Exciting news! My very FIRST *first author **peer-reviewed publication is officially published in the journal of Ecological Entomology. It is especially exciting because I was able to use grant money to make the article open access, so anyone can read it without hitting a paywall.
Here is the link! https://onlinelibrary.wiley.com/doi/full/10.1111/een.12928
Despite this paper being free to read, the way we communicate science in journal articles is completely inaccessible to anyone outside of our little branch of science. So, I am going to create blog posts that explain my work. I am also going to share the research journey that led to this publication, because in science (and life) we only see the shiny beautiful products of research, without all of the failed experiments in between. Itâs just like Instagram. Hopefully, that will help some of my troubleshooting scientist friends, as well as anyone else, see exactly what goes into these papers!
*A first author publication means that author did most of the research + writing + creative input. I conducted all of the experiments in this paper and went back and forth with my advisor (final author) on numerous revisions while writing it up. The other two authors provided me lab space, trained me to use the equipment, and assisted with the statistical analysis and interpreting the results.
** Peer-reviewed means I sent it to a journal and several (in this case, 3) anonymous scientists in the field read the paper and decided it was valid enough to publish. The process is long. We submitted in February for the first time and went through three rounds of revisions (addressing edits from the anonymous scientists/reviewers). It can take way longer in other journals! This is how scientists keep each other in check and why we say you should trust peer-reviewed studies. The work is heavily critiqued and continues to be critiqued when they are published. This is how some studies, (like one that concluded vaccines cause autism) are âredactedâ or removed from journals.
TL/DR Results:
(Too long, didn't read)
1) Choosy aphids choose well-watered plants! Aphids preferred well-watered plants and mildly drought-stressed plants over highly drought-stressed plants. However, they canât tell the difference between/didnât choose to differentiate between well-watered and mildly drought-stressed plants.
2) Aphids didnât feed differently on stressed plants. They were just as able to find a good spot to stick their straw in and slurp up that plant sap on drought-stressed plants.
3) Aphids pooped LESS on stressed plants (experiencing ANY level of stress).
Interpretation: Aphids make host-plant decisions based on plant water availability, and it might result in them avoiding highly-stressed plants/fields. Aphids feed for the same DURATION on stressed plants but poop LESS. This could mean their feeding rate declines on stressed plants. If you drive for 30 minutes at 50 mph vs 70 mph, you arenât getting as far. All in all, even really small losses of water in plants influence aphid behavior.
My research, generally:
Overall, my PhD research focused on how climate change may influence insect populations that are pests in agricultural systems.
Which insect do you study?
Aphids! They are a pest in every cropping system you can think of. There are a bunch of species of aphids, and they come in all sorts of colors. They are especially damaging because they can clone themselves, so they just sit eat and pop out babies for their entire life without even having to stop to mate. They feed with this little straw to suck up that sweet, sweet plant sap â and actually can give plants diseases the same way mosquitoes give humans diseases.
1) Pea aphid giving birth while eating #multitasking (wiki commons) 2) Yellow milkweed aphids (wiki commons) 3) Adorable & floofy woolly aphids (Ian Boyd) 4) The bird cherry-oat aphid (Bugwood: Adam Sisson) - my aphid of choice!
Climate change?
There are a lot of things to study with climate change, but I am focusing on droughts. Drought events are increasing in frequency and intensity around the world due to climate change, and it costs farmers/growers billions of dollars annually.
Connect the two?
There are predictions that drought might lead to more outbreaks of insect pests, especially the kinds that feed on plant sap like aphids. This is because of predicted changes in the plant nutritionally that might benefit the aphid. However, it seems like experiments find mixed results -sometimes aphids do better or worse? In addition, exactly how little water the plants have available makes a difference. If the plant is on the verge of death because it hasn't been watered in a week, that could be a very different scenario than a plant without water for 2-3 days. So, I use multiple levels of drought stress in my research.
This paper:
If plants are drought-stressed, does that influence the way aphids interact with those plants?
1) Can aphids tell the difference between plants that are well-watered and drought-stressed? Do they prefer one over the other? If aphids prefer to walk onto/feed on one plant, that could influence how many aphids end up in a drought-stressed field.
2) Do they feed differently on stressed plants? Aphids may take longer to stick their straw mouth into drought-stressed plants, and any time spent not feeding is resources lost for having babies.
3) Do they POOP different on stressed plants? Thatâs right. What goes in, must come out. If they poop more or less when feeding on a plant, it says something about how efficient they are at eating the plant.
The Research Journey:
The long and winding road that leads to a publication (if you are lucky)
Things often do not go as planned when conducting research â especially with live organisms who do their own thing.
1) Aphid choice experiment
Get aphids to pick between plants. Limitations: Leaves must remain connected to plants (because of plant resource circulation/sap tension). Aphids must not escape. This was the first experiment I attempted in graduate school!
Attempt #1 (Fall 2015): Put two leaves inside of a petri dish, set aphids in the middle, and see where they end up a few hours later. We call this a two-choice experiment.
Result = Failure. Aphids made the ever present third choice to escape the petri dishes.
Attempt #2 (Fall 2015) Hot glue time. Create insect cages out of food storage containers with bridal veil material on top to allow ventilation. Cut holes in the sides to slide leaf through and stuff with cotton to prevent aphid escape. This will work for sure (look how confident I am in pic 2).
Result: Aphids did not cooperate.
Attempt #3 (Spring 2016): MAYBE the question should be whether or not they leave a plant in search of a better option. What if I set them up on a leaf and saw if they left if the leaf was drought-stressed? (Set-up shown above).
Result #3 Aphids are very complacent -did not want to leave.
~Give up for about 2 years~
Attempt #4 (Spring 2018): Brilliant, weathered graduate student wonders âWhat if I just give them a whole plant to choose between in a bug dormâ? I constructed a bridges out of old Raisin bran boxes from my partner, set them between the plant stems (they like to crawl up), and put aphids in the middle.
Success! Repeated one more time. Success!
2) Aphid Feeding Behavior Experiment: Creating aphid circuits!
I traveled to Fort Wayne, Indiana to learn how to use this badass scientific method called the electrical penetration graph technique. Essentially, you put a probe in the soil a the base of a plant and connect it to this small probe that you glue to the back of an insect. Whenever the insect makes contact with the plant with its mouthstraw â the circuit connects and a signal is generated that is amplified and converted into a specific waveform based on what part of the plant the aphid is feeding on. Cool diagram from Wikipedia below
Getting the probe on the aphid is tricky. Basically, you make this little fishing pole out of a nail, copper wire (pole), fine gold wire (line), and silver glue (the bait) and whip the glue onto the aphid. It reminds me of this magnetic fishing game I used to play growing up.
Then, you record the generated signals for 8 hours. I had to plan my time carefully on my weekend visits to make them as efficient as possible (typically, I would drive the 7 hrs to Fort Wayne after my morning class on Thursdays, and drive back sometime on Monday).
To know what is happening, you have to go through each 8 hr file and label each waveform by hand. It is a long process, but I kind of enjoy it. Output pictured below with labels (each dotted line is 1 second)
This technique goes haywire A LOT. To get the number of successful runs that I could use for the paper, I ran 18 trials (7 plants at a time, which is 126 plants) to get a total of 40 usable plants (Thatâs a 32% success rate right there). BUT it was so cool, and I get to dive into this technique more in my new postdoctoral position.
I ended up taking 5 separate trips to Fort Wayne in the spring of 2018. It worked out well because my parents live an hour and a half away, so we were able to visit a little while I was there. That was really nice.
But to be real, this was the most exhausted that I have ever been. Aidan was traveling to Winona, MN very regularly at this point, and our trips would overlap in the worst way. I would leave on a Thursday, he would come home that Friday, and I wouldn't be back until Monday night. I was just running as many EPG experiments as I could while I was there, and studying for my comprehensive exams while I was waiting for each EPG to finish. It was a very emotionally "numb" time.
Aidan snapped this photo of my setting up a run on the one trip he was able to join me on. This whole crazy science life is not always easy.
3) How the heck do you measure aphid poop?
This was actually the easiest experiment I did in all of my PhD. It was also the last one, so that might be part of it.
Literally, I put wax paper under aphids for 24 hours, brought the paper to the lab, and counted the drops under a microscope (accounting for size differences). Easy peasy- the aphids conveniently like to feed on the underside of leaves, so the drops just fell right to the bottom. Pictured: Set up, wonderful technicians, and some large drops of honeydew.
So there you have it! Three separate experiments spanning 4 years. Research takes a lot of patience and creativity - but the end result is really rewarding. Thanks for reading! Stay tuned for more publication breakdowns :)
