Sunday, August 5, 2018

Botanists at Work--Botany2018 Meeting

This year I again attended the Botanical Society of America annual meeting this year in Rochester, Minnesota. I go to keep up--since I write this blog from retirement, attending professional meetings helps me check that I am providing accurate information.

Rochester Minnesota

So I attended general lectures and technical papers, read posters, looked at the books the publishers brought and, of course, talked to people.

spring wildflower of eastern North American forests
I caught a number of talks where the authors had found ways to ask: "has the climate changed right here and are the plants (and animals) responding?" For example, Mohonk Preserve (link) near NewPaltz, New York has a climate record (rainfall, temperature) going back to the 1880s. Due to naturalist owners who wrote down their observations, they have notes of first flowers, first migratory birds and much more, going back to nearly 1900. The result is they can show that the average temperature has risen 2 degrees in 100 years and that some wildflowers are flowering more than a week earlier while others have not changed their flowering time. World weather is complicated and the models do not predict uniform change, so obsevations from diverse places are needed to really know what is happening.
a beardtongue, genus Penstemon
271 species, their relationships slowly untangling
Analysis of plant relationships with DNA continues to check and sometimes correct plant classifications. The classification system is supposed to show relationships--members of the same species should be more closely related than members of the same genus, which are more closely related than members of the same family. So DNA testing, just like in humans, is discovering unknown relatives. This has gone from studies of a few plant species from one region to comparing virtually all the species in genera with over 250 species, for example Penstemon (link). International collaborations let studies of widespread plants like chickweeds (Stellaria) include species from around the world. Of course international politics impedes this work. Botanists will go to very dangerous places in search of specimens, but wars and inter-country hostility remain major impediments to getting complete information.
chickweed, Stellaria
chickweed, Stellaria (carnation family, Caryophyllaceae)
with native species in China, Chile and Colorado...and many others
Computing power and time-saving solutions have grown dramatically, so that DNA information from all those plants can be analyzed in a reasonable period of time. It has always been possible for biologists to ask questions so grand that to answer them would require big computers five years to analyse, which, practically speaking, makes those questions impossible to answer. But better computers and clever approaches allow ever more powerful analyses. Particularly intriguing to me are analyses that include geography: did the plant's ancestors jump between watersheds in the US Southeast (very short distances as the crow flies), or did they spread almost entirely up and down river (since plants are not birds)? Comparing the DNA in the plant populations can answer that. (For Trillium lancifolium, the plants generally stayed in the same drainage but there were exceptional cases.)

Impressed by the studies I saw, I suggested to a group of systematists, the people who do this kind of work, that we were getting near to understanding many North American plant groups. They shook their heads at my simplicity. "Oh no. Most of them will need to be reconsidered." Really? Upon reflection, I realized that studies done 10 years ago comparing only one modest DNA sequence between 15 (of 200) species are so incomplete that they really should be redone with current methods, using 3 or more quite different DNA sequences (rapidly changing, slowly changing, maternally-inherited) in virtually all 200 species. That is both discouraging and encouraging. Perhaps much of what we think we know is inaccurate, done with flawed methods. The good news is, there are still lots of interesting things to discover, some likely hiding in plain sight.
bergamot, Monad
bergamot, Monarda, North American mint
Also galloping forward is our understanding of the genes underlying the traits that distinguish one plant from another. Here, link from the Mint Genomics Resource website, is a biochemical pathway in peppermint. The compound in the box, geranyl diphosphate, can be converted into any of the three compounds: 1,8 cineole, alpha-terpeneol, or limonene. The particular scent and taste of peppermint comes from its genes creating a particular combination of these molecules. Peppermint's relatives spearmint and bergamot smell and taste differently because the same pathway makes the compounds in different amounts. The details are complicated and there is lots we do not yet know but I really enjoy checking in for updates, watching our understanding improve.
Minnesota stream
Minnesota forest scene
A beloved tradition of Botanical Society meetings is a talk about the plant geography of the area. Minnesota is the meeting place of three major ecosystems: grasslands, deciduous forest and coniferous forests. George Weiblen provided an entertaining overview of Minnesota geology and botany -- it is clearly a place I should explore more thoroughly.

I left full of ideas, with papers to look up and read, websites to check out, personal projects to consider...for a plant geek, a great time.
plant geek button
 I even got the button.

Comments and corrections welcome.

Citizen Science - Progress in science need not be left to people who do it full time. Many of the things we want to know need lots of observations that can be contributed on a part time basis, like the invaluable observations of the owners of what is now Mohonk Preserve
Here are some lists of projects:
National Geographic link 
Zooinverse link
The Nature Conservancy link 
NEON link

A few websites based on collaborative studies of plants
Mint genome project, Lamiaceae  link
Tomato family studies Solanaceae link
Grasses, Poaceae link
Melastomataceae page link
Morning glories and bindweeds Convolvulaceae link

Papers from the meeting
Dedanna, R., G. Barboza and S.D. Smith. Tracing the evolution of the inflated calyx syndrome in the Physaloids (Solanaceae)
Feldsine, N. Potential phenological shifts of first bloom dates in southern New York: using long-term phenology data to understand local effects of climate change
Kramer, E., Y. Min, M. Edwards, C. Meaders, E. Ballerini and S Hodges. Exporing the genetic basis of floral novelty in Aquilegia
Lamprey, J. Role of river watersheds on diversification and endemism in native plant species: A phylogeographic study of Trillium lancifolium (Melanthiaceae)
Pusey, J. and many coauthors. Long-term (100 year) trends in monarch butterfly and milkwee (Asclepias) abundance estimated from natural history collections
Ragsac, A., P. Fabre, T. Sarkinen, R.Olmstead. Phylogeny of Tecomeae (Bignoniaceae): a global tribe of Neotropical origin.
Sharples, M. Inferring the biogeographical history of the cosmopolitan Angiosperm genus Stellaria L.
Struwe, L., R. Setubal, C. Frasier and J. Molina. Toxic Story: Phylogeny and classification of Stychnos (Loganiaceae)
White, D. and R. Mason-Garner. Phylogeographic analysis of the domestication of coca (Erthroxylum spp.)
Xiang, C., G. Hu, B. Drew, A. Takano, D. Soltis, P. Soltis and H. Peng. Molecular phylogeny and taxonomy of East Asiatic Salvia (Lamiaceae, Nepetoideae)
Papers at meetings are expected to be new work, not previously published, so you won't find these online yet. But generally the research groups have web pages where you can get more information.

Kathy Keeler, A Wandering Botanist

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