Round Table Discussion on the Hologenome - Google+

The Bordenstein Lab is about to host a round table discussion on the hologenome. I will live blog it as well as host one of the live feed videos here. The original link to the Google + page, where we will announce future updates and discussions.

Only 12 min before the life feed begins on the hologenome.

10 am Time to start!!!

@ 10:0 we have 8 participants so far and 10 viewers... if you can't join the hangout, you can still participate in the chat

@ 10:09, it begins!

@ 10:10 What, who, and  why of the hologenome. Some of the terms are supper organism, holobiont. The idea that the hologenome is still controversial and is an important discussion to have so all areas of biological sciences.

@ 10:12 Is the holobiont/hologenome jargon?
is it any different then any other organism-interaction?

Mark Martin

10:18 AM

Thought: microbiome is clearly coevolved and specific. Winnowing from much more complex environmental community. Two sides of one coin.

@ 10:19 is the host really any different than a single additional organism that is part of a continuum?

@ 10:21 What is the experiment needed to validate or deny the hologenome?

@ 10:27 what does evolution see? are the interactions negative or positive or are the windows of evolution and selection not able to fit within the trajectory of microbiome-host interaction?

@ 10:34 perhaps functional genes are perhaps important role in who and what are present as a hologenome.

@10:41 Bordenstomics! the hologenome needs more metaomics to be able to answer some of these questions.

@ 10:47 is it necessary to call the microbes anything different then the environment? or is it because there is a biotic factor of the microbiome that separates it from the abiotic factors?

@ 10:50 how is a tapeworm different then the microbiome?

@ 10:54 is the hologenome a useful phrase for the body of knowledge we have now? The microbes are not individual players but interactions that compose the species that we describe.

@ 11:01 we are wrapping up the discussion. It will be saved and uploaded to youtube.

Overall the discussion went really well. I didn't get a chance to copy in some of the chatroom posts (not fully caffeinated yet). But there were some really great discussion point brought up overall. Including the fact that a species and its microbiome are integrated into eachothers' success.

To summarize, the biggest component of the hologenome discussion was how should we define the hologenome relative to our existing concepts of evolution, species, ecology, and microbial ecology. Is there a distinction between the microbiome in a host organism as part of the host, or is the host just part of the microbial community? Clearly the environment plays a role in establishing the taxonomic representation of the microbiome but is it limited by the host? How is it truly different than any-other organism-organism interaction? The field of clearly needs to conduct more scientific investigations of the hologenome concept before we can address these issues. There was a general consensus that the term 'holobiont' does describe the unit of selection, but how far that extends beyond microbe-host interactions is still controversial.

The hangout consisted of mostly pro-holobiont supporters but David Baltrus was a wonderful foil for counterpoints to the hologenome. Arguments that the hologenome could extend to parasites like tapeworms, pathogens, and domesticated plants, where would they fit into the definition? These are great points that are an important dialogue to the discussion. He laid out a few additional components in a great blog post about ecological epistasis.

In the end, we all agreed that the round table could go for a round two. In the mean time, watch out for falling coconuts, you don't want to end up a statistic. 

Of pop art and holobiont

'Nasonia' by Robert M. Brucker, 2013. A digital homage to Warhol's 'Marilyn' series of screen prints.

We recently published the major part of my thesis in the journal Science -- "The Hologenomic Basis of Speciation: Gut Bacteria Cause Hybrid Lethality in the Genus Nasonia."We were fortunate to be promoted to a Science Express article, which means that it is available online well before the final print, which should be around August-September (we don't have the final date yet). When we were in the process of submitting the final documents to the editor we included a few options for potential cover art. Although we may not be selected for the cover, the process did make me think about our work from an art history perspective.

It started when I called my mother, a retired high school art teacher. I asked her for recommendations for a visual way to represent the scientific story we were telling. She had come to my thesis defense, has heard me talk about my work, and has printed off my papers to put on their coffee table--she does not understand it all but she has a surface knowledge of what I do. After some thought, she recommended that I try imitating an Andy Warhol. I thanked her for her advice, but inside I felt that she did not quite understand what it was I was looking for in a concept image. I wanted something that could depict the complexity and the universality of the hologenome--the idea that the genome and the microbiome are linked in the evolution of any animal species. I could not see how nauseously vibrant screen prints was relevant. However, sleeping on it always helps me. The next morning, as I was brushing my teeth, it hit me--my mother was on to a deeper connection with my science than I realized. You see, Andy Warhol is one of the most iconic, great american artists, whom pushed the conventional boundaries of art into the familiar and ordinary. His work was pivotal to the Pop Art movement of mid 1950's-60's America. Much like the pop art movement, the hologenome theory is controversial within the field of evolution, yet it is easily connectable to our understanding of what makes a species.

For a little perspective, the pop art movement reveled in an anti-traditional and anti-esthetic means to present familiar everyday objects, events, and celebrities. Artists of this movement imitated the styles of commercial art and mass media to push away from the unfamiliar and almost-elitist abstract expressionism movement (artists such as Jackson Pollock). The tradition of art before the pop art movement set the artist and the concept behind the artists work as a superior form of experiential being, an expression of human emotion that was meant only to be reviled through exploration of the work. Pop art on the other hand was obvious, mashing every day objects and the emotions attached to those within the artist's piece. This push towards the common connection between the art and the viewer challenged the definition of what Art is. Since Art can now include the common and the surreal, connect emotion to the mundane, then Art can be almost anything. For example, Warhol's soup can prints represent the disposable, mass-produced American life of the era, but also something that has a life of its own.

The hologenome theory of evolution includes the microbial organisms as an extension of the host's genes. This theory is a concept that challenges the definition of a species, pushing it beyond the boundaries of the cell wall. The traditional understanding of a species are the gene-gene interactions between DNA and/or cytoplasm (mitochondria and chloroplasts) that limit the reproductive success between species. This has been the dogma of evolutionary biology for nearly a century, and with good reason. Gene-gene interactions likely the primary mechanisms that isolate species; however, there is a greater genetic diversity within a species if one includes the genes found in the microbiome. The expansion of available genetic diversity within a species provides new opportunities for selection to drive speciation. The presence of microorganisms is common and required for the health and development of the host organism they live in/on.

We take for granted the omnipresence of the microbes around us. Their life is as much apart of our own existence, but yet, until the hologenome theory, they played little part in our understanding of species. The same is true for our dependancies on consumerism and the celebrated individual as an unavoidable part the modern society but was not a part of our artistic dialogue until the pop art movement. Bacteria are often considered part of the environment, and any influence they have on a species is no different then any other organism-organism interaction, like say a predator and prey. But because it is impossible to have a naturally occurring organism without any microbiome, bacteria are essential to the existence of that species. Pop art parallels this, ordinary objects and pop culture references where not considered high art because they were part of everyday society, but yet art is a reflection of our society--neither exists with out each other. Our microbes are as much part of our identity as a species as Marilyn Monroe. The art and beauty of living surrounds us, though in mass produced quantities it represents what we are and where we are going.

For more information on the hologenome topic:
This video by Richard Jefferson on the definitions of the hologenome
A review of the hologenome thory by Eugene Rosenberg, Gil Sharon, and Ilana Zilber- Rosenberg.
Our review article, Speciation by Symbiosis giving examples as to how bacteria influence barriers between species (pdf).
Seth Bordenstein has written/vloged about the hologenome and speciation by symbiosis.