Missouri Trees Fall Leaves
Community ecology is the study of groups of species living together and their interactions. Scientists studying community ecology ask questions like: Why do some kinds of trees grow together and others do not? Why is this group of species growing in this location? The Smithsonian Forest Global Earth Observatory (ForestGEO) seeks to answer these questions and many more by studying the world's forests. The network includes over 75 sites in over 25 countries where scientists are identifying, mapping, and measuring trees over time. This massive undertaking allows us to witness and record how forests are responding to forces like invasive species, deforestation, and climate change.
The leaves depicted here represent ten of the most common native genera, or the tree community, growing in the ForestGEO research plot at Tyson Research Center. Clockwise from top center: red oak (Quercus rubra), paw paw (Asimina triloba), sassafras (Sassafras albidum), white ash (Fraxinus americana), slippery elm (Ulmus rubra), shagbark hickory (Carya ovata), Carolina buckthorn (Frangula caroliniana), red maple (Acer rubrum) flowering dogwood (Cornus florida), and downy serviceberry (Amelanchier arborea).
​
Missouri Trees Winter Buds
In late summer, North American trees are already preparing for next year by creating buds that will become leaves and flowers the following spring. The buds shelter the future leaf and flower tissue from harsh winter conditions. In the spring, environmental cues of increasing daylength and warming temperatures signal to the tree that it is time for the leaves to emerge. Studying the timing of life history events in an organism's life cycle, such as spring leaf out, is known as phenology. Other examples of phenology include observing when birds migrate, insects emerge, and leaves change color. By recording the phenology of when the leaves develop in the spring, we can better understand how changes in climate impact trees. You, too, can observe phenology in your own backyard and explore data as part of the National Phenology Network.
The ten species in the previous illustration are repeated here in the same order.
​
Invasion I
Invasive species are non-native species that have become harmful to their new ecosystem [1]. Some of the ultimate threats of invasive species include altered food webs, loss of biodiversity, and changes in ecosystem conditions [2]. This piece raises awareness about the threat of invasive species by depicting the relationship between an invasive plant, noxious tall nettle (Urtica procera Willd.), and a native plant, bottlebrush sedge (Carex lurida Wahlenb.), that grow together in a wetland ecosystem. The invasive plant is illustrated as larger than life, with overshadowing serrated leaves and a thick spiked stalk, while the native sedge is depicted as approximately life-size and preserved on an herbarium sheet, alluding to its impeding death. This scale discrepancy highlights the imposing presence of the invasive plant as compared to the fragility of the native plant. The drawing also plays with light and dark, the traditional representatives of good and evil. The native sedge is light in color and lying on a clean background, while the invasive nettle is predominantly dark, with a foreboding backdrop. The contrasts between life and death, large and small, and dark and light draw attention to the struggle between the native bottlebrush sedge and the noxious stinging nettle.
​
Invasion II
“Invasion II” explores a theme similar to that established in “Invasion I,” shifting to an oak-woodland ecosystem where the invasive European highbush cranberry (Viburnum opulus L.) competes with the native shooting star (Dodecatheon meadia L.). This second drawing again warns viewers about the threat of invasive species and the importance of restoration. The two contrasting styles in the drawing characterize the conflict between the native and invasive plant species. The majority of the drawing consists of frenetic multi color overlapping lines which embody the out-of-control nature of the invasive plant. However, this style also suggests hope because the invasive plant seems almost insubstantial and fleeting. On the contrary, the native plant is illustrated realistically, lending to the notion that the native plant is the natural specimen. This solid representation instills confidence that the native will not be over-powered so easily. The juxtaposed linear and solid styles highlight the conflict between the native shooting star and the invasive European highbush cranberry.
​
A Bird in the Hand
Passenger pigeons were once so numerous that people scoffed at the notion they could go extinct, yet severe over-hunting resulted in their obliteration in 1914, over 100 years ago. The 2016 State of North America's Birds listed the cerulean warbler on its “Watch List” [3] which warns us that without concerted conservation efforts, the cerulean warbler may go the way of the passenger pigeon. This illustration explores humans impacts both in biodiversity loss and conservation. Hands provide a powerful vehicle of expression and having a bird in the hand imbues responsibility. The contrasting actions of the hands in the drawing illustrate the dichotomy of abuse and respect: the hands interacting with the pigeon choke, tear, rip, and pull, symbolizing the greed and disregard that led us to hunt them to extinction. In contrast, the hands gently cradling the warbler offer protection, honor, and hope. The warbler and the hands encircling it also provide the light source for the drawing, implying that conservation efforts bring hope. Finally, the passenger pigeon is illustrated in the form of a preserved field skin as a reminder that it lives now only in memory. The piece challenges viewers to consider the role their hands play in destroying and conserving species.
Rhizobia
Mutualism refers to a beneficial relationship for both species involved. Examples abound in nature, such as bees receiving nectar in exchange for pollinating flowers. Some of the symbiotic relationships most crucial to our survival are hidden in the soil beneath our feet: the relationships of plant roots with nitrogen-fixing bacteria, known as rhizobia. The lower left corner of the painting diagrams the process of root-nodule formation with an illustration of the root’s cross section. The red mass of cells represents the bacteroid that forms when rhizobia “infects” the root. The root can then provide nutrients and protection to the bacteria, while the bacteria convert nitrogen into a usable form for the plant. The surrounding area of the painting depicts nodules dispersed in a legume's root system. Circular elements throughout the piece provide a unifying design. The round forms of the nodules are echoed in the smaller cells and the larger white rings. Each ring marks the border of a color palette shift, as though a lens has slid into place enabling the viewer to observe this symbiotic relationship up close. The repeated round forms also nod to the cyclical quality of nitrogen exchanges in the nitrogen cycle. Overall, the repetition of circular forms and the diagram-inspired imagery serve to communicate the symbiotic relationship between legume roots and rhizobia bacteria.
​
Sickle Cell Anemia
Sickle cell anemia is a disease in which a small genetic mutation affects red bloods cells’ shape and ability to transport oxygen through the body. The misshapen cells can clog blood vessels, leading to symptoms such as physical weakness, pain, organ damage, and even paralysis [4]. This drawing highlights the incredible influence that minuscule changes in DNA can have on an individual. In the march of letters symbolizing genetic code, a single red “T” represents a simple mutation that leads to a domino effect of complications. By noting the red elements of the illustration, observers can follow the mutation as it magnifies with each step in the process of genetic material coding for red blood cells: from nucleotides (letters) to amino acids (labelled ovals) to proteins (L-shapes) to molecule stacking (orientation of L-shapes). As a student, it is easy to be consumed by memorizing the details of DNA and proteins and forget that these concepts affect real people. The woman’s presence in the artwork reminds viewers of the humanity involved in biology. Her vulnerable position embodies the suffering that accompanies sickle cell anemia and counterbalances the emotionless letters and shapes. There is a general sense of the disease trapping the individual as the genetic code descends over the figure. Additionally, the tight earth tone color palette reinforces the notion that the figure and the overlay are intrinsically related. The artwork illustrates the process that enables one genetic mutation to greatly alter a life and emphasizes the humanity behind biological diseases.
​
Photosynthesis for Dinner
What does a plant eat for dinner?
​
A healthy serving of thin air (carbon dioxide, represented by blue sweeping swirls) seasoned with nutrients and drizzled with sunlight (vertical yellow beams). And a tall glass of water (underground blue droplets) to wash it all down ...or perhaps up.
Cucurbita
The plant vascular system is comprised of two transport pathways: the phloem and the xylem. The phloem is primarily responsible for the movement of carbon throughout the plant, but proteins, chemical signals, and nutrients also travel in the phloem. The xylem is involved in water transport from the roots of the plant to the leaves [5]. The giant pumpkin (Cucurbita maxima) requires additional amounts of water, carbon, and other nutrients to support its over-sized fruit, and all of these resources must pass through the vascular tissue in a relatively narrow stem [6]. This ceramic mug balances the functional, aesthetic, and educational with surface texture and sculptural elements representing the vascular anatomy of a pumpkin. The leaf extending from the side of the mug illustrates the carbon source for the pumpkin and doubles as a tea bag holder. Depictions of the vascular tissue transporting that carbon to the pumpkin are carved around the mug and emphasized with a deep red tenmoku glaze. The handle echoes the vascular bundle imagery in the third dimension. Since xylem cells are dead at maturity and empty to enable greater flow of water [5], they are carved as holes through the handle.
​
References
[1] http://www.invasivespeciesinfo.gov/index.shtml
[2] https://www.nwf.org/Educational-Resources/Wildlife-Guide/Threats-to-Wildlife/Invasive-Species
[3] http://www.stateofthebirds.org/2016/
[4] Reece, Jane B., L.A. Urry, M.L.Cain, S.A.Wasserman, P.V. Minorsky, R.B. Jackson. (2001) Campbell Biology Ninth Edition. San Fransisco: Pearson Education, Inc.
[5] Taiz, Lincoln, Zeiger, Eduardo, Moller, Ian Max, & Murphy, Angus. (2015) Plant Physiology and Development.
[6] Savage, J. A., Haines D. F., Holbrook, N.M. (2015). The making of giant pumpkins: how selective breeding changed the phloem of Cucurbita maxima from source to sink. Plant, Cell, and Environment, 38:1543–1554.