Origins of Monogamy Cause Evolutionary Paradigm Breakup

Origins of Monogamy Cause Evolutionary Paradigm Breakup

Gregg Allman fronted the Allman Brothers Band for over 40 years until his death in 2017 at the age of 69. Writer Mark Binelli described Allman’s voice as “a beautifully scarred blues howl, old beyond its years.”1

A rock legend who helped pioneer southern rock, Allman was as well known for his chaotic, dysfunctional personal life as for his accomplishments as a musician. Allman struggled with drug abuse and addiction. He was also married six times, with each marriage ending in divorce and, at times, in a public spectacle.

In a 2009 interview with Binelli for Rolling Stone, Allman reflected on his failed marriages: “To tell you the truth, it’s my sixth marriage—I’m starting to think it’s me.”2

Allman isn’t the only one to have trouble with marriage. As it turns out, so do evolutionary biologists—but for different reasons than Greg Allman.

To be more exact, evolutionary biologists have made an unexpected discovery about the evolutionary origin of monogamy (a single mate for at least a season) in animals—an insight that raises questions about the evolutionary explanation. Based on recent work headed by a large research team of investigators from the University of Texas (UT), Austin, it looks like monogamy arose independently, multiple times, in animals. And these origin events were driven, in each instance, by the same genetic changes.3

In my view, this remarkable example of evolutionary convergence highlights one of the many limitations of evolutionary theory. It also contributes to my skepticism (and that of other intelligent design proponents/creationists) about the central claim of the evolutionary paradigm; namely, the origin, design, history, and diversity of life can be fully explained by evolutionary mechanisms.

At the same time, the independent origins of monogamy—driven by the same genetic changes—(as well as other examples of convergence) find a ready explanation within a creation model framework.

Historical Contingency

To appreciate why I believe this discovery is problematic for the evolutionary paradigm, it is necessary to consider the nature of evolutionary mechanisms. According to the evolutionary biologist Stephen Jay Gould (1941–2002), evolutionary transformations occur in a historically contingent manner.4 This means that the evolutionary process consists of an extended sequence of unpredictable, chance events. If any of these events were altered, it would send evolution down a different trajectory.

To help clarify this concept, Gould used the metaphor of “replaying life’s tape.” If one were to push the rewind button, erase life’s history, and then let the tape run again, the results would be completely different each time. In other words, the evolutionary process should not repeat itself. And rarely should it arrive at the same end point.

Gould based the concept of historical contingency on his understanding of the mechanisms that drive evolutionary change. Since the time of Gould’s original description of historical contingency, several studies have affirmed his view. (For descriptions of some representative studies, see the articles listed in the Resources section.) In other words, researchers have experimentally shown that the evolutionary process is, indeed, historically contingent.

A Failed Prediction of the Evolutionary Paradigm

Given historical contingency, it seems unlikely that distinct evolutionary pathways would lead to identical or nearly identical outcomes. Yet, when viewed from an evolutionary standpoint, it appears as if repeated evolutionary outcomes are a common occurrence throughout life’s history. This phenomenon—referred to as convergence—is widespread. Evolutionary biologists Simon Conway Morris and George McGhee point out in their respective books, Life’s Solution and Convergent Evolution, that identical evolutionary outcomes are a characteristic feature of the biological realm.5 Scientists see these repeated outcomes at the ecological, organismal, biochemical, and genetic levels. In fact, in my book The Cell’s Design, I describe 100 examples of convergence at the biochemical level.

In other words, biologists have made two contradictory observations within the evolutionary framework: (1) evolutionary processes are historically contingent and (2) evolutionary convergence is widespread. Since the publication of The Cell’s Design, many new examples of convergence have been unearthed, including the recent origin of monogamy discovery.

Convergent Origins of Monogamy

Working within the framework of the evolutionary paradigm, the UT research team sought to understand the evolutionary transition to monogamy. To achieve this insight, they compared the gene expression profiles in the neural tissues of reproductive males for closely related pairs of species, with one species displaying monogamous behavior and the other nonmonogamous reproduction.

The species pairs spanned the major vertebrate groups and included mice, voles, songbirds, frogs, and cichlids. From an evolutionary perspective, these organisms would have shared a common ancestor 450 million years ago.

Monogamous behavior is remarkably complex. It involves the formation of bonds between males and females, care of offspring by both parents, and increased territorial defense. Yet, the researchers discovered that in each instance of monogamy the gene expression profiles in the neural tissues of the monogamous species were identical and distinct from the gene expression patterns for their nonmonogamous counterparts. Specifically, they observed the same differences in gene expression for the same 24 genes. Interestingly, genes that played a role in neural development, cell-cell signaling, synaptic activity, learning and memory, and cognitive function displayed enhanced gene expression. Genes involved in gene transcription and AMPA receptor regulation were down-regulated.

So, how do the researchers account for this spectacular example of convergence? They conclude that a “universal transcriptomic mechanism” exists for monogamy and speculate that the gene modules needed for monogamous behavior already existed in the last common ancestor of vertebrates. When needed, these modules were independently recruited at different times in evolutionary history to yield monogamous species.

Yet, given the number of genes involved and the specific changes in gene expression needed to produce the complex behavior associated with monogamous reproduction, it seems unlikely that this transformation would happen a single time, let alone multiple times, in the exact same way. In fact, Rebecca Young, the lead author of the journal article detailing the UT research team’s work, notes that “Most people wouldn’t expect that across 450 million years, transitions to such complex behaviors would happen the same way every time.”6

So, is there another way to explain convergence?

Convergence and the Case for a Creator

Prior to Darwin (1809–1882), biologists referred to shared biological features found in organisms that cluster into disparate biological groups as analogies. (In an evolutionary framework, analogies are referred to as evolutionary convergences.) They viewed analogous systems as designs conceived by the Creator that were then physically manifested in the biological realm and distributed among unrelated organisms.

In light of this historical precedence, I interpret convergent features (analogies) as the handiwork of a Divine mind. The repeated origins of biological features equate to the repeated creations by an intelligent Agent who employs a common set of solutions to address a common set of problems facing unrelated organisms.

Thus, the idea of monogamous convergence seems to divorce itself from the evolutionary framework, but it makes for a solid marriage in a creation model framework.

Resources

Endnotes
  1. Mark Binelli, “Gregg Allman: The Lost Brother,” Rolling Stone, no. 1082/1083 (July 9–23, 2009), https://www.rollingstone.com/music/music-features/gregg-allman-the-lost-brother-108623/.
  2. Binelli, “Gregg Allman: The Lost Brother.”
  3. Rebecca L. Young et al., “Conserved Transcriptomic Profiles underpin Monogamy across Vertebrates,” Proceedings of the National Academy of Sciences, USA 116, no. 4 (January 22, 2019): 1331–36, doi:10.1073/pnas.1813775116.
  4. Stephen Jay Gould, Wonderful Life: The Burgess Shale and the Nature of History (New York: W. W. Norton & Company, 1990).
  5. Simon Conway Morris, Life’s Solution: Inevitable Humans in a Lonely Universe (New York: Cambridge University Press, 2003); George McGhee, Convergent Evolution: Limited Forms Most Beautiful (Cambridge, MA: MIT Press, 2011).
  6. University of Texas at Austin, “Evolution Used Same Genetic Formula to Turn Animals Monogamous,” ScienceDaily (January 7, 2019), www.sciencedaily.com/releases/2019/01/1901071507.htm.