About this Blog:

This blog is a source of information for the general public on the science behind algae biofuel, algae for energy, algae for carbon sequestration and algae for remediation.

Wednesday, July 20, 2011

Chronologically impaired: how to know what to make of the term "ancient algae"

Its now been a really really long time since I have written. This is mostly due to the time constraints of a researcher who is doing many things at once. I have been teaching which has been wonderful but time consuming, I have been writing papers which is necessary but all consuming, and I have been writing proposals, coordinating workshops, starting new projects...etc...

But every once in a while an article comes along to remind me why I started this blog in the first place: to explain what the heck some of these reporters and business types mean when they throw scientific words around with algae. Today I read an article that was so misleading (in my opinion) that I was compelled to write. This article in ScienceDaily is trying to sensationalize an idea, while mangling the concept. They are reporting on this article published this week in the Proceedings of the National Academies of Science.

When people talk about ancient algae, my ears perk up. My dissertation research was on how to use geological evidence (fossils and preserved organic molecules) to tell the early evolutionary history of algae. I also attacked this problem using genes and making phylogenetic trees . One of my motivations for my research is the way people over-simplify the geologic record and want to take small pieces of evidence and make big stories out of them. That makes things accessible to people who's mindes aren't really built to think in geologic time - think about what 10 years means in terms of your life, or 100 years or 1000 years and then try to wrap your head around 100,000,000 years (100 million years).

The PNAS article is describing the biosynthetic pathway of some interesting and unique lipids made by the green alga Botryococcus braunii. B. braunii has always been described as a good target for biofuel production because it produces more lipids than any other microalgae described and it produces the unique botryococcenes that would be an easy-to-use lipid source for making biofuel. The only problem with B. braunii (and this is well documented) is that it grows super slow and thus makes it a challenging strain to grow for industrial use. The description of the genes involved in the synthesis of botryococcenes takes us one step closer to being able to engineer this pathway into an organism that grows faster. In my opinion this is a good idea in the world of algae biofuel ideas. The PNAS article briefly cites some articles that have found evidence of Botryococcus braunii lipids in the geologic record, one dating back to around 500 million years ago. It was a requisite reference to what is known about this organism, and well placed in the introduction.

The article in ScienceDaily took this idea and thought it was cool enough to make a catchy headline out of. Yes B. braunii is old, but so is the whole green algae lineage. There is not any evidence that Botryococcus is any older than any of the other greens often considered as biofuel strains (such as the many "Chlorella" species). The phylogenetic tree shown above,and published here, demonstrates that. There are lots and lots of green algal trees published, this is just one that I have published that has all the Botryococcus strains/species on it. Each step along the tree can be considered in evolutionary time, and nodes closer to the leaves of the tree are more recent than nodes deeper in the tree. So, it is not incorrect to say that Botryococcus is ancient but it is incorrect to believe it is any more ancient than other similar groups of green algae. Just for context, the most ancient groups of green algae could date back 1.6 billion years according to some interpretations of fossils from that time. It is also true that geologic evidence suggest that it has contributed to preserved organic carbon on a number of occasions but it is a fresh water organisms and to that that most of the oil that runs the planet, which is marine sourced, came from Botryococcus would be an exaggeration.


  1. Robin-
    Hello! This is Dave Bapst, we met at FHL about three years ago.

    This reminds me of when you talked about your research with my invert-zoo class at FHL and someone asked what algae accounted for most of the oil we use. You said that was an good question.

    Tangentially, do you believe there is any good evidence for which phytoplankton groups dominated in the marine realm prior to the Mesozoic? This has long been interest to me as a graptolite worker, but it doesn't seem like there is any substantial evidence one way or another.
    -Dave Bapst, UChicago

  2. Hey Dave -- nice to hear from you.
    Re: evidence for marine phytoplankton before the Mesozoic;
    There is lots and there is a general consensus in the paleo and organic geochemical world that the evidence points to green algal phytoplankton were present and sometimes abundant in the late Precambrian and Paleozoic (+ lots of seaweeds). This evidence for the phytoplanton includes organic walled microfossils, sterane biomarkers, and a biopolymer called alagaenan. For the fossils, many of which are small organic wall microfossils that are spheres (some ornamented and some not). Among these fossils are examples that I personally feel confident are green algae and others that are more ambiguous. The same is true of the lipid biomarker record of steranes and algaenan. I spent most of my thesis work trying to answer this question using looking at modern things to understand the fossils, steranes, and algaenan. I have too much to say about it for a little comment. If you are curious about detailed commentary on the evidence, and what my experiments on living things tell us, I can send you my thesis and I will try to get motived to sum in all up in a blog post.


  3. Am I getting this right? The scientists isolated the pathway that produces the oil in B. braunii and then engineered yeast to produce the same oil.

    Instead of explaining why this may be awesome, the Science Daily writers decided to focus on the evolutionary "age" of B. braunii and claimed that most of our hydrocarbons comes from that organism (which is wrong and the paper doesn't claim).

    Weird. Why? I don't see this as a better story than the real thing would have been...