The Kaspari Lab

The Ten Principles of Ecology

I have been teaching a course called “Principles of Ecology” at OU since 1996. It was a traditional two one-hour lecture, one three-hour lab for most of those years. In 2013, I decided to flip the course, converting the lectures to workshops, and asking students to do more reading outside of class. The goal is to allow for more hands on “learning by doing” activities in the workshops, and to more tightly linked lab and fieldwork to workshop data analysis and interpretation. All in all it has been an exciting, often unnerving, but very satisfying transformation. One that is ongoing.

All along it occurred to me that the title of our course strongly implies that there is a finite number of useful principles that our students should internalize. Moreover, if the list and the principles themselves are sufficiently pithy, we should be able to cover them at the beginning of the course, rather than unveil them, one after the other, as the course proceeds. The advantage there would be that students get the big picture early, allowing us to revisit and recombine different suites of principles to build and explore new concepts and ideas. That’s the idea, at least.

I had two inspirations for this venture. One was Eugene Odum’s classic “Fundamentals of Ecology”, the famous “yellow book” that was the go-to text for much of ecology’s early years. Odum organized the book around chapters with titles that begin “Principles and concepts pertaining to….” (e.g., “Limiting factors).  He would then carve each chapter into a series of expositions each with a “Statement”, followed by an “Explanation” followed by “Examples”. I just love Odum’s book and this organization because it fits so well how I organize my own thoughts. I recommend finding a used copy. It holds up remarkably well.

The second inspiration was Meghan Duffy’s and colleagues’ recent discussion of how to organize an Intro Bio version of Ecology. I think I lifted Principle 2 and 4 directly from that blogpost. Lots of good pedagogy there.

So here is my working list of the Ten Principles of Ecology, stated first as tweet-worthy statement, followed by a short explanation of each. The idea is that my 48 students will be seeing this the first week of class and we will sample, expand on, and recombine them throughout the rest of the semester.  I realize every ecologist is different, and that this lays bare my own intellectual DNA on the subject. None-the-less, I’d love to see more lists like this.

Also, has anyone else tried a similar approach to structuring their class?  That is, start with the big picture, then backfill? I’d love to hear about it.


The Ten Principles of Ecology

1. Evolution organizes ecological systems into hierarchies.

Individual organisms combine into populations, populations combine into species, species combine into higher taxa like genera and phyla. Each can be characterized by its abundance and diversity (number of kinds) in a given ecosystem or study plot. How and why abundance and diversity vary in time and space is the basic question of ecology.

2. The sun is the ultimate source of energy for most ecosystems.

Life runs on the carbon-rich sugars produced by photosynthesis; every ecosystem’s sugar output depends on how much solar energy and precipitation it receives.

3. Organisms are chemical machines that run on energy.

The laws of chemistry and physics limit the ways each organism makes a living and provide a basic framework for ecology. The supply of chemical elements and the sugars needed to fuel their assembly into organisms limit the abundance and diversity of life.

4. Chemical nutrients cycle repeatedly while energy flows through an ecosystem.

The atoms of elements like C, N, P, and Na go back and forth from spending time in living to spending time in dead parts of an ecosystem. But the photons of solar energy can be used only once before they are lost to the universe.

5. dN/dt=B-X+I

The rate that a population’s abundance in a given area increases or decreases reflects the balance of its births, deaths, and net migration into the area. Individuals with features that improve their ability to survive (i.e., not die) and make copies of themselves will tend to increase in that population.

6. dS/dt=D-X+I

The rate that the diversity of species in an area changes reflects the balance of the number of new forms that arise, those that go extinct, and those that migrate into the area. Individuals and species that have features allowing them to survive and reproduce in a local environment will tend to persist there.

7. Organisms interact—do things to each other—in ways that influence their abundance.

Individual organisms can eat one another, compete for shared resources, and help each other survive. Each pair of species in an ecosystem can be characterized by the kind and strength of these interactions, measured as their contribution to dN/dt.

8. Ecosystems are organized into webs of interactions.

The abundance of a population is influenced by the chains of interactions that connect it to the other species in its ecosystem. This often leads to complex behavior, and a key challenge in ecology is to determine what patterns of abundance and diversity can be predicted.

9. Human populations have an outsized role in competing with, preying upon, and helping other organisms.

Humans are one of millions of species embedded in Earth’s ecosystems. The ability of humans to change the planet, abetted by our large population size and technological prowess, increases our ability to shape the biosphere’s future. Humans, through principles 1-8, are currently changing the climate, re-arranging its chemistry, decreasing populations of food, moving around its species, and decreasing its diversity.

10. Ecosystems provide essential services to human populations.

These include products like timber, fiber and food, regulating water and air quality, and cultural benefits like recreation. A key goal of ecology is to use principles 1-9 to preserve ecosystem services.


 

A slightly less paradoxical paradox

All organisms are built from the same recipe of 25 or so elements, and so it makes sense that as you increase the supply of those building blocks to an ecosystem, you should be able to increase the number and variety of organisms that ecosystem supports. Deserts vs. rainforests, right? In a paper just out from a terrific collaboration,  we show, it turns out, things are not quite that simple.

The background

Michael Rosenzweig

Michael Rosenzweig

In 1971, Michael Rosenzweig (MikeK’s Ph. D. advisor and friend of the Kaspari lab) used a suite of differential equation models to explore why adding nutrients to an ecosystem so often reduced, not enhanced, the number of species. He coined the term “Paradox of Enrichment” to capture this incongruity. Since then Rosenzweig and a who’s who of ecologists–particularly terrestrial botanists–have documented this Paradox and compiled a long list of mechanisms that could explain it.

A few years ago, our lab joined a team of collaborators to take on the relationship between nutrient availability and diversity in tropical soils. We did so using a grand experiment initiated by Joe Wright and colleagues at the Smithsonian Tropical Research Institute in Panama.  Since 1998, we have been fertilizing 40×40 m plots with the “big 3” nutrients–Nitrogen, Phosphorus, and Potassium–as well as a cocktail of micronutrients from Boron to Zinc. In 2012, as part of an NSF MacroSystems grant, we visited each of these plots, sampled soil and litter, and used a variety of molecular and traditional methods to count the number of species of bacteria, fungi, and invertebrates on the essentially 9 different kinds of tropical soils generated by this experiment.  I would say that our results, out early online in the journal Ecology, were surprising, but, what happens when you quantify the absence of a paradox?

Gigante Fertilization Experiment

The Gigante Fertilization Experiment, one of the largest, and longest running such planned experiments on Earth. (You can say that humans are actually doing a pretty good job of adding Nitrogen and Phosphorus and a variety of metals to Earth’s ecosystems in a less scientific, tho none-the-less deliberate manner).

The results are wonderfully complex, but here are some highlights.

Bacteria, Fungi, and Invertebrates each had their own “biogeochemical niche”.

If you plot out the magnitude of diversity responses to nutrients–positive or negative–the resulting fingerprint differed among the big three soil supertaxa. Everybody’s diversity suffered when nitrogen alone was added. This is as close as you get to a uniform Paradox of Enrichment. After that, Bacteria increased the most (and modestly) with phosphorus (P), fungi were all over the map but tend to do better with potassium (K), and invertebrates showed the biggest increases when combinations of nutrients were applied.

Why does nitrogen do a number on soil diversity?  The standard explanation is that there are a handful of weedy taxa that just thrive when nitrogen is superabundant (fertilize a prairie with urea and you wind up with tall, green patch of invasive grass). But we find little evidence for that: things that increase on N plots tend to be rare, and increase when any nutrient is added (and some of them are icky. See below).

Instead, we suggest that nitrogen, which tends to acidify the soil, sets off a chain reaction by which aluminum–a toxin to most life–leaches into the water supply and bathes the unfortunate members of the brown food web in a bath of metal. In other words, nitrogen doesn’t seem to favor a suite of nitrogen specialists, it releases an all-purpose toxin that stresses everybody out.  That’s our new working hypothesis. It needs to be tested.

Fig 1 Richness ES w treatment.JPG

A summary of our results. The Effect Size is a way of uniformly expressing the change in diversity, positive or negative ,of a fertilizer compared to unfertilized plots. For example,  fertilizers tend to have a bigger effect on invertebrates than bacteria. More and more complex fertilizer combos are arrayed toward the right. 

Combo’s of nutrients often enhance diversity more than individual nutrients.

One common pattern among plants is that if adding one nutrient, say nitrogen, drops diversity in a prairie, adding two, say nitrogen and phosphorus, does so even more. We don’t find much evidence for that. Instead, the two groups with big, complicated genomes–the fungi and invertebrates–show the largest increase in species diversity when micronutrients are added. Invertebrates do almost as well when the big three nutrients, N, P, and K, are added in tandem. What is it about nutrient combos that favor mushrooms and ants?

We suggest that one reason is that critters with large genomes need a ready supply of chemical elements to build and maintain their more complex metabolisms. It is fun to ponder such a link between an organism’s metabolic diversity–the number of enzymes it has linked together in intricate pathways (many of which require a metal like Zinc or Copper to operate properly) and its metal-craving. Again, this is a working hypothesis. But we have already shown that decomposition in this system–the combined action of the metabolisms of the brown food web–shows big increases on the +Micronutrient plots in the Gigante experiment.

Of the three soil supertaxa, the bacteria and invertebrates have the most similar biogeochemical niches.

One might have guessed that fungi and bacteria–both “microbes” that break down “detritus”*–might respond similarly to the same nutrients, but this doesn’t seem to be the case. Fertilizers with a strong effect on bacterial diversity tended to have little effect on fungi, and visa versa. On the other hand, the fertilizers that really knocked down bacterial diversity, N and NK, did the same for invertebrates.

Many soil inverts have rich microbiomes in their guts that allow them to make a living in the brown food web. Could this be one cause of their similar responses. Does the gut flora of millipedes also suffer in bacteria-poor soil?

Fig 2 Covariance of Diversity Responses

When you contrast the effect of a fertilizer on diversity between each combo of the soil supertaxa, fungi and prokaryotes (bacteria) do their own thing, while bacteria and invertebrates tend to response more similarly. 

There are weedy taxa in each of the three supertaxa

Which taxa thrive regardless of what nutrient you drop on the soil? It is somehow satisfying to find that among the invertebrates, the Blattaria (aka roaches) can’t say no to any fertilizer.

It is a little more chilling that among the fungi, only the Chytrids, a phylum that contains the infamous B. dendrobaditis, a deadly pathogen of amphibians, increases in diversity in response to almost any fertilizer.  We are fertilizing the planet. Just a pattern thus far. Someone should look into it.

Fig S1 Effect sizes by subclades

Subtaxa of the soil supertaxa that respond positively or negatively to a given fertilizer by at least one standard deviation over controls. See paper to suss out all the abrev’s.

What’s the take home?

Humans are rearranging Earth’s biogeochemistry–depleting fertile soils through erosion and dumping enormous quantities of N, P, and C and a mess of metals into the biosphere. Our study contrasted three grand hypotheses for how fertilization shapes diversity–by increasing abundance, by favoring a subset of competitive species, or by acting as toxins. Much of what we ecologists know about these nutrient effects comes from the experiments of our botanical colleagues. And those experiments consistently point to fertilizers favoring a subset of high-nutrient specialists that drive other species locally extinct. The Paradox of Enrichment is thus an inevitable result of simplifying the environment with fertilizers to favor a handful of species.

But by focusing on three soil supertaxa–the bacteria**, fungi, and invertebrates–that account for most of the diversity of life on dry land, we find evidence for some nutrients enhancing abundance, others acting as toxins and for combos of nutrients ameliorating toxic effects. For some of the reasons why, check out our Discussion. Not surprisingly, spatial scale comes into play. And how metabolisms are rejiggered.

An enduring question is how the combined diversity of life in any given ecosystem–from trees to mites to microbes–will respond to the slings and arrows of anthropocene fortune. The answer “it’s complex” shouldn’t surprise. At the same time, one path ahead, we think, lies in  contrasting how tiny organisms with effectively infinite population sizes and evolutionary potential to match respond to global change compared to their large colleagues that can be comfortably enumerated with m2 quadrats.


*Combining fungi with bacteria** as “microbial” is akin to combining petri dishes and planets as “matter-intensive phenomena”.  Likewise “detritus” can be anything from a dead leaf to a dead armadillo. *Celebrate* the diversity.

**Again, I beg forgiveness from microbial ecologists for using the shorthand “bacteria” or “prokaryotes” to lump together the archaea and eubacteria. I was raised by ornithologists.

A short essay on Koechner’s Criterion and its relationship to success in Grad School

During a layover at DFW airport, I opened Twitter to find a lively discussion spurred on by Terry McGlynn, @hormiga, who (and I paraphrase) encouraged grad students to seek mentors who encouraged living normal lives, using the specific example that Saturday work days should not be mandatory.

The thread quickly expanded into one about work/life balance in academia, many of the arguments and counterarguments (in the form of tweets and counter-tweets) appeared to hang on definitions both of success and what “normal” looks like or should look like in a better world. All of it had the subtext that bubbles under many such discussions—“Am I working hard enough?”. In my experience, there are few more troubling questions to an academic scientist, or any creative person.

I dedicated a blog to this and related subjects in the (my gawd) late 2000’s called “Getting Things Done in Academia” (rebranded “Survive and Thrive in Grad School”) that is moribund but still out there, and hopefully moderately useful.

So there I was, sitting in the airport, waiting for my flight to OKC, and reading tweets and counter-tweets on an important subject that I obsess about. What was I to do?  I tweeted the longest thread of my TwitterCareer, I think. Three whole tweets. I started with the proviso that Twitter is a mixed bag for holding such discussions (Boy Howdy, nothing like leading with understatement). Then, because I found it an intense distillation of one view, I quoted EO Wilson’s comment from Advice to a Young Scientist, that said for a real scientist, every vacation should be a “working vacation”. I ended with my thoughts on that key question “How hard should I work as a grad student/academic?”.

I thought I’d add a few observations. In the spirit of Twitter, they will not be organized into a coherent whole ;-). I suppose I could blast out a thread, but it is easier to get some thoughts down in one place, as a blogpost, and link to them. (I wonder if such a stratagem, once things get hot, might be a productive way to carry on the discussion. As good as Twitter is for starting a discussion, I would rather read one continuous argument).

Assumptions and Definitions

1) The best definition of a successful life, that I’ve yet heard at least, is from the comedian David Koechner, @DavidKoechner, who said

“If you are doing what you love and have someone to share it with, congratulations, you are a winner.

I think this should be called Koechner’s Criterion. I mean, does it set up a discussion of work-life balance, or what?

2) Scientists are scientists because they are intensely curious about how Nature works, and want to discover new stuff and share those discoveries with others, particularly those that are curious about the same stuff. The most successful scientists, however we define them, do this discovery/sharing stuff more and better than others. They also have a higher probability of getting jobs where they are paid to do science.

3) We live in a stochastic universe where sheer dumb random luck can be important and bad luck is rampant.

4) There are skills,  mental attitudes, and societal tweeks that, once achieved, improve our chance of being successful.

5) We spend much of our lives pursuing 1, desiring 2 as part of 1, fearing 3, and seeking 4.

Observations

1) There are as many formulae to being a scientist (or artist, teacher, craftsperson) as there are people. But I think that all routes to mastery include a passion for the subject, an aptitude for it, and a desire to create the opportunities that will allow one to develop and prosper. For many people, this leads to a more or less single-minded devotion early in their careers to master a difficult task. However, the diversity of humankind guarantees that there are other folks whose sheer brilliance will allow them to succeed without breaking a sweat. There are still others who are amazingly effective, doing a lot with less time, because of, not in spite of, their strong relationships. Against that diversity of approaches all are judged by a common outcome: the discovery of new things and sharing them with an interested audience.

2) There are also a lot of ways folks decide to share their lives together (including living alone), and the best institutions honor that variety. Family leave, maternity leave, equal pay for equal work, are all hallmarks of a civilized society, in no small part because they help each person fulfill their potential.

3) The happiest biology departments I know find a way of of making steady progress toward maximizing Koechner’s Criterion for their faculty, post docs, staff, and students.

Conclusions in the form of suggestions to Grad Students

1) A key task in a young scientist’s career is to find a mentor who is the best match for the way they seek to develop their career and maximize Koechner’s Criterion. The single best way to find that match is to talk to the graduate students and post docs of possible mentors.

2) It is an old, but true adage that its not just the time you put it, but how you use that time (i.e., working hard versus working smart). If you haven’t already done so, read these two books: The Seven Habits of Highly Effective People by Stephen Covey, and Getting Things Done by David Allen. Seven Habits focuses on the strategy of designing a creative life, GTD is about tactics. There’s work-life balance baked into both of them.

3) Unplug. Daydream. Daily. One key element of Zen Meditation is to calm the Monkey Mind. Twitter and Facebook are the Monkey Mind incarnate. Your best ideas will come to you when you release yourself from the data stream. That also means your best ideas will likely come to you on vacation, so don’t forget to bring a notebook.

4) One good way to center yourself and set your own expectations is to read memoirs of scientists. Sapolsky’s A Primate’s Memoir, Fortey’s Trilobite, and, of course, Jahren’s Lab Girl are all awesome and different.

5) I would be remiss if I didn’t conclude this essay by plugging EO Wilson’s Advice to a Young Scientist. Since when does one read an advice book in which you agree with everything in it? The book presents a series of chapters that have got a lot of discussion going  (one review). Find a new or used copy, or check it out from the library. Or start with Wilson’s Ted Talk on the subject.

Herbivores like a little salt with their protein

One of the questions that drives a lot of our work is “Of the 25 elements required to build organisms, how many of them help regulate the abundance, activity, and diversity of organisms in ecosystems?”. In a freely available paper just out as a Report in Ecology, we provide a framework for the many ways that nutrients can interact, then test how Sodium (an AntLab favorite) and Nitrogen+Phosphorus (the preferred pair of the “Stoichiometric-Set”) interact to shape the abundance of the invertebrates above- and below-ground.

We were particularly keen on seeing if Na acts as a catalyst, increasing an insect’s ability to efficiently convert Nitrogen and Phosphorus into more insects, or if the two sets of nutrients acted more or less independently.

figure-1

Four possible ways that two sets of nutrients can interact. We were betting on Serial C0-limitation, where Sodium catalyzes access to N and P. Didn’t always turn out that way.

The experiment was pretty classic field ecology: we furnished m2 plots with either water, N+P in the quantities used by the NutNet experiment, 1% NaCl solution, or both. We measured the soil and plant responses, and bugvac’ed the above-ground invertebrates with a modified leafblower (see picture above). For below-ground invertebrates, we used a very messy, but unfortunately best method available, flotation extraction of soil cores from the center of each plot.

soil-core-saltgrass

A soil core from one of the experimental plots. Somewhere in there lurk oribatids, collembola, and other tiny inverts.

As an aside, as someone who cut his ecological teeth in the Nebraska Sandhills for his undergrad and master’s work at the University of Nebraska (see below), and has spent a good fraction of my days since then in the tropics, I am very much enjoying spending time in grasslands again. An NSF project with Nate Sanders on the role biogeochemistry plays in grassland food webs will keep me in the grass for the next few years.

kaspari-sandhills-1982

A 21-year version of Mike Kaspari above WhiteTail Creek in the Sandhills of Nebraska. Note the Nikon K-100 camera, and the spiffy digital watch. And yes, those are cutoff jeans. It was a different time then.

After the sampling came the microscope work. Leafhoppers are by far the most common insects in the aboveground samples, and their mobility and subsequent ability to respond quickly to manipulations is something we want to investigate further. As predators go, spiders were common and diverse, and clerids were the most common beetle group.

cicadellidae_saltgrass2015_normanok_110522_d

Looking forward to getting to know the leafhoppers, a group whose English name is simple, and whose latinate name defies easy memorization.

 

theridiidae_blackmask_saltgrassjuly2015_f_d_110556

One of the big questions going forward is how quickly predators accumulate on plots that first attracted their prey. The spiders were dauntingly diverse on this patch of Oklahoma prairie.

 

cleridae_saltgrassjuly2015_normanok_d_110409

One of the greatest pleasures of invertebrate microscope work is getting acquainted with taxa like these clerid beetles that are common, but that I’ve never had the occasion to look at before.

Results: Both sodium and N+P shape both communities, but in different ways

In the grass and forbs above-ground, all three treatment plots differed from controls. Adding salt increased the abundance of insects, and adding N+P increased it even more so. However, these effects seemed to be independent of each other (strike one for the Na as a catalyst hypothesis). Since plant height and mass increased on N+P plots and not on Na plots (suggesting that while NP was a nutrient for the plants, adding Na had no negative effect on the first trophic level), we think that NP provides a double bonus of more food, and more habitat, while Na just provides the food. We will test this idea more this coming summer.

Below-ground, however, was a different story. Here Na seemed to act like a catalyst. Alone it had no effect on the oribatids and collembola that dominated belowground. But combined with NP, it boosted the modest increase of abundance where NP was added by itself. Here, our working hypothesis is that NP fertilization increases the food supply, and thus increases the demand for Na. We are keen to follow this up this summer as well.

So there it is, so far. The plans are to expand both the kinds of experiments and their distribution, to add experiments farther north in more Na-deprived grasslands. One project has a particular appeal: as NP + NaCl is roughly the recipe for urine, and urine is the single most effective way to fertilize a patch of prairie, how do community dynamics respond to a splash of Bison Piss?  Is there a predictable succession?  And how do the hundreds of species find, exploit, and deplete this resource? What are the patterns of succession?  Lots to learn.

 

When the science news is bad, write your local paper

Note

Recent events have found me struggling to find some way to be useful. I decided that one thing I could do was to write–on a regular basis– a letter to the editor of the The Norman Transcript, our local paper. The bad news from Crowther et al in Nature served as the grist for this week’s letter. Writing it scratched a number of itches: it gave me a shot at explaining negative and positive feedback, it provided readers with actual phone numbers (not just the link in this version) to phone the local offices of our Senator’s and Representative, and it pressed the notion that there is always hope when people engage, even when times are dark. Below is a slightly modified version of the letter.


To the Editor:

Last week was a bad one for Planet Earth. While her workings are pretty complex, it has long been evident that when we pump millennia-old carbon into the atmosphere we warm the planet. Many of us scientists had hoped that this warming would be slowed by a variety of feedbacks. Trees, after all, scrub CO2 from the atmosphere; more gets sucked up by our oceans. That, we hoped, may buy us more time to move away from fossil fuels and build the solar panels and windmills that are springing up over the state. These natural feedbacks protect us in the same way that, when you notice a bridge is out, you step on the brakes long before catastrophe strikes.

Well, there is another kind of feedback, and for that we can thank the microbes. Boatloads of carbon rest in the cold earth. And, just as we keep our bacon in the fridge to keep it from rotting, that cold earth has kept its microbes from chewing through the countless tons of dead carbon just below our feet. Now, 49 scientists have together revealed in the journal Nature that the warming Earth is waking the microbes from their cold torpor. And they are hungry. As the microbes break down the soil CO2 pours into our atmosphere. This warms the Earth and makes the microbes even hungrier…

You are, by now, beginning to see how this other feedback works. It is as if, back in the car, you stomp on the brake pedal. Or…what you *thought* was the brake pedal. The car lurches forward, racing toward the chasm. So you stomp harder! (Why aren’t these brakes working??) In the same way that the car accelerates toward the chasm, every fraction of a degree that we further warm the planet drives Earth’s microbes to empty one of its last storehouses of carbon, making the problem even worse.

Bad timing, right? Just as we should be redoubling our efforts to find a solution, prez-elect Trump calls climate change “bunk” and his advisor on NASA wants to delete such “politicized science” from its budget. This is code for the hundreds of satellites that watch our Earth, informing our farmers about soil moisture, our sailors about sea ice, our friends and neighbors about approaching storms. All because some of that data is used by scientists to diagnose our warming planet. It is bad enough our car is hurtling toward a cliff. Trump’s NASA policy would disable the speed gauge and paint over the windows.

Now more than ever we need to phone our Senators and Representative. We need to urge them to preserve NASA’s world class Earth Observatory program. Why do I think you and I can convince climate change deniers that we need to do more, not less? Because over the past 23 years at OU I have had the privilege of teaching science to thousands of Oklahomans. These young citizens see the evidence, and in our conversations (and in anonymized polling) overwhelmingly agree humans are warming the Earth and that there is still time to save it. Full stop. These same people are our future governors and legislators, will be paying taxes when some of us are retirees, and are thinking about raising families of their own. I suspect these are some of the same people who will be answering the phone when you make those calls. They are our future. They are our hope.

Mike Kaspari
Norman Oklahoma

One way to build a dietary generalist

By Karl Roeder

We are incredibly excited to announce that our work on fire ants and isotopes has just been accepted in Ecology! The work primarily revolves around understanding trophic variation across a population of one of the model organisms of myrmecology: the red imported fire ant, Solenopsis invicta. Essentially, we are looking at where you rank in a food web and what did you eat to get there. To expand upon this, we had been thinking about ways to understand the how, what, why, and where of stable isotope variation that regularly occurs in the published literature. Stable isotope analyses have increased in their use in ecological studies as a tool where nitrogen (d15N) can be used to understand trophic position/structure and carbon (d13C) can be used to map out where the dietary source came from, in this case C3 or C4 plants.

Despite a lot of myrmecologists loving morphological measurements, it seems few had tested how size, both body and colony, may affect trophic variation within a species. A question that we were intrigued with. Perhaps even more surprising was a real lack of good information at the colony level, as most stable isotope studies with ants focus on differences across species in an assemblage or community. We set out to answer these question by measuring a variety of different sized workers and colonies across multiple time periods throughout a year in a small 0.5-hectare old field in Oklahoma. To our surprise, we found an unprecedented range of values occurring within a population. A range that was comparable to whole ant assemblages from prairies to tropical rainforests. The red imported fire ant, while acting as a generalist at the species level, may in fact be specializing on particular dietary items at the colony level.

While there are still mechanisms to work out, we believe this is a wonderful step towards disentangling the trophic ecology of the red imported fire ant and potentially other invasive species. Given the wide diet breadth we observed in such a small area, we hope this will encourage researches to think more about the natural history of their study species, and combine this information with physiological measurements to really attack questions surrounding their biology.

This work was generously funded both by the National Science Foundation and a University of Oklahoma Biological Station summer fellowship.

 

What journal gets the first peek at your manuscript? Results from a year of ruminating.

For the past year or so I’ve been ruminating about a problem common to academics: Once you have completed a MS, where do you send it? And how do you follow that process through to completion (i.e., publication)? The literature explosion, as well as the increase in venues and ways to publish, has made this topic an acute one.

What follows is my provisional conclusions from these ruminations: Best Practices V1.0. These practices arise, hopefully somewhat logically, from some axioms. Both have been particularly shaped by discussions with Nate Sanders, by a terrific essay by Brian McGill and by multiple tweets, blogposts, and discussions with Ethan White.

That said, I strongly suspect they will disagree with some of what follows. But then, the more I work on this problem, the more I see that its solution lies somewhere within the remarkable g’mish of practicality, laziness, efficacy, ambition, fear of mortality, and ethics that characterizes doing science nowadays. I, like you gentle reader, am just trying to figure out what works. And caveat emptor: all that follows arises from the consideration that I am a mid-career professor. I suspect much of this will ring true to most. But I hope to see how other folks–grad students, post docs, junior professors, folks at undergrad institutions–formulate their own best practices.

My Motivator

Ecologist’s die with 99% of what they have learned between their ears.” Dan Janzen.

I was a sophomore at a faculty reception for Janzen at the University of Nebraska when he made this offhand remark. It has never been that far from my thoughts since. It came to a head in the past couple of years,  when I found myself spending too much time revising papers rather than working up data. As a consequence I was falling increasingly behind. This is bad news for any number of reasons: 1) somebody paid for those studies;  2) when they paid for it they implicitly contracted me to analyze it (not just dump it into the grey literature); and, 3) I really want/need to know the answers–out of sheer curiosity and my desire to move our science a wee bit forward. Which led me to spend some time, in quiet moments, over emails, and over beers, coming up with

My Axioms

1. The biggest improvement in a MS happens from Draft 1 to Draft 2.

That improvement is maximized when Draft 1 marinates for a month or more. The process of cranking out Draft 1 wears a lot of ruts in the way I think about my question, the presentation, the results, and their interpretation. A one month hiatus allows my subconscious to work on the problem; at the odd hour, I find myself scribbling notes on various and sundry ways to fix things in the MS. That hiatus (sometimes, but not always a deliberate one in the past) has always allowed me to return with a fresh view and significant improvements.

2. Outside reviewers improve manuscripts in a qualitatively different way than the hiatus between Draft 1 and 2.

Peer reviews are gold. Peer reviewers have the useful feature of existing outside my head. They recognize flaws to which I am blind, point out weak logic that I try to force through by dint of will, and highlight when I communicate poorly (default mode: if a peer reviewer misunderstood something, I didn’t communicate it well). The availability of good peer reviews–like sufficient time, good collaborators, field station happy hours, and grant money—improves the quality of our work. Access to peer reviews should be celebrated but conserved.

Yes, of course some of them are jerks.

3. The rate of manuscript improvement is a positive decelerating function of the number of reviews.

As you work to incorporate the advice of reviewers, a fairly predictable thing happens. Subsequent rounds of reviews become less useful (even if the average length of those reviews is remarkably conserved). In short, there is a rapid saturation in quality of your manuscript with repeated exposure to peer review. In the worst-case scenario, tangible improvement gives way to the stochastic chasing of reviewer whim.

Corollary:

Time spent revising a manuscript means time taken away from other creative endeavors.

4. Papers are not read if people don’t know about them.

Corollary:

If a potential reader does see your intriguing title and abstract on a journal website, they should not have roadblocks placed between them and the rest of the paper.

5. Scientific societies are natural places for scientists to aggregate, discuss, train, synthesize, and publicize the work they celebrate.

The flagship journal of your scientific society is a go-to place for those interested in your kind of work.

Corollary:

Money invested in your society, including publication fees, is likely to go to the people and activities you believe in.

OK, we have our axioms. What do we conclude?  Here is my provisional rules of the publishing road for the next few years.

Kaspari’s Best Practices for Submitting Papers V1.0

1. After completing a MS, let it sit for at least one month.

Then open it with fresh eyes and revise as needed. Then send it for friendly review. Then, and only then, send it out to a journal, and exploit the peer review system.

2. Send the manuscript to a society journal that best matches its audience

Here is my current list:

PNAS for the very best stuff of widest interest (Bert Hoelldobler told me “PNAS is where you go when you’ve got a great story and want the space to tell it properly.”.

Next is Ecology and American Naturalist.

Next is Ecography, Functional Ecology, BiotropicaEcological Entomology, and Soil Biology and Biochemistry.

3. If a paper is rejected, do not “shop it around”.

Get it out. Ecosphere and Ecology and Evolution are two open access online journals from societies I believe in.

4. Maximize access

Not all society journals are open access. We are not where we want to be, but the times they are a changing. Be an agent of change. That said…

5. Publicize your work

Get the word out. Email PDFs to colleagues who should be interested. Given the publication glut–and my general sense of the universe’s spiraling, magnifying disarray–I am delighted when someone thinks of me enough to send a PDF they think I should know about. And it happens remarkably rarely.

Moreover, if you’ve spent all that time discovering something new and interesting, then

Tweet it

Blog about it

Post links to the paper on your website (when you can inkway, inkway)

Send your University Public Relations your pithy public summaries from social media.

Every tweet and blogpost is vital practice at communicating our science to a broad audience.

Benchmarks

How will I know in five years if Best Practices V1.0 has been a success?

  • No manuscript will remain a manuscript more than 1 year (a paper is no longer a manuscript once it is accepted/in print).
  • I will spend no more than 30% of my creative energy revising manuscripts.

Until then.

 

 

 

How to schedule a committee meeting

All graduate students face a periodic, essential chore: scheduling a committee meeting for from 30 minutes to 3 hours. For some, this may only happen three times. For others, it may happen once a year. Trying to arrange for five faculty members to be in one place can be an amazingly onerous. The longer the scheduling process drags on, the more onerous it becomes for you, for them, for everybody. So here are some tips.

Get with your advisor at the beginning of the school year/semester and, while reviewing your goals, specifically address the need for a meeting. If you agree that a meeting is called for, do the following.

  1. Agree on the agenda. Is this an “official meeting”, required by your graduate college that involves paperwork? Assemble the paperwork, and review the protocols.
  2. Write a draft of the email to your committee. Be concise, but include the need for a meeting, and the agenda, and the duration. Helpful hint: it is easier to schedule a 30-minute meeting than a one-hour meeting. It is infinitely easier to schedule a 1-hour meeting than a 3-hour meeting. Err on the side of brevity. This may mean sticking with your agenda, but, then, that’s why you have an agenda.
  3. Now, review your advisor’s schedule. Identify dates that your advisor will be around and available.

OK, so far, you’ve met early in the year/semester with your advisor to discuss plans, including the need for a meeting. You have the agenda, and have decided on the minimal amount of time to get everything done. You have a draft of the email. Now aim for 4-week period in the middle of the semester to meet. Be aware of potential trouble spots (a spate of faculty interviews) and of regular departmental time sinks (faculty meetings) that will suck up scheduling opportunities.

Drawing by Debby Kaspari DrawingTheMotmot
  1. Use your advisor’s availability as a template for an online scheduling site (I highly recommend, because Ethan White highly recommends, whenisgood). Don’t simply ask each member of your committee “When are you available in October?” (Imagine having to answer that question in detail yourself. It ain’t easy.). Remember, you want this to be as painless as possible.
  2. Now email your committee (CC your advisor), propose the meeting, time, agenda, and ask them to visit the online scheduling site and indicate their availability. Tell them that your dear advisor has already filled it out, and that it does not include shared commitments like faculty meetings, seminars, etc. Tell them it should take only 5 minutes, and that you are emailing them well ahead of time to make it as easy as possible (because you are).
  3. Stick with it until everything is done and your meeting exists on 6 different calendars, a small block of time that you worked hard for, and that is all yours. Now shine, you crazy diamond, shine.

By extension, here are a few sentences to avoid when you are scheduling.

            “I need a committee meeting, howabout late Thursday next week?” (i.e., forget to mention why are we meeting, how long are we meeting, and scheduling early enough that the committee’s schedule hasn’t filled up).

            “I know I tried to schedule our meeting a month ago, but I couldn’t get find a suitable time. I’m trying again now, and I really need to meet this semester if I want to graduate.” (i.e., don’t procrastinate, once you start the scheduling process, finish it. Until you’ve nailed down a date and time, that slot is fair game to all the other things that tend to fill up a professor’s schedule).

 “Sorry folks, but my advisor, Professor Tardy, was the last to log in to whenisgood, and he can’t make any of your times.” (Hoo boy, faux pas city. Get yer advisor on board first, particularly if that advisor is “very busy”).

In short, be early; be concise; be considerate; be professional. Bonus: you will earn the reputation for being just that.

New PostDoc to study Geographical Ecology of prairie food webs

A new NSF DEB grant to Mike Kaspari and Nate Sanders supports a 3-year postdoc who will join us to explore the Geographical Ecology of invertebrate plant consumers across North American grasslands, meadows, and roadways. Our focus is on the role sodium and other micronutrients play as unique catalysts of the vigor, abundance, activity, and diversity of above- and below-ground communities. We will combine geographical snapshots from across North America with field and lab experiments to identify and explore mechanisms. It will be grand.

We are looking for an ecologist with expertise in invertebrate ecology and an interest in testing big picture models that combine Ecological Stoichiometry, Metabolic Ecology, and Trophic Ecology. Proposed starting date as soon as January 2017. To apply, email Mike Kaspari (mkaspari@ou.edu) your CV and a letter of introduction that includes a summary of your most relevant research experience, your future research plans, and contact info for at least two references. Check out our lab’s webpage at michaelkaspari.org.

OU Biology is dedicated to growing our already considerable expertise in Geographical Ecology, including a recently completed cluster hire of three ecologists with expertise in physiological ecology, macroecology, and aquatic ecology. Join us!


NSF Project Summary

Overview

Plant populations transform CO2, water, and nutrients into tissue; detritivore and herbivore populations consume and ultimately mineralize that tissue. Geographical ecology predicts how the abundance of these populations (and their summed activity as net primary productivity, decomposition, and herbivory) covary across Earth’s ecosystems. This proposal offers a timely focus on the role of sodium as a catalyst driving the abundance and activity of plant consumers. It builds on recent work highlighting three features placing sodium at the hub of terrestrial ecology: 1) the many ways that Na availability is non-randomly distributed among Earth’s terrestrial ecosystems, 2) the failure of Na shortage to decrease plant fitness, and 3) the necessity for plant consumers to find and retain sufficient Na supplies. Combined, these elements form a framework that posits Na shortfall as a key constraint on herbivores, pollinators, detritivores, and their summed effects on communities and ecosystems. Moreover, other drivers of geographical ecology are either catalyzed by Na—adding it allows consumers to better use available N and P—or exacerbate Na shortfall–as temperatures increase, so do Na loss rates.

Field and lab experiments will be combined with comparative community studies to test how the effects of Na shortage are enhanced at higher temperatures, in ecosystems inland from oceanic aerosols, and in the absence of road salt application. In the first year, geographical variation in the abundance, behavior, and stoichiometry of focal populations will be quantified among 40 grasslands/old fields paired with associated roadsides of mesic North America. In the following two years, 7×7 m plots will be fertilized with Na in quantities mimicking oceanic aerosols, into which N and P fertilization plots are embedded. The goal will be to explore how Na shortage acts as a catalyst for plant consumers, one that decreases their activity, consumption, and N and P use efficiency relative to the plants they eat and the predators that consume them.

Intellectual Merit

Four drivers—temperature, precipitation, N, and P—have been key in predicting the geography of plant productivity. Ecology lacks an equivalent understanding of the abundance and activity of plant consumers. This proposal offers two remedies toward transforming geographical ecology. The first is a framework by which a third, powerful driver of herbivores and detritivore acts independently of plant productivity. The second is a test of this Na framework via a systematic exploration of invertebrate grassland consumers across mesic North America. If successful, this project has the potential to jump-start the biogeography of trophic structure and carbon cycling by focusing on Earth’s ubiquitous Na gradients.

Broader Impacts of the Proposed Work

We envision three. We link climate and biogeochemistry to build novel predictive models useful to community and ecosystem ecologists. In doing so, we help jump-start NEON, and build the nascent field of Roadside Ecology. We foster graduate STEM education. Given the extraordinary pace of change in how we “Do Ecology”, we will address the need for an evolving source of information on best practices with a curated living online document. We foster undergraduate STEM education. Sodium Catalyst theory is a rich source of ideas that are easily tested. We will mentor undergrads on our projects to develop and test some of these low-hanging fruit. Kaspari will develop and publish a series of three labs from his Principles of Ecology course that focus on the geography, trophic, and pollination ecology of sodium.

Brittany Benson leads AntLab BugOut!

Brittany Benson Bugout 4

Brittany Benson uses a variety of media, from her own art and insect collections, to plush stuffed mites, to convey the beauty and excitement of insects. 

Certainly one of the greatest things about devoting our lives to the study of insects is the ability to take our work on the road and share what we have learned. The AntLab’s master communicator in this regard, is taxonomist, artist, and mite expert Brittany Benson. Brittany regularly goes on the road with her Acari Safari (Acari is the scientific name for the mites she studies).Her roadshow combines costumes, her own art, an extensive private insect collection, and lots of live critters. Brittany’s charisma and charm help her convey her passion for bugs through a rolling show and tell,  a lecture and question and answer period.

Rebecca Prather BugOut

Rebecca Prather, dressed as a burying beetle, answers a pressing bug-related question. 

Brittany, helped this year by Rebecca Prather, AntLab first year grad student, visited the Myriad Botanical Garden’s annual “BugOut!”, an event in which children are invited to help release ladybird beetles in the garden for natural pest control. Brittany’s roadshow reached 1,500 on a single day this July. She is a terrific ambassador for our lab, the University of Oklahoma, and the natural world of which she is so knowledgable.