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Observing the observer

It is starting to feel like fall, although there are not many colors in the trees yet.

The colors were vivid on the day pictured in the painting below, and I fondly remember a really great hike through a hemlock-dominated ravine as part of this camping trip a few years ago. The painting was an attempt to capture a moment that I spent watching my daughter as she sketched in her notebook.


Observing the Observer. Oil on Canvas. Finished May 2017.

Field work…it’s not just the science

For me anyway.

One of the highlights of being an ecologist is spending time in the field making observations, thinking about patterns, asking questions, and collecting data to answer those questions.  In fact, it is hard to believe that we call this stuff “field work,” because as anyone that spends time in the natural world knows, simply getting out there can be a tremendous source of inspiration and rejuvenation. One of the ways that I reconnect to the splendor of “field work” is to paint. Now that the fall semester is over, I’m looking forward to spending a little time painting with my daughter. In the spirit of the holiday, below I share a few field-site and field-related paintings that have special meaning to me….

Fallison Bog Pond. Oil on canvas.  Located in northern Wisconsin, this small pond is surrounded by an extensive Sphagnum-dominated peat mat and has served as an important site in ongoing studies of peatland development (e.g., Ireland et al. 2013)

October at Fallison Bog. Oil on canvas, 2013. Located in northern Wisconsin, this small pond is surrounded by an extensive Sphagnum-dominated peat mat and has served as an important site in ongoing studies of peatland development. Started with the help of my daughter, and some of her brush strokes are still there.

October at Fallison Bog.  Fallison Bog Pond is a small peatland pond in northern Wisconsin, near the Trout Lake Limnological Research Station. The place is particularly significant for me – for both personal and professional reasons. We have been monitoring testate amoeba communities and hydrology of the bog, and other bogs in the region, every few years since 2003 (see here for more on testate amoebae). Also, we are currently investigating processes controlling peatland development, and Fallison Bog is a critical site in this effort.

The bog was also one of the first field sites that I dragged my future wife into, in a memorable trip in April of 2004. She learned the hard way that sometimes bog mats are pretty thin along the lake edge. Wisconsin water is very cold in April.

Erythrina herbacea. Oil on canvas. Growing on the sound-side of St. Catherine's Island, a barrier island on the coast of Georgia where I did my masters research.

Erythrina herbacea. Oil on canvas, 1998. Growing on the sound-side of St. Catherine’s Island, a barrier island on the coast of Georgia. An interesting plant, it apparently contains toxic alkaloids that induce paralysis (wikipedia).

Erythrina herbacea.  St. Catherine’s Island is a barrier island along the coast of Georgia in the southeastern United States. I was fortunate to spend time on the island in  1996-1998 as part of my masters thesis research on the vegetation history of the area. At the time, I was really immersed in field botany; in fact, most of the time that I wasn’t spending on my thesis research was spent collecting and identifying plants.  This specimen of Erythrina herbacea caught my attention, something about the subtle beauty of the red flowers rising from the chaos of the downed tree, all against the backdrop of the quiet sound behind the island.  I gave this painting to my masters thesis advisor –  a truly fantastic person and one of the most genuine people I have ever met.

Henderson Peatlands A and B. Oil on canvas.

Henderson Peatlands. Oil on canvas, 2002. Two peatlands in the Rocky Mountains of Colorado, near the town of Basalt.

Henderson Peatlands.  Peatlands are not particularly common in the central and southern Rocky Mountains, but where they do occur, they offer unique habitat and striking visual contrasts with the surrounding landscape.  I fondly recall the field work for a project in 2002 that required sampling testate amoebae and vegetation in numerous peatlands in Colorado and Wyoming. I was particularly impressed by this vista from near Josephine Lake (3535 m elevation) in Colorado. From the ridge above the lake, two peatlands could be seen to the south nestled in the surrounding deep-green forest.  Informally named the Henderson peatlands, after the nearby Henderson Park Trail, these peatlands contained three species of Sphagnum (S. russowii, S. platyphyllum, and S. warnstorfii) and a diverse association of testate amoebae.

Evening on Au Train Lake. Oil on canvas, 2001.

Evening on Au Train Lake. Oil on canvas, 2001. View from cabin on the edge of Au Train Lake in Upper Michigan.

Evening on Au Train Lake. A portion of summer 2000 was spent in Upper Michigan working with a team of researchers on a project focused on understanding the past water-level fluctuations of Lake Superior, and the impacts of climate changes on coastal wetlands. The peat coring was exhausting, fraught with equipment difficulties and woody peats, and the deer flies were thick. But it didn’t matter….this was Upper Michigan. I have pleasant memories of sitting in front of the cabin, keying out wetland Carex species, and talking ecology and geology with good friends and colleagues. The cabin was only a couple miles inland from Lake Superior, and almost walking distance from our field sites.

Salt marsh and hammock. Oil on canvas, 1998. An area near Cracker Tom Hammock on St. Catherine's Island.

Salt marsh and hammock. Oil on canvas, 1998. An area near Cracker Tom Hammock on St. Catherine’s Island.

Salt marsh and hammock. Another one from St. Catherine’s Island; the location of this scene was very close to where I collected one of the sediment cores used in my masters thesis.  One species of grass, Spartina alterniflora, dominates most of the salt marsh on the east coast of North America.  Although there is low botanical diversity in much of the extensive lower portion of these salt marshes, they are highly productive ecosystems with some very unusual biogeochemical processes.  I can almost smell the hydrogen sulfide when I look at this one.

Tahquamenon Falls. Oil on Canvas, 2000.

Tahquamenon Falls. Oil on Canvas, 2000. A common tourist attraction in Upper Michigan.

Tahquamenon Falls. Another one from Upper Michigan. The Tahquamenon River drains extensive areas of cedar swamp and peatland, making the water dark and humic-stained. During several years of field work in Upper Michigan, this was a nice late afternoon or evening destination when a break was needed. The area is a common tourist attraction, and apparently the location of Henry Longfellow’s “The Song of Hiawatha.”  A nice hike to the waterfalls (there are actually two of them) through hemlock, yellow birch, and white pine forest can be followed by a good beer at the Tahquamenon Brewery.

Canoeing with Clea. Oil on canvas, 2013. Not really a field-site related painting, but a memorable day exploring a wetland along a tributary of Promised Land Lake in the Poconos of Pennsylvania.

Canoeing with Clea. Oil on canvas, 2013.  A memorable day exploring a wetland along a creek associated with Promised Land Lake in the Poconos of Pennsylvania.

Canoeing with Clea. This one is not really a field site but I’ll end with it because it brings back particularly strong positive feelings. It captures a moment spent  with my daughter exploring the riparian wetland adjacent to a small creek connected to Promised Land Lake in the Poconos of Pennsylvania. This was her first time on water, and it was a truly spectacular day enjoying nature.

Happy holidays. Recharge and seek inspiration. Spend some time with family doing what you love.

“The top 75” Wetland Plants

Sparganium eurycarpum, Lemna minor, and Peltandra virginica growing in Pymatuning Marsh of western PA.

Sparganium eurycarpum (Common bur -weed), Lemna minor (Duckweed), and Peltandra virginica (Arrow-arum) growing in Pymatuning Marsh of eastern Ohio.

Plants are the structural foundation of wetlands, and particular species and growth forms are indicative of different wetland types because of their sensitivity to hydroperiod, hydrodynamics, nutrient availability, and other environmental conditions.  The identification of wetland plant genera and species is therefore critically important to research, management, and conservation efforts, and is a fundamental part of wetland delineation for regulatory purposes.

Learning plants as part of a wetland ecology course in the spring semester is challenging, because field trips typically don’t occur until the last few weeks of the semester, and even then not too many plants have emerged from their winter slumber. So in wetland ecology at Lehigh University, students examine, draw, and learn some important wetland plant species and genera from herbarium specimens and other materials, so that they are already experts by the time we go into the field. The act of drawing the specimens forces the students to focus and develop their observation skills, a critical (and often under emphasized) part of the scientific process.

Skunk cabbage and cinnamon fern in Hartstown Swamp of western PA.

Symplocarpus foetidus (Skunk cabbage) and Osmunda cinnamomea (Cinnamon fern) in Hartstown Swamp of western PA.

But what plants should a student know? The list below, what I like to call the “top 75,” is certainly a work in progress. It is composed of mostly of taxa that are typically encountered in eastern North America, and many of the species were selected because we can observe them locally; however, many of the same genera occur in wetlands throughout the world. The plants on the list range from facultative (i.e., found in both uplands and wetlands) to obligate (i.e., virtually always found in wetlands) taxa.  I’d love to hear suggestions for additions, deletions, or substitutions.

Plants that every self-respecting* wetland ecologist should know.

I. Salt-to-brackish marsh plants

Selected student drawings of some common salt marsh plant species.

Some common salt marsh plant species. Drawings by 2013 Wetland Science students (EES-386). Initials of students shown in parantheses.

II. Freshwater marshes and swamps

Submerged aquatics

Some common submerged aquatic plants. Drawings by 2011 Wetland Ecology students (EES-386).

Some common submerged aquatic plants. Drawings by 2011 Wetland Ecology students (EES-386). Initials of students shown next to the drawings.

Floating-leaved plants and floating plants

Some floating and floating-leaved wetland plant species.

Some floating and floating-leaved wetland plant species. Drawings by 2013 Wetland Science students (EES-386). Initials of students shown in parentheses.

Emergents and plants of wet ground

Some common wetland emergents and plants of wet ground. Drawings by students in Wetland Science (EES-386). Initials of students shown in parentheses.

Some common wetland emergents and plants of wet ground. Drawings by students in Wetland Science (EES-386). Initials of students shown in parentheses.

Some wetland ferns and fern allies. Drawings by students in Wetland Science (EES-386). Initials of students shown in parentheses.

Some wetland ferns and fern allies. Drawings by students in Wetland Science (EES-386). Initials of students shown in parentheses.

Swamp (and peatland) trees (several of these are more common in uplands, but are not infrequent in wetlands of the region)

Swamp shrubs

Some common trees and shrubs of wetlands. Drawings by students in Wetland Science (EES-386). Student initials are shown in parentheses.

Some common trees and shrubs of wetlands. Drawings by students in Wetland Science (EES-386). Student initials are shown in parentheses.

III. Peatland plants

Some common peatland plants. Drawings by students in Wetland Science (EES-386). Initials of students shown in parentheses.

Some common peatland plants. Drawings by students in Wetland Science (EES-386). Initials of students shown in parentheses.

*Obviously meant in fun. Seems unlikely that less botanically inclined wetland ecologists really have less self-respect…

Happy Birthday Alfred Russel Wallace

The cover of his 1876 work, “The geographical distribution of animals. With a study of the relations of living and extinct faunas as elucidating the past changes of the earth’s surface.” Needless to say, this is a topic that we are still fascinated with today. Image from: John van Wyhe, ed. 2012-. Wallace Online (

Alfred Russel Wallace, the “father of biogeography,” was born on this day in 1823. Check out a fantastic collection of his work at

And, check out the recent update of Wallace’s zoogeographic regions of the world here.

Palynologist as artist. Artist as palynologist.

Drawing of the pollen of Silene maritima (Sea campion) by Gunnar Erdtman (Erdtman 1954)

Drawing of the pollen of Silene maritima (Sea campion) by Gunnar Erdtman (Erdtman 1954)

Gunnar Erdtman, a Swedish botanist, is usually credited for bringing the technique of pollen analysis (often referred to as palynology) to the world (Fægri 1973, Nilsson & Praglowski 1978,Traverse 2007).  Influenced by a now famous 1916 lecture on pollen analysis given by Lennart von Post, Erdtman’s 1921 thesis was the first major palynology publication in a broadly accessible language (Fægri 1973).  He traveled widely, promoting palynology as a tool to study past vegetation and climate, and developed laboratory techniques still used in studies of pollen morphology today (e.g., acetolysis). Furthermore, he published over 200 papers and several books that established the foundation of the science. But this post is not really about Erdtman’s scientific contributions; it is a simple celebration of what Fægri (1973) referred to as his “artist’s perception of forms.”

“Erdtman was a keen observer and had a capacity for imaginatively demonstrating his findings with the talent of an artist […] and the pedagogical skill of a teacher.” – Nilsson & Praglowski 1978

An 1884 painting by Elias Erdtman, the father of Gunnar Erdtman. (From

Gunnar Erdtman’s artistic gifts and observation skills were likely inherited, inspired, and cultivated by his family. His father, Elias Erdtman, was a well known landscape painter that studied in France at the height of French Impressionism, and there were artists on his mother’s side as well.  He grew up broadly interested in both art and music.

When he wasn’t using his artistic talents to observe, describe, and document the morphology of pollen grains he apparently enjoyed entertaining his friends with his flute playing, and creating surrealistic drawings (Nilsson & Praglowski 1978), like the “self-portrait” below.

According to Traverse (2007), this is Gunnar Erdtman's "self-portrait as a wood gnome."  From the back of Erdtman's 1954 book, "An introduction to pollen analysis."

Gunnar Erdtman’s “self-portrait as a wood gnome,” as it was described by Traverse (2007).  The image is from the back of Erdtman’s 1954 book, “An introduction to pollen analysis.”

Pollen grains are strikingly intricate and beautiful, and Erdtman’s passion for art may have contributed to his interest in palynology.  However, his power as an artist also clearly benefited him as a scientist.  Although almost anyone can learn to identify the general morphological types of pollen, skilled observations are needed to discern the finer structural details of pollen-grain walls and the subtleties of surface texture that enable greater taxonomic precision.  Erdtman was keenly observant of these details.  His observations and meticulously detailed drawings laid the foundation for pollen analysis and established much of the terminology that is still used today to describe pollen features.  I recently looked through Erdtman’s 1954 textbook on pollen analysis, and was struck by the detail and beauty captured in his drawings (shown below).

Selected pollen drawings of Erdtman from his 1954 text, "Introduction to pollen analysis."

Selected drawings of pollen and spores from Erdtman’s 1954 text, “Introduction to pollen analysis.”  Insets adjacent to some pollen grains show a magnified view of the surface texture.  Images collected here come from many different, carefully labelled figures (plates).

Art informs science by focusing the scientist’s observation skills.  Science informs art by providing endless source material for the artist.  And both can inspire each other.

Finally, I can’t resist adding this humorous anecdote:

“Professor Erdtman’s devotion to palynology was unmistakable and expressed itself in many different ways. On napkin holders in various hotels he introduced himself and his wife as “I. M. Pollen” (I am pollen) and “U. R. Pollina” (you are pollina) respectively. As a consequence it was only natural to imagine and discuss during the meal, which pollen types were represented in the mixed salad being served. Thus, a good palynologist should never lose an opportunity to test his or her knowledge in the beloved science of palynology.” – Nilsson et al. (1993)

A sketch of himself riding a birch pollen grain into the sunset done by Erdtman in 1967, six years before he died.  From Traverse 2007.

A quick sketch of himself riding a somewhat (!) oversized birch pollen grain into the sunset. Done on the flyleaf of a book for a friend by Erdtman in 1967, six years before he died. From Traverse 2007.


Literature cited

  • Erdtman, G. 1954. An introduction to pollen analysis. Chronica Botanica Company. 240 p.
  • Fægri, K. 1973. In memoriam O. Gunnar E. Erdtman 1897-1973. Pollen et Spores 15: 5–12.
  • Nilsson, S. & J. Praglowski. 1978. Professor Gunnar Erdtman 1897-1973. Grana 17: 1–4.
  • Nilsson, S., V. Ukraintseva, & G. El-Ghazaly. 1993. Professor Gunnar Erdtman (1897-1 973). Grana (Suppl. 2): 1-2
  • Traverse, A. 2007. Paleopalynology. Second Edition. Springer. 813 p.

Some old leaves…

A few beautiful herbarium specimens collected and pressed in the late 1800s by an unknown collector, and archived in the Lehigh University Herbarium.  The sheets are just labelled “variation in leaves.”  

Herbarium sheet showing variation in leaves. One of several dozen similar sheets collected and pressed in the late 1800s. Photograph: Douglas Benedict.

Another herbarium sheet showing variation in leaves. One of several dozen similar sheets collected and pressed in the late 1800s. Photograph: Douglas Benedict.

Leaping the hedges with a butterfly amoeba

At the Milwaukee Public Museum with the butterflies.

I recently went to the Milwaukee Public Museum with my family.  This destination was carefully chosen because they have a butterfly exhibit, and my 5-year old daughter has developed a butterfly obsession.  In my experience, obsession of this sort is a good thing; in fact, it is the kind of thing that got me into science in the first place.  After I proudly watched her carefully hold and observe the different species of butterflies, and even have a few pleasant conversations with them, I wandered the exhibit and observed the diversity of colors and shapes myself.  There were some really spectacular species.

A butterfly amoeba

Perhaps because I recently had reason to open up Joseph Leidy’s incredibly beautiful 1879 foundational work describing North American testate amoebae (a group of amoebae that construct and live inside tests, or shells), my mind drifted to a statement Leidy made comparing a particular species of testate amoeba to a butterfly.  Apparently the simple beauty and elegance of this particular testate amoeba caused him to radically change his research focus.  He became obsessive about testate amoebae, or rhizopods as he called them. As with his previous research activities (e.g., paleontology, parisitology), his contributions to this new research area were enormous.

The testate amoeba in question was Hyalosphenia papilio.  In Leidy’s words:

“No other lobose rhizopod has more impressed me with its beauty than this one.  From its delicacy and transparency, its bright colors and form, as it moves among the leaves of sphagnum, desmids, and diatoms, I have associated it with the idea of a butterfly hovering among flowers.

A portion of a plate from Joseph Leidy’s 1879 monograph showing some of his drawings of Hyalosphenia papilio….the butterfly amoeba.

Leidy notes that he first observed the species thirty years prior to the publication of his seminal work, and seeing the species brought him fond memories of his explorations in the New Jersey pine barrens:

“Upward of thirty years ago, while examining the structure of sphagnum, my attention was distracted by the movements of a singular animal, whose character and affinities I did not then recognize.”

“This interesting Rhizopod, together with a profusion of other remarkable microscopic forms of both animal and vegetal life, of which many are novel and yet undescribed, recalls pleasing recollections of excursions into the sphagnous bogs, cedar swamps, and pine barrens in the southern region of New Jersey.

His fondness for the species is particularly evident in the next quote.  I can’t help to laugh a bit at the image of  him breaking out the microscope at a holiday dinner party, in order to display his “pets” to his friends.  Perhaps I should try this the next time I host a lab get together!

“I have collected it from early spring to late autumn, and have retained it alive in sphagnum, in a glass case, through the winter.  During the Christmas holidays, I have repeatedly exhibited it, in the living condition, to the admiration of friends.

A portion of a plate from Leidy’s 1865 Cretaceous Reptiles of the United States, showing some vertebrae from Hadrosaurus. (Image source)

What I find most interesting about this, is that Leidy was 50 years old when he decided to pursue this new line research.  He apparently dropped all of his other research endeavors, and focused solely on investigating these simple organisms for four or five years.  This shift in research focus was made by an already famous man who described the first complete dinosaur fossil, as well as many other North American fossils, and was widely recognized as the leading expert in parasitology.

A drawing of Trichina spiralis (now Trichinella spiralis), the  nematode parasite responsible for the disease trichinosis, done in 1887 by Joseph Leidy. Leidy first discovered that trichinosis was caused by a parasite that survived in undercooked meat (Chapman, 1891).  Image source: Collection 532. Joseph Leidy Teaching Diagrams. Academy of Natural Sciences of Philadelphia.

His obituary in the Proceedings of the National Academy of Arts and Sciences suggests that he left his paleontological research because of the extreme rivalries and unfriendly arguments that were shaping the field at the time – rather than get involved in these controversies Leidy may have just moved on.  He certainly would not be the only scientist to do such a thing.  However, according to his own words, it was the beauty of Hyalosphenia papilio that led him to study testate amoebae:

 “September 9th, 1873, the fiftieth anniversary of my birth, a friend, Clarence S. Bement, presented me with a Hartnack microscope, which, from its convenient size and form, I kept on my study table.  From time to time I was led to make observations on Fresh-water Rhizopods detected in sediments collected in the vicinity of Philadelphia.  A year later, in examining water squeezed from sphagnum obtained at Absecom, I observed many individuals of the same singular animal above indicated, but now, understanding its nature, I described it as Difflugia (Hyalosphenia) papilio.  It was the rediscovery of this beautiful form which impelled me to pursue the investigations which constitute the material of the present work.”

Published in 1897, his “Freshwater Rhizopods of North America” is a stunning combination of science and art, and still the most exhaustive description of North American testate amoebae.  For an interesting read on Leidy and the culture of science in mid-1800s North America, pick up a copy of Leonard Warren’s “Joseph Leidy: The last man who knew everything.”  For more on Leidy and a wonderful online version of the drawings included in the 1879 masterpiece, go here and here.

Joseph Leidy with his microscope circa 1870.

Leaping the hedges

The idea of following one’s interests, wherever they take you, is very attractive to me.  Of course, the culture of science has changed dramatically since the 1800s and scientists are generally narrower in focus and constrained by institutional expectations of tenure and promotion.  However, Leidy’s path of scientific exploration still seems a natural one, and I suspect that if more scientists followed his model instead of obsessively chasing promotion or the next big grant, we would collectively learn more about the natural world.

When I interviewed for a faculty position one of the questions that I was asked was to describe my 5-year research plan.  I was prepared for such a question, as it seemed like the sort of thing that I would be asked.  In fact, I carefully designed my research talk (candidates in academia usually “interview” for several days, typically giving one or two public lectures) to incorporate aspects of my long-term research plan.  Seven years later, perhaps not surprisingly, the most interesting science that I have done had little to do with my “plan.”  The projects that have excited me the most have been the things that I or my students have stumbled upon…things that I never could have planned.

I sincerely doubt that Joesph Leidy had a plan.  Sometimes something as simple as a beautiful amoeba, or a colorful butterfly, or perhaps an amoeba reminiscent of a butterfly…. can lead a scientist to wonderful new places.  Hopefully they will lead a certain 5-year old girl to some interesting places too.  The trick is identifying and following your passions (and obsessions), and knowing when it is time to move on to something new.  Leidy knew both…and he said so in the concluding statements of his great work:

“”I may perhaps continue in the same field of research and give to the reader further results, but I cannot promise to do so; for though the subject has proved to me an unceasing source of pleasure, I see before me so many wonderful things in other fields that a strong impulse disposes me to leap the hedges to examine them.””



After posting I ran into this great piece.  A nice example of testate amoebae as inspiration for art.

Genetics of Van Gogh’s Mutant Sunflowers (link)

Genetic Clue to van Gogh’s Mutant Sunflowers Discovered | Wired Science |

Genetic Clue to van Gogh's Mutant Sunflowers Discovered | Wired Science |

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