Survival of the Fittest Theory Gets a Boost

Posted July 8th, 2011 at 7:32 pm (UTC-4)

Do certain species survive at the expense of others? The question of competition between the species was at the heart of a premise first explored by Charles Darwin in 1859. A new study lends further support to this aspect of Darwin’s still-controversial theory of natural selection.

Darwin’s  “On the Origin of Species by Means of Natural Selection” outlined a revolutionary approach which would eventually become known as evolutionary biology.  Today, more than a century later, scientists continue to try to either prove or disprove Darwin’s theories.

One of Darwin’s hypotheses explored the role  competition played in determining the survival of a species.  A recently released study led by Lin Jiang at Georgia Institute of Biology – otherwise known as Georgia Tech – supports this theory.

Although most scientists already tend to accept Darwin’s premise, this new study presents the strongest direct experimental evidence yet to support its validity.

Dr. Jiang’s team chose to study 10 common species of the ciliated protist – or protozoa microrganisms – because of their ability to reproduce. This allowed the research team to examine the co-existence of the species over multiple generations in just a few weeks.

The research team conducted their experiments within specially constructed, artificial and simplified ecosystems called microcosms.

When left alone in a microcosm, all of the species survived until the end of the experiment. However, when two species were paired together, one dominated in more than half of the experiments, leading to the extinction of the other species.

The team found that extinction occurred faster and more often between the species of  microorganisms that were more closely related. Dr. Jiang says this aspect of the study supports Darwin’s theory, referred to as the phylogenetic limiting similarity hypothesis.

This hypothesis is just one of the many Darwin published in “The Origin of Species.”  It was through this book that Darwin introduced the scientific theory that populations evolve over the course of generations through a process of natural selection.

This weekend on the “Science World” radio program, Dr. Jiang explains this hypothesis and talks to us about his team’s research and what else they learned from their studies.

Listen to the interview here…

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Other stories we cover on the “Science World” radio program this week include:

Rick Pantaleo
Rick Pantaleo maintains the Science World blog and writes stories for VOA’s web and radio on a variety of science, technology and health topics. He also occasionally appears on various VOA programs to talk about the latest scientific news. Rick joined VOA in 1992 after a 20 year career in commercial broadcasting.

5 responses to “Survival of the Fittest Theory Gets a Boost”

  1. Wakeman says:

    Darwin’s still-controversial theory of natural selection? Get a grip, there is no controversy. No respectable scientist in the world doubts the validity of “natural selection” as a process through which evolution takes place. Random mutations sometimes produce favourable adaptations to the environment, which then provide a survival and (therefore) reproductive advantage. Genomic and phenomic change can also occur through “human selection,” as it has for many crops, and for example, breeds of dogs.

  2. JTK says:

    Too much pussyfooting around. Evolution is accepted, the debate is only around the specifics. Can VOA please rise to a higher standard than this?

  3. Alex says:

    Bizarre.. still controversial? This is not the 19th Century any more. Furthermore, when even the majority of Muslim Imams proselytising in the USA submit a publication in America that they finally agree Evolution occurs, and that the Vatican now agrees it occurs (my, how very noble of them all, the crashing weight of centuries of irrefutable evidence finally getting through their indoctrinated skulls, like finally pardoning Copernicus and Galileo)…then..

    Frankly who cares what the bronze age Middle Eastern superstitions think? They are hardly best qualified to comment on reality, are they? Look at the intolerance, and World Peace that they have given us, versus what Science has given the species?

    VOA, stick to the facts only, and less of the pandering to the extreme right wing religious nut-jobs. The editorial here could have handled this far simpler and achieved the same objective without your submissionist craven attempt to court the ill-educated indoctrinated in your poorly schooled country.

  4. I love all the replies to this post… but I’m kind of surprised and amused that so many wonder how Mr. Darwin’s theories are still controversial today.

    While still technically called a “theory” it’s hard to escape and really deny the evidence to its validity.

    But even in today’s “modern and sophisticated” era of scientific and technological advancements there are still many who wholly believe in the creationism scenario.

    Those who support this basis of life on earth don’t necessarily ascribe or believe in one religion or are only from certain parts of the world, but have varied religious beliefs and hail from all parts of the world.

    As the 150 Anniversary Darwin’s theories were to be commemorated in 2009, debate and controversy over these theories still continued.

    Check out this 2008 article from the New Scientist

    Or this 2007 article from the Pew Research Center

    The Oxford University Press Blog published this article this past April.

    While what many of us take as absolute there are still those, many even quite educated, who believe likewise or have their doubts.

    And those who say that VOA is “pandering” toward any one or particular group of people… I should refer you to what journalists at VOA must follow, by law, in doing their jobs – article #2 of the VOA Charter.

    2. VOA will represent America, not any single segment of American society, and will therefore present a balanced and comprehensive projection of significant American thought and institutions.

    Thanks so much for the comments! Keep them coming!

  5. Alex says:

    VOA, you also have a duty of care to the facts. Do you wish to state that there are many in America who think that the Earth is flat, and all the other American sourced conspiracy theories? Notably the flat Earther movement is a rather USA grouping of people, again, like Creationists, being largely launched, and driven from the USA. The old world created you, but also you became a repositary early on of every minority small scale nut-case superstition going, starting with the Puritans.

    Next up, Gravity.. only a theory..

    This article could have been written better, while still matching your Charter requirements – and the platform could have been used in such a way that the issues would be clear, and representative of both sides of view – i.e. those with belief and no evidence, and those with overwhelming, testable, provable, repeatable evidence, in any sphere of the sciences.

    A poor waste of a platform for educating those about the subject too, a missed opportunity of knowledge for good – in a country when a lot more rigour and education about science is a key concern given the shocking state of the economy, and the singular lack of innovation and scientific advances being made compared to the past.

    The problem starts in the poor education of Americans, with its poor standards of Science teaching across the board compared with other Nations and continues in the hand-wringing submissionism of its media.