Subscribe to our free daily newsletters
. Earth Science News .

Subscribe to our free daily newsletters

The origins of abiotic species
by Staff Writers
Groningen, Netherlands (SPX) Jan 06, 2016

File image.

How can life originate from a lifeless chemical soup? This question has puzzled scientists since Darwin's 'Origin of species'. University of Groningen chemistry professor Sijbren Otto studies 'chemical evolution' to see if self-organization and autocatalysis will provide the answer. His research group previously developed self-replicating molecules - molecules that can make copies of themselves - and have now observed diversification in replicator mutants.

They found that if you start with one ancestral set of replicator mutants, a second set will branch off spontaneously. This means that ecological diversity as encountered in biology may well have its roots at the molecular level. The results were published on Jan. 4, 2016, in Nature Chemistry.

Life must have started at some point, but how remains a mystery. Charles Darwin himself speculated in a letter to Joseph Hooker in 1871: 'But if (and oh what a big if) we could conceive in some warm little pond with all sorts of ammonia and phosphoric salts, - light, heat, electricity and c. present, that a protein compound was chemically formed, ready to undergo still more complex changes, at the present day such matter wd be instantly devoured, or absorbed, which would not have been the case before living creatures were formed.'

It is impossible to know how life on Earth really started, but that doesn't stop scientists from trying to find out how it could have started. This is not just a matter of curiosity. The processes involved include autocatalysis (where molecules promote the formation of copies of themselves) and self-organization (where molecules spontaneously organize themselves into higher-order structures) which are important concepts in such fields as materials science.

Otto has been working on chemical evolution for several years now. 'It started with a chance discovery', he explains. 'We found some small peptides that could arrange themselves into rings, which could then form stacks.'

Once a stack began to form, it would continue to grow and would then multiply by breaking into two smaller stacks. These would both grow and break again, and so on. The stacks also stimulated the formation of the rings from which they are composed. The stacks and rings are called 'replicators', as they are able to make copies of themselves.

Jan Sadownik, a postdoc in the Otto group, discovered that if you offer the replicators two different types (A and B) of building blocks ('food') they will make copies of themselves. He observed the emergence of a set of replicator mutants that specialized in food A, but also incorporated some B. The rings mainly comprised the A building blocks, with just a few B's.

Some days later Sadownik saw a second set of mutants emerge that specialized in food B, but also tolerated some A. This second set proved to be a descendant of the first set, which meant there was an ancestral relationship between the sets.

This is very similar to how new species form from existing ones during biological evolution, except that this process of species formation does not involve full-fledged biological organisms, but occurs instead at the molecular level.

Molecular speciation
Looking at the molecular 'speciation' process in more detail allowed the researchers to identify specific mutants within the first set of replicators that were responsible for the generation of the second set.

They had therefore established the mechanism by which replicator 'species' form with unprecedented molecular-level detail. The spontaneous diversification of replicating molecules into distinct sets may well have been the first step in a long process that has led to the stunning ecological diversity that we see all around us today.

This shows how new 'species' can emerge through chemical evolution. Otto explains, 'Of course, the term speciation should only be used when referring to sexually reproducing organisms, but our work shows much the same patterns.' The exciting part, says Otto, is that 'we start with no replicators, but see first one type emerge and then after a while, another. That is certainly most significant!'

The next step is to introduce death. This can be done by feeding the system a constant flow of building blocks, while draining the contents of the reaction vessel. Replicators can only survive in this system when their growth rate exceeds the removal rate.

'We could then seed such a system with one set of replicator mutants, and then change the environment, for example by adding another solvent. This would change the fitness of the various replicator mutants and shift the population of mutants towards those that are best at replicating in the new environment.'

The result would be a form of natural selection that Darwin would recognize. 'We're not the only ones to be really excited about these experiments - the evolutionary biologist I've consulted is too.'

Reference: Jan W. Sadownik, Elio Mattia, Piotr Nowak and Sijbren Otto: Diversification of self-replicating molecules. Nature Chemistry, Advanced Online Publication Jan. 4, 2016. An 'explanimation' video on chemical evolution research by the Otto group is available on YouTube.

Thanks for being here;
We need your help. The SpaceDaily news network continues to grow but revenues have never been harder to maintain.

With the rise of Ad Blockers, and Facebook - our traditional revenue sources via quality network advertising continues to decline. And unlike so many other news sites, we don't have a paywall - with those annoying usernames and passwords.

Our news coverage takes time and effort to publish 365 days a year.

If you find our news sites informative and useful then please consider becoming a regular supporter or for now make a one off contribution.

SpaceDaily Contributor
$5 Billed Once

credit card or paypal
SpaceDaily Monthly Supporter
$5 Billed Monthly

paypal only


Related Links
University of Groningen
Darwin Today At

Comment on this article via your Facebook, Yahoo, AOL, Hotmail login.

Share this article via these popular social media networks DiggDigg RedditReddit GoogleGoogle

Previous Report
Wolf hunting begins in central Sweden
Stockholm (AFP) Jan 2, 2016
Hunters in central Sweden killed a wolf on Saturday as they began an authorized cull of the predators that has been clouded by legal uncertainty. "Our staff will inspect it, weigh and take samples. The body will then be sent to the National Veterinary Institute," Jonas Bergman, a conservationist at the county administrative board told the newspaper Sodre Dalarnes Tidning. The animal was ... read more

Obama set to hold town hall meeting on gun control

Natural catastrophe losses total $90 bn in 2015: Munich Re

Bus passengers airlifted as Scotland bears floods brunt

Britain's floods: causes, costs and consequences

Chameleons deliver powerful tongue-lashing

UCLA researchers create exceptionally strong and lightweight new metal

Coulomb blockade in organic conductors found, a world first

Adjustable adhesion power

After delay, rehabilated Cape Cod turtles arrive in Florida

River ecosystems show 'incredible' initial recovery after dam removal

Reducing CO2 footprint of desal crucial to achieving water sustainability

Heatwaves, drought may curb global power output: study

Meltwater from the Greenland ice sheet releasing faster

Antarctic sea ice melt released carbon from oceans as ice age ended

Climate change altering Greenland ice sheet and accelerating sea level rise

Large and increasing methane emissions from northern lakes

Restoring natural habitats across farms will boost CO2 sinks

Manure applications elevate nitrogen accumulation and loss

The billion dollar game of strategy: The effect of farmers' decisions on pest control

China's COFCO to buy agri-arm of top Asian trader

Body recovered from river as UK reels from storms

Traces of Icelandic volcanoes in a northeastern German lake

Hundreds evacuated as cyclone slams into Tonga

Search for more victims as deadly US floods stress levees

Mali extends state of emergency until March 31

Mali pro-govt armed group accuses France of killing 4 fighters

Malawi suspends 63 civil servants over stolen US funds

Expanded use of yuan to help revive Zimbabwe's economy: Mugabe

Carnegie Mellon develops new method for analyzing synaptic density

Why the real King Kong became extinct

Genomes of early Irish settlers sequenced

Same growth rate for farming, non-farming prehistoric people

Memory Foam Mattress Review
Newsletters :: SpaceDaily :: SpaceWar :: TerraDaily :: Energy Daily
XML Feeds :: Space News :: Earth News :: War News :: Solar Energy News

The content herein, unless otherwise known to be public domain, are Copyright 1995-2017 - Space Media Network. All websites are published in Australia and are solely subject to Australian law and governed by Fair Use principals for news reporting and research purposes. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA news reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. All articles labeled "by Staff Writers" include reports supplied to Space Media Network by industry news wires, PR agencies, corporate press officers and the like. Such articles are individually curated and edited by Space Media Network staff on the basis of the report's information value to our industry and professional readership. Advertising does not imply endorsement, agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. Privacy Statement