As the three weeks of my externship at the Echinacea Project comes to a close, I’ve learned a lot about the research process and the different stages of a scientific investigation. After coming up with my main research question about density and seed predation in Liatris a couple of weeks ago, I have since been working on cleaning and randomizing Liatris, as well as quantifying seed predation in order to analyze the relationships I wanted to investigate.
After going through all the steps of getting my data ready for analysis, I got to do some data visualization and statistical tests to fully analyze the results of my project. This was done in R, where I make several graphs and ran statistical tests such as t-tests and generalized linear models.
After getting to analyze my data, I put together a presentation summarizing some of my findings and my thoughts about them. To summarize, my main research question was investigating whether the fire-induced density of flowering Liatris plants influenced seed predation, and I hypothesized that burning would lead to higher density, which would lead to higher seed predation. I found that burning did in fact lead to a higher density of Liatris plants, but there was not a significant relationship between nearest neighbor distances and seed predation, with only a very slight negative relationship between the two. There was a steeper relationship between the two in just burned plots versus unburned plots, which I thought was interesting, although I am unsure about why this is the case.
Overall, I found that the reproductive benefits of fire do not seem to be outweighed by the threats posed by seed predation, which is good news for those that want to use fire as a tool for prairie management and conservation. My entire presentation, with background information and the graphs I used, can be found below!
Overall, this experience has been very insightful into the world of scientific research, as well as all of the methodologies and tools necessary to successfully complete a project and gather meaningful data. I’ve learned first-hand the importance of things such as random, unbiased samples, having a thorough, detailed protocol, and having organized workflows and data collection methods. I have also had the opportunity to meet and talk to people pursuing ecological research and learn about that process, which has been super helpful. I think that one of my biggest takeaways from this externship is that you don’t have to have all of the answers and that there are always more questions to investigate.
Alondra, Connor, Maeve, and Marina finished their mini-internships with us. It was a great experience for them and us. We appreciate their contributions to science and conservation and they gained valuable experience. As part of their plant biology class, Alondra, Connor, Maeve, and Marina, who are juniors and seniors at Lake Forest College, worked on two projects to assess effects of prescribed fires on reproduction in Echinacea. In the lab, they gained hands-on experience in seed biology over three Wednesday afternoons, including cleaning, scanning, counting, developing hypotheses, and data management. To test their hypotheses, they developed a dataset and summarized their results. In class they presented posters and they are attached here. It was a wonderful mini-internship–thanks to Alondra, Connor, Maeve, and Marina, as well as Prof. Westley!
It’s Emma Greenlee, reporting from Northfield, MN on my presentation at the Winchell Undergraduate Research Symposium! This is a research symposium for students in STEM at Minnesota colleges to present their research, and I presented my work from my independent project with the Echinacea Project last summer (see this flog post for more info!). The symposium was on zoom, naturally this year, and students presented in small groups for 10 minutes each. So pretty low stakes but a really good opportunity to practice presenting to an audience and it held me accountable to finish a few data analysis and visualization things I had been needing to do for my project. This e-conference made me think I could handle and enjoy the real thing, which is cool!
That’s all for me for now, just a month left at Carleton before I’ll be heading to Nevada on a Conservation and Land Management internship doing native seed collection with the Forest Service.
Peace out for now FLOG but I don’t think you’ve heard the last of me yet!
This fall, I had the opportunity to present a poster about my recent field research on pollen interference at the Carleton College Summer Research Symposium on October 19. This poster focused on the parts of my experiment that tested whether false sunflower (Heliopsis helianthoides) pollen interferes with reproduction in Echinacea by causing styles to shrivel. My findings suggested that this style shriveling results from a cooperation between dame and sire identity, such that applying pollen from any one false sunflower might succeed in causing style shriveling on one Echinacea plant but not another. This poster summarizes some interesting and promising early results, and I am looking forward to analyzing the presented data further in the coming months. Thank you to everyone at the Echinacea Project who helped make this experiment possible!
Tate Rosenhagen, an intern from Lake Forest College who spent four week days with the Echinacea Project doing seed research, finished a poster with findings about Echinacea reproductive output and achene weight. We really enjoyed having Tate around, he brought a lot of positive vibes and insightful questions to the lab. Tate is great!
Long time no see! I am a grad student at the University of Colorado now, but thankfully I have still had plenty of time to work on some Echinacea work. Last week I got to present at Botany in beautiful Tucson, Arizona 🌵.
First I presented a poster about fire and Echinacea demography. This is something we started in Chicago and Stuart, Amy Dykstra and I have been working on since. We used demap, the seedling search dataset, and the seedling recruitment experiment dataset to estimate vital rates (survival, flowering, and recruitment) within several Echinacea populations. We then estimated how these vital rates varied with fire. To see how these changes in vital rates affected actual population dynamics, we then constructed matrix models to estimate the average growth rates of several remnant populations under various fire frequencies. Finally, to see which demographic pathway was primarily responsible for changes in population growth, we decomposed the changes in population growth rates under different fire regimes into contributions from each vital rate’s response to fire. We used Bayesian modeling to estimate the vital rates. Stuart, Amy D. and I are putting the finishing touches on a manuscript for this project, so keep your eyes open!
I got some good questions from people at the conference. One is: would seed addition help bolster growth rates? Very interesting question – I think it probably would in populations with high juvenile survival, given that under these circumstances higher recruitment has the largest contribution to population growth. Another person asked about climate change and whether I thought the Echinacea range was likely to move north with warmer temperatures. I can’t answer that question but we did use climate data in our models; climate was warmer and wetter in our observation period than they were in the 100 years prior, and these covariates were featured in some of our models. It would be fun to incorporate climate change into estimates of vital rates and population growth.
I also gave a three-minute lightning talk to briefly present an idea I have had since I was in Chicago in 2017. Amy, Jennifer, Gretel, and Stuart have done some prior work looking at synchrony, mating opportunity, and mating success in Echinacea. I have been curious about whether populations exhibit nested structure in their flowering schedules, i.e., whether or not individuals which flower less often flower in the same years as plants which flower most often. There are some interesting potential consequences of deviation from non-nested structure. Hopefully I have time to study this in Colorado.
Also of note: Jennifer gave an awesome talk synthesizing a lot of the pollinator work done in the Echinacea system the last several years. It was great to see so many facets of Echinacea pollination discussed together. One of the most interesting parts of this talk was Mia’s poster, looking at the diversity of male pollen donors on bees, and how they varied by pollinator species. I remember when Laura was collecting this data in 2016. She was so good at wiping! Very cool to see final results for this project!
Otherwise, there were some great talks and posters. A couple of good ones: Joseph Braasch from Katrina Dluglosch’s lab at the University of Arizona talking about community shift with climate change and Jessa Finch (from CBG) talking about how gene flow affects early life stages of milkweeds. Maybe the best talk I saw came from a student in Julie Etterson’s lab at UM Duluth talking about how seed collections for restorations is artificially selecting for traits. Very cool question!
I’m glad I was able to make it out to the conference. Huge thanks to my advisors Brett Melbourne and Kendi Davies for allowing me to work on this project for the last two years. Also thanks to the BioFrontiers Institute at CU Boulder for providing me funding while I worked on this project, the United Government of Grad Students at CU Boulder for funding my trip to the conference, and friends at CU Boulder and Colorado State who allowed me to drive down with them and crash in their hotel rooms in Tucson. Hope to see everybody at ESA in Louisville, KY later this month, where I will have a poster about some of the non-Echinacea work I am doing in Colorado.
Dining in Tucson: Mexican food, no, waffles, yes!Ipomopsis longiflora I spotted on the drive back outside Taos, NM. The CO crew identified this plant with a key while I tried to find a gas station.
In general I am interested in how plants interact with their surroundings, particularly the other plants in the system. I worked with Team Echinacea last year on a project attempting to determine how many pollen grains it takes to set a seed. Turns out it doesn’t matter and on the head a floret is that determines seed set! In the fall/this summer I will be starting my senior thesis/IS (independent study) with a plant called Coral Bean (Erythrina flabelliformis) in Arizona. I will be investigating how mating is affected by the amount of flowers on a plant and geographic/temporal distance between plants.
Personal Interests:
I am now a senior biology major with a minor in environmental studies at the College of Wooster. I am from Buffalo, NY. At school I am former president of knitting club, but recently I have really gotten into embroidery. I also enjoy spending time outside with my dog named Ellie.
Me last summer feeding one of the goats buckthorn
MEEC 2019:
On a different note another student from Wooster (Nate) and I presented at MEEC. We presented a poster on my pollen to seed ratios from my research last summer. As it turns out, pollen is not the limiting resource to determine seed set but instead the location of a floret on the flower head.
To take a quick break from all the posts about MEEC 2019, here’s members of Team Echinacea presenting somewhere completely different! Like Tris, Julie and Sarah joined Team Echinacea in November as part of the Carleton extern program. While here, they worked with Lea on her work on Liatris and Solidago, using many of the ACE techinques that we normally reserve for Echinacea. Specifically, Sarah and Julie are looking at how fire at Staffanson Prairie Preserve effects the flowering and seed set of the various Asteraceae there.
Much like Lea is finding in her modelling of these two species, Liatris has a fairly strong interaction with fire, while solidago does not seem to have any interaction. The mechanisms behaind this a certainly still unclear. Julie and Sarah presented these findings at the Winchell Conference – a conference for undergraduate research at their home institution – Carleton College.
Julie and Sara at their poster
Title:Interaction effects of burn treatment and floral display on reproductive success within Liatris aspera and Solidago speciosa
Presented at: 2019 Winchell Undergraduate Research Symposium at Carleton College in Northfield, MN
Like Tris, I am also presenting work related to pollen limitation in Echinacea. For my project, I simply tried to find whether pollen limitation is present in Echinacea or not. What I found – it’s not (though, after presenting this poster, there has been some controversy!). It just seems that echinacea produces as much seed as it can up to a certain limit, then stops, regardless of whether more styles were pollinated.
I went a little unorthodox with the way I designed this poster. Instead of the normal “wall of text” design, I instead opted to use the “better poster” design created by Mike Morrison. I really liked using this! It was so incredibly easy to make, and it really facilitated great conversations with everyone who stopped by poster slot #37. I’m very much looking forward to using this poster design each and every time I present from now on.
Michael with his pollen limitation poster
Title: No evidence of pollen limitation in the long-lived perennial Echinacea angustifolia
Presented at: MEEC 2019 at Indiana State University in Terre Haute, IN
