Behavioral Evolution in the Red Fire Ant

Behavioral Evolution in the Red Fire Ant

The behavioral evolution in the red fire ant species with the two different types of colonies, one with a single queen and one with multiple queens, have long puzzled biologists. An invisible border seems to exist between the two. Queen ants happening to wander between colonies are quickly destroyed by the male ants. To understand what evolutionary mechanisms might be at play, molecular scientists have recently turned to the genome.

At Queen Mary University of London, a team of biochemists led by Rodrigo Pracana (pictured below) sequenced the whole genome in both colony types to examine the genetic difference between the two types of colonies – SB and Sb. Surprisingly, rather than finding “slight, successive changes” as predicted by Charles Darwin’s theory of evolution, they discovered two the genes to be “highly divergent” from each other.

Solenopsis invicta Chromosomes

The two colonies are considered genetic variants within the same species known as Solenopsis invicta. Of the red ant’s 16 chromosomes containing more than 500 genes, these variants have been demonstrated to determine whether the colony will have only one or up to dozens of queens in the colony.

Of interest, SB and Sb share a similar pair of sex chromosomes, a supergene region known as “social chromosomes” and only small genetic differences between these were predicted since natural selection only acts by “finely graduate… slight, successive changes.”

Evolution through gradual steps over long periods of time is the foundation of Charles Darwin’s theory. In describing the actions of natural selection, in The Origin of Species (1859) Darwin selected the phrase “Natura non-facit saltum’’ – a Latin phrase meaning that nature makes no leaps.

In applying Darwin’s theory, modern scientists expected to discover evidence of natural selection advancing biological evolution incrementally leaving a molecular “evolutionary strata” – analogous to geological strata developing uniformly over long periods of time.

However, in Pracana’s paper entitled “The fire ant social chromosome supergene variant Sb shows low diversity but high divergence from SB” published in the journal of Molecular Ecology (2017), the team unexpectedly discovered that within these “social chromosomes” of eight SB males and eight Sb males –

“We find no evidence of ‘evolutionary strata’ with different levels of divergence.”

The long-anticipated evidence for evolution in the red fire ant genome sequence between colonies were missing. In a February 20, 2016 interview published on entitled “Scientists explore the evolution of a ‘social supergene’ in the red fire ant,” Yannick Wurm (pictured left), the corresponding research team member, further highlighted the dilemma –

“We found that the two versions of the chromosome differ homogeneously over the entire length of the supergene.”

In the place of Darwin’s “finely graduate… slight, successive changes,” SB and Sb chromosomes differ completely with no transitional links between SB and Sb. Where evidence for molecular evolution was predicted by the theory, none could be detected.

Rather than demonstrating the predictive power of Darwin’s theory, evidence from the red fire ant genome demonstrates that Darwin was simply wrong. This evidence, however, was not available prior to the genomic revolution.

Centenary Celebration

Predicting the effect of a yet unknown genomic revolution on Darwin’s theory during the mid-twentieth century was only science fiction.

Gaining increasing confidence with a theory of evolution the who’s who in the evolution industry, Julian Huxley, Ernst Mayr, George Gaylord Simpson, Louis Leaky, Theodosius Dobzhansky, G. Ledyard Stebbins, Hermann J. Muller, Edmond B. Ford, and Conrad. H. Waddington, proudly paraded their rising star at the Darwin Centenary Celebration (pictured right) held at the University of Chicago in 1959.

Julian Huxley, the grandson of “Darwin’s Bulldog,” declared that evolution “is simply is not just a theory any longer. It is a fact, like the fact that the earth goes around the sun.”

The key driving force of the theory of evolution, then known as the modern synthesis, had been championed by H. J. Muller – a theory that merged genetic mutations with Darwin’s natural selection. In a Scientific American (1928) article entitled “New Discovery Speeds Up Evolution,” Muller predicted –

“Evolutionary changes, or mutations, can be produced 150 times as fast by the use of X-rays as they can be by ordinary processes of nature.”

Genomic Revolution

By the late twentieth century, however, Muller’s X-rayed fruit flies were still fruit flies – if not killed by genetic mutations and centenary celebrants began noticing problems – expressing doubts.

Today, the US Center for Disease Control (CDC) lists hundreds of human diseases caused by genetic mutations. Not one genetic mutation is known to be beneficial. As red fire ant demonstrates, the evolution industry is desperately searching for a new driver and theory of evolution.

The genomic revolution is driving the once popular modern synthesis model into extinction – and increasingly replaced by even more abstract epigenetic models of evolution.

Natural Selection Erosion

Critics of Darwin’s natural selection theory during the twentieth century were many – even within the halls of the evolution industry. Darwin’s theory “may be little more than a truism to state that the individuals that are best adapted to survive have a better chance of surviving than those not so well adapted to survive,” according to Thomas Huxley.

Conrad H. Waddington (pictured right) of Edinburgh University, agrees with Huxley –

“There, you do come to what is, in effect, a vacuous statement: Natural selection is that some things leave more off spring than others; and you ask, which leave more off spring than others; and it is those that leave more off spring; and there is nothing more to it than that.”

Salvage Mission

Since the evidence from molecular biology to salvage the theory of evolution has failed to materialize, as has the fossil record and embryology, this past November, in an effort to salvage a united pathway to a new theory of evolution, the Royal Society convened a conference of leading evolutionary scientists entitled “New trends in evolutionary biology: biological, philosophical and social science perspectives.” According to the Royal Society,

“Developments in evolutionary biology and adjacent fields have produced calls for revision of the standard theory of evolution, although the issues involved remain hotly contested.”

What new theory emerged? None. A salvage theory for the evolution industry is increasingly emerging as an illusively distant dream. Early during the convention, Kevin Laland, one of the event organizers, made the best of the inescapable tension –

“I think it’s going quite well. It hasn’t gone to fisticuffs yet.”


Despite a flood of challenges since the publication of The Origin of Species with more than 150 years of unprecedented scientific efforts in the history of mankind to prove otherwise, the evidence in nature is increasingly best explainable by the Genesis record written by Moses.

In the perspective of Ernest Rutherford (1871–1937), the father of nuclear physics,

“That which is not measurable is not science.”

Since the evidence could not be measurable, behavioral evolution in the red fire ant evolution belongs in the realm of science fiction.

Evolution, once a theory in crisis, is now in crisis without even a cohesive unifying theory.

Biological evolution exists only as a philosophy, not a science.


One Response to “Behavioral Evolution in the Red Fire Ant”

  • The are some notable things about this article about fire ant social behavior. The authors in the original article ( note that the 500 gene region controlling the ant behavior was homogeneously different between the two groups of ants, suggesting that one mutation event led to the difference rather that multiple progressive mutations. They say that probably multiple gene differences in that chromosome region of 500 genes is responsible for the behavior difference. This is a curious inconsistency. They are sequencing DNA, so they should know the exact gene differences between the groups, not such a vague generalization. And what follows is how a single mutation event could lead to those multiple gene differences? They go on to state that many of the mutations in the region lead to unfavorable consequences to the multiple queen ant behavior group. They then opine that the survival advantage of having multiple queens must be outweighing the unfavorable consequences of the mutations. So what we have here is a loss of function by mutation (the unfavorable consequences) leading to a serendipitous gain by the multiple queen behavior. The is similar to the sickle cell trait in humans serendipitously leading to a survival advantage against malaria. In summary, there is NO evolution, but instead a loss of information leading to a secondary survival advantage. The fire ant is still a fire ant.

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Darwin, Then and Now is a journey through the most amazing story in the history of science - the history of evolution. The book encapsulates who Darwin was, what he said, and what scientists have discovered since the publication of The Origin of Species in 1859.

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