2023 in invertebrates

Boisduval’s blue butterfly on a weedy geranium, on Santa Cruz Island. (jby)

As a final taxonomic catch-all for my 2023 nature photography, let’s go with … invertebrates? If I’m not taking a photo of a plant, a bird, or a mammal, it’s most likely an insect visiting a flower. I do love a good plant-pollinator interaction. And while larger animals are a challenge to manage well with my 150mm lens, I can frequently catch some nice close images of butterflies nectaring, like the blue above, or the Clodius parnassian below.

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The biology behind a superb superbloom, in the Los Angeles Times

California poppies, fiddlenecks, lupines, and other wildflowers at the California Poppy Preserve back in early April. (jby)

Yesterday’s Los Angeles Times has an article that goes into some of the biology behind this spring’s “superbloom” in California — plants all over the state responding to an exceptionally cool, wet spring with profuse flowering. Corinne Purtill, the author, called up some rando to enthuse about all that spring greenery:

Those 31 atmospheric rivers delivered steady, nourishing rainfall from October to March. Regional temperatures remained moderate as well, without any sudden early-spring heat waves to kill off fragile baby plants.

The combination of those two factors has produced “an absolutely glorious spring,” one that has been more vibrantly colorful for longer than any in recent memory, said Jeremy Yoder, a Cal State Northridge biologist.

As the headline says, everything is blooming everywhere all at once, and it reflects how the life histories of plants in many California natural communities are adapted to periodic drought. Check out the whole piece for more from me and my fellow plant nerds on the science behind a spring bloom that has us all agog.

New paper: Conservation challenges and solutions for the Mojave Desert

Burned Joshua trees at the site of the 2020 Cima Dome fire in Mojave National Preserve (Flickr, jby)

A big review article, written with Joshua Tree Genome Project co-PI Chris Smith and a bunch of other Joshua tree experts, went online today at Biological Conservation. In it, we attempt to comprehensively describe the challenges to biodiversity conservation in the Mojave Desert, and outline solutions — more detail over on the lab blog, or check out the paper itself via this sharing link, which provides free full-text access through January 20, 2023.

New publication: A genetic fingerprint of coevolutionary diversification

A red milkweed beetle, Tetraopes tertophthalmus, on its host plant (jby)

A new paper from the lab — coauthored with all three of the Yoder Lab’s graduate student alumni — is now online ahead of print in the journal Evolution Letters. In it, we analyze population genetic data from 20 pairs of plants and herbivores, parasites, and mutualists that live intimately on those plants to test for evidence that the associate species’ population genetic structure aligns with that of their host plants. This is an expected result if adaptation to the host plant drives diversification of the associates — and we found that it is indeed a recurring pattern. This is a pretty neat result, and, I think, a nice contribution to a long-established literature on how intimate associations with plants has driven the diversification of groups like butterflies and beetles.

The variety of queer scientists in The Queer Variable

Shaun O’Boyle and Alfredo Carpineti have spent the last two years interviewing LGBTQ+ folks working in the sciences, and the result is now available today on the website of Pride in STEM: an e-book compilation of 40 edited interviews, The Queer Variable. I’m very glad to have been included, as just one voice in an impressively international (if necessarily Anglophone) chorus. The book is something of an oral history, not of a single event or project, but of the career trajectories of the interviewees and how their queer identities have intersected and shaped their work — a topic addressed in a more systematic (dry) manner in the second Queer in STEM paper [PDF]:

Three key processes emerged from our analysis of participant experiences and provide an explanatory framework for how queer STEM workplace identities are shaped by a combination of internal and external influences (see Figure 1). Defining explains how these individuals come to understand and name themselves as queer in terms of gender and/or sexuality; Forming refers to their construction of specific STEM identities; and Navigating describes how the interplay of professional and personal influences impacts expression of identity in places of work and study.

The Queer Variable effectively samples the wide range of ways LGBTQ folks have defined their queer identities, formed their place in a STEM field, and navigated the challenges of a career that incorporates both. Go download the free e-book and have a look.

On making the local news

This is a bit of a rehash from the social media platform whose name I will not utter here, but earlier this month I made my first TV appearance as an “expert” on Joshua trees, talking about the Joshua Tree Genome Project common garden experiments as a first step towards assisted gene flow to help the trees cope with climate change. It was a weird experience! The reporter emailed to arrange things and I agreed to an interview on Zoom, but I didn’t fully realize I was being recorded for broadcast until we were wrapping up. Mercifully, he selected the most coherent bits of what I told him and I didn’t make too many weird faces.

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New paper: How flowers’ symmetry may affect pollinator diversity

I’m delighted to announce a new paper published today in the Biology Letters, coauthored with Colin Carlson at Georgetown University and a CSUN undergrad researcher, Gio Gomez. In it, we examine a big collection of floral visitation records and find a pattern that pollination biologists have talked about but never quite directly demonstrated: the symmetry of flowers seems to shape the diversity of animals that visit them, and potentially provide pollination services. Here’s a brief “lay summary” we wrote to accompany the article:

For centuries, botanists have understood that the symmetry of flowers — whether or not they are “zygomorphic”, with a single line of symmetry — shapes how they attract and interact with pollinators. We examined 53,609 records of animal visits to flowers in 159 communities around the world, and found that zygomorphic flowers are visited by fewer potential pollinator species. This may explain broad patterns in the diversity of flowering plants, in which zygomorphic flowers are associated with faster formation of new species. It also suggests that plant species with zygomorphic flowers may be at greater risk of extinction due to pollinator loss.

We released this work as a preprint on bioRxiv awhile ago, but you can now find the final “official” version of the peer-reviewed paper on the Biology Letters website.

This is an exciting paper because it’s my first foray into pollination ecology proper, and because of its place in that broader field of research — and also because it’s the first paper I’ve published with a student coauthor since starting on faculty at CSUN. On top of all that, the project has been a really nice bridge between my interests (mutualism) and Colin’s (host-associate community ecology), and it’s kicked off a collaboration that has produced some even more exciting results, coming soon to a preprint server near you.

New paper: Meta-analysis of local adaptation experiments compares sources of natural selection

Low clouds surround mountaintops in the San Gabriel Mountains. The analysis in the new paper suggests that selection by abiotic factors like high-elevation conditions may often be weaker than selection created by interactions between species. (Flickr: Jeremy Yoder)

Local adaptation, in which populations of a species become better able to survive and thrive in their home environment than in conditions found elsewhere in the species’ range, is a widespread pattern that evolutionary biologists have long used to study the causes and consequences of natural selection. My newest paper, which is now online ahead of print in The American Naturalist, combines data across many studies of local adaptation to answer a persistent question about the history of life on Earth — has evolution been influenced more by selection arising from environmental conditions, or by interactions among living things?

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2018 photos: Fieldwork (and tourism) in Spain and France

2018.06.20 - Gruissan
Gruissan, a coastal village near Narbonne.

If I’m really going to take my digital life off Facebook, I have to get serious about tending to a more distributed version of that site’s functions. Exhibit A is my Flickr account, which I’ve gotten lax with updating — I was almost a year behind with uploading images there! The holidays have been a good chance to catch up, though, and I’ve finished updating through a trip to Spain and France for fieldwork last June.

I was there to take samples of Medicago truncatula along the Spanish and French Mediterranean coasts — ridiculously pretty territory, even when a snafu with my car rental meant I had to do a fair bit of collecting by mass transit and rental bike. I flew into Madrid (with a layover in London), then to the Spanish coastal town of Málaga; then I spent most of a week in and around Narbonne, France, and finished with a day in Paris before flying home (again via London). It was my first time in both Spain and France, and my first time in Europe in more than a decade.

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New paper: Conflict and communication in mutualism

Medicago truncatula, or barrel clover, a member of the legume family that hosts bacteria in its roots. The bacteria transform nitrogen gas from the atmosphere into fertilizer for their host plant, and the host feeds the bacteria with sugar. Experiments with barrel clover and its mutualists have shown that signals between the plant and the bacteria are important in this interaction, and provide an inspiration for the evolutionary models built by Yoder and Tiffin. (Flickr: jby)

I’m very excited to see this in virtual print — it’s a new model of coevolution between mutualists that takes into account signals between the partners as well as the benefits they provide each other (or don’t).

Yoder JB and P Tiffin. 2017. Sanctions, partner recognition, and variation in mutualism. American Naturalist doi: 10.1086/693472.

I’ll try to write about this in more depth at some point, but here’s the lay summary at the American Naturalist website:

Mutually beneficial relationships between species, or mutualisms, are ubiquitous in the living world, with examples ranging from flowering plants that rely on animal pollinators to fish that clean the teeth and scales of other fish. Mutualisms are often imperfect — one partner or the other varies in the quality of the help it provides. Evolutionary theory predicts that this should break up the relationship, but most mutualisms hold together in spite of partners that take the benefits of mutualism without properly paying them back.

This paradox may be explained by the fact that there’s more to mutualism than trading goods or services. This is a key result of mathematical evolutionary models published in the American Naturalist by Jeremy Yoder and Peter Tiffin, biologists at the University of British Columbia and the University of Minnesota. Yoder and Tiffin built a mathematical evolutionary model of mutualists that communicate before trading resources, and compared it to simpler models with only resource-trading or only communication. In the model with communication and resource-trading, host could “sanction” by cutting off resources to prevent poor quality partners from taking over, but evolution of the signals sent by partners and the hosts’ response to those signals maintained variation over time. Neither of the simpler models could do this. With only resource-trading, sanctions eliminated all poor-quality partners, and all variation; with only communication, poor-quality partners took over the mutualism.