of long extinct species is quite breathtaking."

"We can even start treating the fossil record as a long-term experiment for burying organic compounds in different environments and then studying what happens to them through deep geological time," he said.

The technique allows complete fossils to be studied

"So it could help us understand what happens when you bury something like biowaste in the ground.

"We could really understand what happens to something when its buried for 120 million years; this goes way beyond palaeontology."

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Arctic fossils

24 May 2011 Last updated at 14:35 GMT The pristine waters off Greenland are targets for a new oil and gas drive There's something of a new sunrise in the Arctic this year.

And I'm not just talking about the spectacularly beautiful event that begins every spring day.

The Arctic Sunrise is a ship belonging to Greenpeace, which has done battle in many corners of the world against most things that the organisation detests.

Now, it is steaming close to the Greenland coast, engaged in opposition to a relatively new issue: deepwater drilling for oil and gas in these remote, chilled waters.

Confrontations here are likely to be a regular feature in the coming months; this is a major new frontier.

Together with its sister ship Esperanza, the Arctic Sunrise has just made contact with the Leiv Eiriksson, a rig that will shortly begin its scheduled exploration programme for the summer.

The rig is being escorted by a 120-metre Danish warship.

As a quasi-colonial power, Denmark is responsible still for policing Greenlandic waters, and was presumably called up because Greenpeace activists have already boarded exploration rigs once this year, and wouldn't have ventured into the Arctic unless they had something more planned.

According to the US Geological Survey, almost a quarter of the world's undiscovered but potentially exploitable oil and gas reserves may lie beneath the Arctic seabed.

And as summer ice cover shrinks, opportunities to exploit these fields are opening up.

Greenpeace - and other environmental groups - are calling for a halt to these projects, essentially for two reasons.

Firstly, last year's Gulf of Mexico disaster illustrated just how badly wrong things can go on a deepwater rig - and the social and environmental costs will be counted for many years to come.

Basic science tells you that in colder water, oil products are going to remain intact for much longer before being broken down. Rescue and clean-up operations will be more difficult in the roiling Arctic than in the relative calm of the gulf.

The second reason is that in an era when virtually all governments say they're committed to reducing greenhouse gas emissions, how is it sensible to be investing money in finding new stocks of fossil fuels to exploit?

The most important governments in the new Arctic oil race - Canada, Russia and the US - are, co-incidentally or otherwise, among the least keen to see a new global treaty limiting greenhouse gas emissions.

As Wikileaks revealed earlier this month, far from trying to restrain exploration, leaders have actively been discussing how to "carve up" the region's resources between them.

Greenland raises a particular issue, with its recent successful bid for greater independence from Denmark being partially driven by the huge revenues oil and gas exploitation could bring.

Greenpeace has been doing a little revealing, too.

Actions against Arctic rigs are set to be a regular occurrence in the coming months

It's publishing UK government documents, obtained via Freedom of Information (FoI) requests, that indicate a level of alarm about the damage that could result from a spill.

"It is difficult to get assistance in case of pollution problems in such areas, and near impossible to make good damage caused," reads a message sent from one official to another - their identities redacted.

The UK doesn't have any territorial claims north of the Arctic Circle; but UK-based companies such as Cairn Energy, which is contracted to do the Greenland exploration this summer, are active players.

"The rapid pace of both global warming and extraction technological advance means that the world's last frontier for petroleum may be open for exploration much sooner than expected just a few years ahead," another of the internal UK documents notes.

The writer ponders: "Can the UK risk losing business opportunities for the sake of environmental protection?"

The memo implies that different arms of the UK government are not having the most constructive of conversations with each other.

Its writer asks: "If in the Arctic High North we do not seek the resources to satisfy growing global energy demand, it is unclear where else these resources might be found."

Yet the UK's official line on this is that the resources can and should be found in the wind, in waves and tides, in sunlight, and the power of the atom.

Which of those assessments is the more honest is a question to mull.

Whatever the concerns, Arctic oil and gas exploration looks set for a big expansion.

Canada is forging ahead; so are Russia and Norway. Greenland clearly wants to join the race, while the US is likely to grant new exploration rights once operators have satisfied authorities that they have learned lessons from the gulf leak.

Can environmental groups do enough to stop it - especially when governments appear to have decided already that the environmental risks are worth taking in return for a continuing supply of black gold?

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