Tag Archives: evolution

Open seminars: a new and good idea

One of the things I liked best about being an academic researcher was group meeting. Every week, a different student or scholar would present some fresh data from their own projects. And these meetings were casual and interactive: you could interrupt any time with questions.

In industry chances to keep up with fundamental discovery science outside of your own core area can be more limited. Folks (mainly job candidates) do visit the corporate world to give research talks, and of course industrial scientists still attend conferences, but those interactions — while invaluable — aren’t as informal. The work presented is always well-polished, and people usually shy away from long technical questions and discussion.

That isn’t the case with MicroSeminar: it’s a new(ish) online-only, publicly accessible research seminar in microbiology created by Jennifer Biddle and Cameron Trash. Once a month or so, people from all over the world log into a Google Plus hangout, or watch YouTube — live or when you get free time — as some of the new fresh hot research in environmental microbiology, microbial ecology, and biogeochemistry gets presented. The feel is informal, with lots of Q&A, and you don’t even have to leave home (or bed!). Here are some of the talks I’ve enjoyed so far.

And don’t just take my word for it. Here are some similar thoughts from Pat Schloss:

The cost of going to ISME [a conference] in Korea this summer? In the thousands. Cost of sitting with your laptop watching a seminar? Zilch. Jennifer is correct that this won’t kill conferences. Conferences have a huge social aspect and provide great opportunities for networking. But the science is frequently stale and pulled from the pages of last year’s AEM [a journal]. I think there’s great potential with this model to change how we disseminate information to our colleagues. Like I said, I think this is big, deserving of your attention and perhaps others will create parallel online seminar series that are either more specialized or more general.

And if microbiology isn’t your cup of tea? If you’re an academic in a different field? Like Pat says, maybe you should start another online seminar program like this one.

DNA that copies itself

Nucleic acid templates like DNA and RNA usually need to be copied by proteins. They can’t reproduce on their own. But if you believe in an “replication-first” version of the origin of life, you’ve got to suppose that at some point a polymer developed the capability for template-directed reproduction of itself. So can self-reproducing nucleic acid polymers exist? Now we can say, yes they can — it is the latest report from Jack Szostak’s lab at Harvard. Pretty amazing stuff. (And I guess I should say it isn’t actually DNA that is copying itself, but rather 2′-NH2-ImpddNs.)

A new function for GFP

As far as I know, biology has no anthropic principle, but if it did, it might say that green fluorescent proteins (GFPs) evolved so that biologists could clone it out of jellyfish and into just about any other type of cell for use as a near-ideal reporter gene.

But the more relevant principle is the Cnidarian principle, which says that since GFP evolved in jellyfish, jellyfish must be using it for something. And no one really knows what that something is.

The mystery got more complicated a few weeks ago, when a group of chemists at the Shemiakin-Ovchinnikov Institute of Bioorganic Chemistry showed that GFPs are not just “passive light absorbers/emitters”, but can also be photo-activated reducing agents for biological molecules like NAD+, flavins, and cytochrome c.

First, it’s amazing that no one noticed this property of GFP before. Its safe to say that tens of thousands of researchers, including me, have used and studied some kind of GFP variants in the last few decades. And we all missed seeing this fundamental property of GFP.

Second, it raises the question of how important this newly discovered aspect of GFP might be to the natural biology of jellyfish and other organisms. I hope to have more to say on this second topic in the near future.

Brain Rules vs. 10,000 Year Explosion

These two books fell into my hands at the same time. Reading them concurrently was quite interesting.  They paint starkly contrasting pictures of the human brain.

Brain Rules (pgs. 4-5) says the brain’s formative period, evolutionarily speaking, was on the Serengeti:

The brain appears to be designed to solve problems related to surviving in an unstable outdoor environment, and to do so in nearly constant motion.

10kYE (pgs. 74-75), in contrast, says:

Many [alleles] are very recent: the rate of origination appears at about 5,000 years ago in the European and Chinese samples, and at about 8,500 years ago in the African sample. […]  Many involve changes in metabolism and digestion, in defenses against infectious disease, in reproduction, in DNA repair, or in the central nervous system [emphasis mine – CF].

10kYE (pg. 98) later elaborates on this idea:

The most interesting kind of genetic changes are those that affect human personality and cognition, and the evidence is good that such changes have indeed occurred. […] Several of the new alleles have effects on serotonin, a neurotransmitter involved in the regulation of mood and emotion. […] And there are new versions of genes that play a role in brain development: genes that affect axon growth, synapse formation, formation of the layers of the cerebral cortex, and overall brain growth.

Brain Rules (pg. 81) says “Universally experienced stimuli…follow strict Darwinian lines of threats and energy resources.”

10kYE (pg. 112) says:

The polymorphism [the7R allele of the DRD4 {Dopamine Receptor D4} gene, associated with Attention-Deficit/Hyperactivity Disorder] is found at varying but significant levels in many parts of the world, but is almost totally absent from East Asia….It is possible that individuals bearing these alleles were selected against because of cultural patterns in China.

Brain Rules (pg. 10) describes our evolutionary history this way:

When our bountiful rain forests began to shrink, collapsing the local food supply, we were forced to wander around an increasingly dry landscape looking for more trees we could scamper up to dine.  As the climate got more arid, these wet botanical vending machines disappeared altogether.  Instead of moving up and down complex arboreal environments in three dimensions, which required a lot of dexterity, we began walking back and forth across arid savannahs in two dimensions, which required a lot of stamina.

10kYE devotes an entire chapter, titled “Medieval evolution: How the Ashkenazi Jews Got Their Smarts”, to informed speculation that Ashkenazi Jewish brains have profoundly evolved in the last 1000 years.

Our brains’ evolution either stopped when we were hunter-gatherers and has had no time to adapt to the hugely different set of risks and stimuli provided by modern society, or it didn’t.  Cochran and Harpending admit some of their specific examples are speculative and unproven, but in general, they are solidly convinced that humans and human nervous systems have been evolving rapidly in the last 10,000 years. In contrast, Brain Rules is rooted to the idea that the cubicles of our modern workplace or the desks of our modern class rooms are “anti-brain”, because our brain evolved in hunter-gatherers who lived in open grasslands. The tension between these two core ideas seems inescapable.

I am no neuroscientist; I am just an outsider looking in. But my sense is that Harpending and Cochran are challenging neuroscience orthodoxy, and that Medina’s book is, scientifically, a distillation of current mainstream thought. It will be interesting to see how well the ideas of Cochran and Harpending catch on in coming years.