From the desert to the arctic: Plant.ID conquers USA
Last summer, in July 2019, we set foot in the New World: USA! We had two purposes in mind: firstly, presenting our work at the annual Botany conference; secondly, sampling specimens for Anne-Sophie’s project. We found ourselves confronted with big contrasts in this massive country: contrasting climates, contrasting landscapes, contrasting vegetation, contrasting aspects of the job…! The first part of our trip brought us to a semi-arid subtropical climate in Tucson, Arizona, while we were flying to a subarctic climate in Fairbanks, Alaska, only 10 days later. Tucson is surrounded by the lushest desert, the Sonoran Desert, and its characteristic vegetation is dominated by legume trees (Palo Verde trees) and the iconic columnar cacti (Saguaro cacti), among 2000 other species. Our Alaskan peregrination was surrounded by a boreal forest, characterized by pine, spruce, and larch. The situations experienced during a conference and a field trip are rather different: while in Tucson, we were confronted with the opportunity to networking, with many stimuli and solicitations during the conference, always surrounded by scientists, the field trip was rather lonely, with no other networking possibility than bears, guns aficionados, and camping-car experts!
The Botany conference “Sky islands & Desert seas” - 27-31 July 2019 - Tucson, Arizona, USA
Yannick presented his ongoing work on a project focusing on the evolution of the succulence syndrome in the genus Aloe and its role in the evolutionary diversification of this species-rich and widely distributed group of desert plants. The main aim is to accurately quantify the succulence syndrome in Aloe and he presented the methods for this. In the far-away corner of a massive conference hall with over 160 posters, fellow succulence enthusiasts presented their posters, mainly to each other, but leading to some nice new collaborations. Bengt Oxelman, Anne-Sophie’s supervisor, and Christoph Oberprieler organized the colloquium “Species delimitation in polyploid complexes”. Anne-Sophie seized the opportunity to give her first talk at an international conference, in a room packed with polyploid fanatics. She discussed why long read sequencing is the solution to facilitate polyploid species genome assembly, and her current work about long reads sequencing from herbarium specimens. After a fruitful conference, it was time to leave the drought of Tucson and its 45°C to arrive in rainy Fairbanks where it hardly reached 16°C.
The Call of the Wild
126 years after Jack London and his famous Canidae hero, Plant.ID set foot in Alaska. Four species of Silene sect. Physolychnis are present there: S. involucrata, S. ostenfeldii, S. uralensis, and S. soczavana. A significant part of the area is covered with boreal forest without roads and consequently not accessible by car. Therefore, the only possibility by car is to follow the highways covering only the eastern part of the region (see map). Moreover, in Alaska, the distances between towns are huge, without anything in between but bears. Wild camping is thus not encouraged, and you need to bring enough fuel of course. After landing, collecting the rental car was our priority. We were confronted to an unexpected reality after discussing with the car rental company: most of the roads we planned to drive were not covered by the car insurance, and thus forbidden. However, most of the specimens we wanted to collect were distributed along these forbidden roads. Plants don’t follow insurance agreements, neither did we…
Once the sampling plan was realistically adjusted, as it is often necessary before a field trip, it was time to hit the road. We left Fairbanks with the feeling that nothing could stop us, with a busy schedule ahead: Fairbanks -> Delta Junction to sample a population of Silene involucrata and S. soczavana -> Tok for S. ostenfeldii -> Chicken for S. involucrata -> Tok again -> Glenallen -> Anchorage for S. uralensis and S. soczavana -> Cantwell for S. soczavana -> Fairbanks. However, the sampling results were extremely disappointing. We found “Silene-looking” specimens in only one location: they were all in a bad shape, mainly with dead leaves. Once we found its leaves, it actually turned out to be a monocot (see picture). Several hypotheses might explain this: the summer in Alaska was particularly warm, leading to a very early blooming season. Moreover, most of the sampling coordinates were from the early-mid 20th century, with some locations non-reachable because of a change in the area urbanization, for example.
Any biologist with significant field work experience will tell you that this is never without personal health risk. We prepared properly doing all kinds of risk assessments and pledging not to go for plants in unreachable places. But as soon as you are in the field, we seem to suffer from selective amnesia. On one of our hiking trips around Chicken, we spotted a rare poppy, Papaver alaskanum - which also occurs in Canada. The fact that the flower was growing on a steep cliff above a drop of about 200 meters onto the stony riverbed below didn’t seem to occur to us. Risking muddy trousers and a very painful death, we collected the beauty. Who says science is not for adrenaline junkies!
The difficulties we encountered on the field highlight the importance and value of herbarium specimens. In some cases, this type of material might be the only available source of data, as it is the case for Anne-Sophie. Broad distribution areas, scattered distribution, challenging topography, limited time and funding, climate change, etc. are many reasons why herbarium specimens are and will always be a major source of information. Therefore, we ended our trip in the Fairbanks Herbarium, which fulfilled all our hopes. We warmly thank Steffi Ickert-Bond for authorizing us to sample, and Carolyn Parker for her great help. We were able to sample all the targeted species, collected from various environments in Alaska but from Russia as well.
Last summer was a great opportunity for us to explore a new country and some of its various faces. But more importantly, it enabled us to explore other aspects of our job. First, attending an international conference taught us that communicating our research with credibility and eloquence is as important as the biological question and the results. Second, field work taught us that obtaining data doesn’t start with extracting DNA in the lab. It sometimes starts hundreds of km away, decades ago. Depending on your study group distribution, the risk of sampling failure can be very high. Therefore, it is important to maximize the use of the collections we already possess. On another hand, getting familiar with your study group in its natural environment is a priceless opportunity to understand it better and... to be even more excited about your studies! After a sampling trip in Alaska for Anne-Sophie, perhaps a sampling trip in South Africa for Yannick?!