In this ‘Postcards from the Field’ blog post, Dr Diana Tataru – based at Tulane University – discusses their work on monkeyflowers in the beautiful Yosemite National Park, California! Diana shares plant-level perspectives, top tips for fieldwork, and future studies in the Eastern Sierra Nevadas.
Profile
I am interested in how plants adapt and survive in changing environments! I’m especially interested in extreme environments, like rocky high elevation environments where plants have to survive in extreme temperatures with limited soil and water.
I chose my specific research area (plant evolution) because plants don’t move very quickly, which makes them very susceptible to the environmental conditions that they experience and makes them easier to study! Plants are so important for ecosystem function across the planet, so understanding how they persist and respond to climate change is super relevant if we want to understand the impacts of climate change. On a more specific scale, Monkeyflowers (which are my focal plants) are a super cool system to study because they have adapted to many different environments, but different species can still sometime reproduce with each other. This makes them a perfect system for understanding the intersection of adaptation and how species are formed!
A lot of my research addresses the questions: How does natural selection vary over time and space? And, how does gene flow between species and populations impact response to varying selection? Often we can view species and organisms as static or unidirectional entities, but the reality is that everything is always in a process of change- sometimes species can become more different, and sometimes they can become more similar! I am interested in the drivers and nuances of these processes of change.
Where in the world are you?
Much of my field work is located in the beautiful Yosemite National Park, California. My field sites are places where Monkeyflowers grow, which can range from wet and lush meadows, to rocky granite outcrops, to the vertical face of El Capitan!
When I’m running my field experiments, a day in the field looks like waking up early in the morning to drive an hour to the first site. Yosemite is very big and often the field housing is far away from the field sites. Then, myself and a field technician will survey the experiment for flowering and death of up to 4000 plants we are tracking. We plant out these experimental monkeyflowers with tweezers at the beginning of a growing season in little blocks marked by toothpicks, and visit them every other day to track their growth. When they flower, we measure metrics like flower size, plant height, and leaf shape! At the end of the season, we collect the plants once they have died to count how many seeds they produced. This way, we can track how different plants look and reproduce in different natural conditions. Tracking growth in these plants means looking at every plant every other day and recording how it’s doing. You can imagine this takes a long time, and we’re often out there on our hands and knees all day staring at tiny plants!
I always feel most connected with the land when I am belly-down on some cold snow melt water, planting monkeyflowers with tweezers in the moss. Spending all day at their eye-level is such a different perspective, and then sometimes to have a Great Grey Owl fly overhead or hear a black bear thrash through the forest nearby, I feel so small!
Some challenges that I have witnessed at the study sites is that the growing season for these plants can be super short. Sometimes, the plants germinate too early and it will freeze or snow, sometimes the snowmelt dries out to quickly and the plants die before flowering! It feels like every year I am holding my breath for the humbling lesson that nature will teach.
My field sites are some of the most beautiful places I’ve ever been, and the monkeyflowers always grow in the best time of the year, when the sun is shining strong and the water is trickling over the granite rocks. I have a lot of hope for these monkeyflowers because if even if they experience an intense year, with heavy drought or fire that limits the population size, they can bounce back in the following year! These plants also can respond very quickly to varying conditions and will have different traits and levels of gene flow in response to environmental variation, which leads me to think that they will be able to adapt to changing conditions.
Tips for Fieldwork
I touched on this earlier, but the timing of experiments can vary so much from year to year depending on snowpack and snow melt, and we often don’t have a great picture of how it will go until very close to the beginning of the season. This is especially challenging because we have to move across the country from New Orleans (where Tulane University is), and also begin the process of growing the experimental plants at least three weeks before putting them in the field. This is because the plants require cold stratification to germinate, which looks like putting them in a fridge for two weeks, and then another week in the warm greenhouse to induce germination. In some ways this can be a fun challenge, because I start tracking snowpack accumulation early on in the year and feel some connection with the seasonal life that these plants experience. I also have learned to start growing plants early, and always save enough seeds to plant an extra emergency round at the end!
What I love most about field work is the connection and curiosity with the system that it cultivates. It is so special to experience the same conditions that these plants experience, and watch them grow and die. All of my most fruitful scientific ideas have come from observations and questions that I have had when being with the plants in their natural environment.
I rely heavily on National Park Service staff to approve and assist with my research! From permitting to site access, none of this work could happen without the current and past stewards of this land. One of the most fruitful collaborations I’ve had is with the NPS climbing rangers, who have helped me identify and collect samples from Monkeyflower populations all across El Capitan. They are already planning these climbing expeditions to check permits and clean up trash, among other things, and it’s really cool to tag along and incorporate science into their technical endeavors!
The Future
My dream study site it the one I’ve been studying! I think that there’s something very special about developing lasting connection and knowledge in a place, and I’m just excited to continue to nurture that relationship and continue to learn in these beautiful and every-changing mountains!
I am starting a position with the US Geological Survey to study adaptation of plant and cryptobiotic crust communities to disturbance in the high elevation deserts of the Eastern Sierra Nevadas. After so much time studying monkeyflowers growing on moss and getting curious about how the substrate responds to the environment, I finally get to take a deeper dive into the moss!
