I spent the week at Palo Verde Biological Station in Costa Rica for the OTS Tropical Plant Systematics course. This site is a stark contrast to the high elevation, cool forests at Cuericí, but has a variety of intriguing forests and habitat types. Now the wet season, these seasonally dry forests are green and full of life. The biological station looks south on a large marsh, and the Rio Tempisque. One of the class hikes involved examining the diversity of aquatic plants in the waist deep marsh. Vachellia collinsii (Saff.) Seigler & Ebinger This plant is one of many with a fascinating ant symbiosis biology. This provides to the ants food via nectaries on the petiole, as well as a home in the large swollen thorns. These ants aggressively defend their host, and even weed out the competition in the understory. Guazuma ulmifolia Lam. Recently placed in the subfamily Byttneroideae of Malvaceae, G. ulmifolia has peculiar stamen-like filaments that are actually modified petals. Relationships between subfamilies in Malvaceae remains obscure, and there is still much work to be done in this group. Polystemma guatemalense (Schltr.) W.D.Stevens Tomorrow I'll be visiting a mangrove to do some botanizing, before heading to the La Selva Biological Station.
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I have just received the William H. Danforth Fellowship in Plant Sciences! This fellowship provides me with four years of full stipend support along with additional funds for travel and research expenses. I am so grateful for this opportunity which represents a huge step forward in securing the funding needed to complete my research. This stipend support in conjunction with I-CARES funding will enable to me to probe the genetic basis of lipid composition across Camelina and investigate the influence of polyploidy on the lipid biosynthesis pathway.
I've had the pleasure to travel to Las Cruces and Cuericí biological stations in Costa Rica as part of the OTS Tropical Plant Systematics course. During the past couple of weeks I spent time at these sites attending course lectures, collecting plants, herping, and learning new computational skills. I will now spend a week in Palo Verde National Park before spending nearly two weeks at La Selva Biological Station. Here are some of the highlights (and plants) of my trip so far: This is one of the many Neotropical Green Anoles wandering about the gardens at Las Cruces Biological Station. Centropogon ferrungineus (L.f.) Gleason The cloud forests around Cuericí are filled with a diversity of flora, and the mix of primary and secondary forests allows for interesting comparisons. Kohleria tigridia (Ohlend.) Roalson & Boggan Romanschulzia costaricensis (Standl.) Rollins This is a very interesting Crucifer native to Costa Rica and can be distinguished from the endemic R. apetala by having reduced white petals and narrow fruits (~1mm wide), whereas R. apetala is of a shrub-like habit, lacks petals, and has wider fruits (3-4mm). A view from the old oxcart trail in the Costa Rican Talamanca páramo. Elaphoglossum hoffmannii (Mett. ex Kuhn) Christ It's a real pleasure to be taking the OTS Tropical Plant Systematics course with Ptedirophyte (fern) expert, Robbin Moran from the New York Botanical Gardens. With Robbin's supreme enthusiasm, we hunted down this extraordinary iridescent Elaphoglossum in the Talamanca páramo! Pachyphyllum hispidulum (Rchb. f.) Garay & Dunst.
This little orchid grows inconspicuously on trees in the páramo. Some branches host half a dozen of these, and to my surprise the populations were quite large. Orchidaceae is one of the most diverse families that inhabit the páramo and luckily many species of epiphytic and terrestrial orchids were in bloom! David Goad of the Olsen lab recently had his research featured in the St. Louis post. Click here to read the article about David's research on Paspalum vaginatum, and check out his website here.
It's my first day in Costa Rica for the Organization for Tropical Studies (OTS) graduate course in Tropical Plant Systematics. After a quick trip to the University of Costa Rica campus and the Museo Nacional, we explored the mercado central of San Jose. I stumbled across this medicinal plants vendor who was selling bundles of dried Lepidium, which unbeknownst to me, has some suspected medicinal values. Regretfully, I didn't ask how much each bundle cost, but it's a miracle they sell at all with all of the weedy Lepidium growing throughout the streets of San Jose.
I just finished my second rotation (in the Kellogg lab), where I was characterizing Sorghum meristem development. I have always wanted to do Scanning Electron Microscopy, and learning a new technique is always a welcome change of pace. As a bonus, I gleaned a wealth of Poaceae knowledge and an appreciation for the immense diversity in the family - plus, I got to take some really cool pictures! Above is an image of a Sorghum pedicel, with a dense indumentum of elongating trichomes.
It shouldn't come as a surprise that production of animal based food is more resource intensive than that of plant based foods, after all it is plants that the animals consume. This graph illustrates the disparity, but especially highlights the huge difference in land-use (green bars) between the two categories. In a world grappling to manage a changing climate, and seeking solutions to provide food for 9 billion people by the year 2050, it seems obvious where cuts should be made. Yet, consumption of meats is only projected to increase. This is already placing strain on the world's limited arable land suitable for agriculture, and short of social and cultural shifts, the burden will be carried by scientists seeking solutions to enhance agricultural productivity while reducing environmental impacts.
The Olsen lab visited the Cahokia Mounds State Historical Site this weekend, and it was a good opportunity for me to learn about a culture so often forgotten, yet so close to home. The Mississipian culture was one that thrived in North America; they used tools, practiced agriculture, and most notably, built mounds. The inhabitants of Cahokia would dig out basins for their houses to sit atop, which would provide a more favorable indoor climate in both summer and winter, and they would deposit this earth atop one of many mounds being constructed in the city. The largest, Monks Mound, was supposedly constructed over 300 years. This is no small feat for a people without horses or the wheel.
The location of Cahokia was superb for agriculture, and they grew previously wild North American crops such as sumpweed, goosefoot, knotweed, little barley, maygrass, sunflower, and squash. However, it is thought that the introduction of maize from Central America was what allowed the people of Cahokia to increase in population and create a vast and powerful city. A solar calendar, known as "woodhenge" comprised many large wood posts, set in a large circle; it was used to mark solar fluctuations and the start of winter and summer. This is a powerful component of agricultural societies, as planning for sowing and harvests with a calendar allows for more predictability and food security. Unfortunately, by around 1400 CE, after years of decline, the city was abandoned, long before the arrival of Europeans. The reason for the decline is attributed to many factors, although one seems to make the most sense to me - deforestation. Cahokia required wood for burning in the winter, and for constructing buildings and walls. Without horses or the wheel, this means that those harvesting trees would have had to walk to this resource, but as they harvested more and more, the edge of the forest would have become more distant, and eventually out of reach. The largest problem now facing Cahokia (and similar archaeological sites), is the threat of development and neglect. One archaeological site, now forever lost, is that of "Mound city", which is located in present day St. Louis, the mounds of this site were used as fill in construction projects during the development of St. Louis in the 1800's. Many interesting phenomena can be observed in the field; some are well documented, others unknown. As far as I know, little is known about biotic interactions with Camelina species, so I'll share of few of my observations from the field: These wasps have built a nest on the stem of a (highly) mature Camelina laxa plant in Armenia. I had noticed this a couple of times, but luckily there were always plenty of other plants to sample in the area so I never had to risk a confrontation. It makes me wonder, though, why these wasps chose such a lanky, annual plant to build a nest on, as opposed to a more permanent structure. I suppose this could be an example of an accidental commensalism; the Camelina is protected from herbivores, and the wasps get a nice (?) nesting place. Spiders especially love to set up shop on Camelina. We frequently found spider webs covering the branches and infloresences of Camelina, and webs spanned several plants to form an effective insect net. Camelina's dispersal mechanism of simply dropping seeds in the vicinity often leads to small patches of related plants growing in close proximity to each other, making a perfect scaffold for these spiders. Some (Carpocoris?) shield bugs hanging out, in fact, they seemed to enjoy sitting on Camelina fruits. But why? It didn't appear that they were feeding through the fruit valves, although this would be the most obvious explanation. Despite the many defense mechanisms of Camelina (rigid trichomes and glucosinolates), some herbivores are just too formidable.
I was first exposed to the great diversity within Brassicaceae while in Turkey in 2012. Pictured above (center) is a specimen of Coluteocarpus vesicaria (L.) Holmboe, which is an interesting plant by all accounts. Its large inflated fruits appear alien on this steep slope in Eastern Turkey. Also visible is Aethionema sp. (center right), which has phylogenetic and evolutionary importance; the tribe Aethionemeae is sister to the rest of Brassicaceae.
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AuthorJordan Brock Archives
November 2019
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