We are overjoyed to announce that NSF is funding a new and collaborative research project to look at the genomic underpinning of local adaptation in the Atlantic silverside! Check out below for a first glimpse of the project website.
NSF-OCE #1756751 The genomic underpinnings of local adaptation despite gene flow along a coastal environmental cline (2018-2021)
Oceans are large, open habitats, where it was previously believed that the lack of obvious barriers to dispersal would result in extensive mixing, thereby preventing organisms from adapting genetically to particular habitats. It has recently become clear, however, that many marine species are subdivided into multiple populations that have evolved to thrive best under contrasting local environmental conditions. Nevertheless, we still know very little about the genomic mechanisms that enable divergent adaptations in the face of ongoing intermixing.
This project focuses on the Atlantic silverside (Menidia menidia), a small estuarine fish that exhibits a remarkable degree of local adaptation in growth rates and a suite of other traits tightly associated with a climatic gradient across latitudes. Decades of prior lab and field studies have made M. menidia one of the marine species for which we have the best understanding of evolutionary tradeoffs among traits and drivers of selection causing adaptive divergence. Yet, the underlying genomic basis is so far completely unknown.We will integrate whole genome sequencing data from wild fish sampled across the distribution range with breeding experiments in the laboratory to decipher these genomic underpinnings. This will provide one of the most comprehensive assessments of the genomic basis for local adaptation in the oceans to date, thereby generating insights that are urgently needed for better predictions about how species can respond to rapid environmental change. The project will provide interdisciplinary training for a postdoc as well as two graduate and several undergraduate students from underrepresented minorities. The findings will also be leveraged to develop engaging teaching and outreach materials (e.g. a video documentary and popular science articles) to promote a better understanding of ecology, evolution, and local adaptation among science students and the general public.
The project is organized into four interconnected components
Part 1 examines fine-scale spatial patterns of genomic differentiation along the cline to a) characterize the connectivity landscape, b) identify genomic regions under divergent selection, and c) deduce potential drivers and targets of selection by examining how allele frequencies vary in relation to environmental factors and biogeographic features.
Part 3 integrates patterns of variation in the wild (part 1) and the mapping of traits under controlled conditions (part 2) to a) examine how genomic architectures underlying local adaptation vary across gene flow regimes and b) elucidating the potential role of chromosomal rearrangements and other tight linkage among adaptive alleles in facilitating adaptation.
Part 4 examines dispersal – selection dynamics over seasonal time scales to a) infer how selection against migrants and their offspring maintains local adaptation despite homogenizing connectivity and b) validate candidate loci for local adaptation.
Members of the Baumann lab attended two back-to-back meetings in Portland, OR, in February. From 11-16 February, we participated in 2018 Ocean Sciences Meeting, while from 17-19 February we all took part in the 4th Ocean Acidification Principal Investigators meeting.
Holding the fort at the Rankin lab were Julie and Charles, who did an excellent job. Thank you guys!
At OSM, Hannes chaired a large session (OC51, OC52) titled “Multiple Stressors and Multiple Disciplines: Understanding the Consequences of Global Ocean Change for Marine Species” together with colleagues from Bermuda Institute of Ocean Sciences (BIOS, Amy Maas), the Virgina Institute of Marine Sciences (VIMS, Emily Rivest), and the University of South Carolina (Catherine Davis). The line-up of speakers was impressive and included our very own Emma Cross (speaking on brachiopod resistance to CO2) and Hans Dam (presenting our findings of multigenerational CO2 effects on the copepod Acartia tonsa).
Portland, albeit rainy, was as usual a great city to come to.
OSM2018 sessions OC51, OC52 (Baumann, Maas, Rivest, Davis) Multiple Stressors and Multiple Disciplines: Understanding the Consequences of Global Ocean Change for Marine Species
Zimmerman et al. Modeling the Impacts of Water Quality and Climate Change on Submerged Aquatic Vegetation in the Chesapeake Bay
Frieder et al. Advancements in Quantifying Energy Costs for Organisms to Respond to Ocean Change
Hofmann et al. Who’s Your Mommy? Transgenerational Effects in Purple Sea Urchins from Nearshore Kelp Forests in California
Waldbusser et al. Understanding the multi-stressor impacts of ocean acidification on marine calcifiers: What controls biocalcification? Saturation state or substrate inhibitor ratio
Silbiger et al. Nutrient addition disrupts dependence of calcification on aragonite saturation state
Cross et al. A 120-year record of resilience to environmental change in brachiopods
Dam et al. The copepod Acartia tonsa in a greenhouse world: Transgenerational plasticity of life history traits
McLaskey et al. Ocean Acidification Driven Changes to Food Quality are Transferred Unpredictably Across Trophic Levels
Palmer et al. Recent Fossil Record Provides Unique Insight into Impacts of Multiple Stressors on Community Ecology
Krumhardt et al. Coccolithophore growth and calcification under future oceanic conditions
Rivest et al. Multiple stressors elicit unique responses in animal and algal partners: the potential for physiological plasticity in symbiotic coral larvae under global ocean change
Cornwall et al. Impacts of pH Variability and Past pH History on Coral and Coralline Algal Calcification: a Mechanistic and Multi-generational Approach
Eagle et al. Combining microelectrode and geochemical approaches to study the impact of pCO2 and temperature changes on the internal pH and carbonate chemistry of corals and their relation to growth responses
Weinnig et al. Physiological Response of a Cold-Water Coral (Lophelia pertusa) to the Combined Stressors of Climate Change and Hydrocarbon Influence
Bednarsek et al. Interactive effects of temperature and acidification on pteropod distributions in the California Current Large Marine Ecosystem
Davis et al. Juvenile Rockfish Recruits Show Resilience to CO2-Acidification and Hypoxia across Biological Scales
This research feature makes the case for multistressor research to a broad general audience and introduces our NSF project and its participants. Download the feature by clicking on the pictures or the link below.
On this dimly lit November afternoon, rain mercilessly drenched scientists and crew on board the R/V Auk as it slowly navigated the waters of Stellwagen Bank. A world like a wet sponge. Sky and ocean, indistinguishable.
Thanksgiving, the next day.
Despite the circumstances, the team’s mood was nothing short of elated. Our small beam trawl had just spilled hundreds of silvery fish on deck, wriggling like eels. They were Northern sand lance (Ammodytes dubius).
Running ripe adults.
Apparently, they like Thanksgiving, too.
As the ship docked back in the Scituate, Mass., harbor that day, the rain thinned to hazy darkness.
“Let’s get a coffee and then on the road,” mumbled Chris, who led the team, “the real work of the experiments has just begun.”
Stellwagen Bank, the National Marine Sanctuary just north of Cape Cod, is a true hotspot for some of the Atlantic Ocean’s most iconic creatures: whales, seals, tuna and seabirds, who all share a particular appetite for this one fish – sand lance. Some experts in the sanctuary’s ecosystem call this species its “backbone.” Others consider it a classic forage fish, responsible for transferring massive amounts of energy from lower to upper levels on the food chain.
Sand lance have a few interesting and rare characteristics. They alternate between schooling and foraging in the upper water column and extended periods of being almost completely buried in sand. For that, they rely on sand of a particular grain size and with very little organic content. It’s the kind of sand that defines large areas of the Stellwagen Bank.
Surprisingly little is known about the ecology and ecosystem importance of this sand lance species, although research on its European relatives (A. tobianus, A. marinus) is more advanced. In particular, experiments on early life stages of Northern sand lance have been lacking, save for some pioneering work on rearing methods of the related A. americanus (Smigielski et al. 1984). One question that was of particular interest to our lab involved the potential sensitivity of this fish species to carbon dioxide (CO2). That’s due to two other interesting and rare characteristics of sand lance. They spawn in late fall and winter in cold (and still cooling) waters, which is why their eggs and larvae develop extremely slow compared to other, more typical spring and summer spawning species. In addition, the species is found not in nearshore, but offshore coastal waters, where smaller seasonal and daily CO2 fluctuations more closely resemble oceanic conditions. Could sand lance offspring be particularly sensitive to higher levels of oceanic carbon dioxide predicted during the next 100 to 300 years as climate change effects intensify?
Over the past two years (2016-17), we successfully found and sampled spawning ripe sand lance on Stellwagen Bank during a narrow window in late November. Eggs and sperm from adults were removed on board or after being transported live to our laboratory at UConn Avery Point. We reared newly fertilized embryos to hatch and to the feeding larval stage, under different sets of temperature and CO2 conditions, measuring survival and growth traits along the way.
Our experiments are still ongoing, and rearing protocols are being improved.
The preliminary findings, however, are stunning. Survival to hatch was dramatically reduced under elevated and high compared to baseline CO2 conditions. It was severely lowered at higher (10°C or 50°F) compared to lower temperatures (5°C or 41°F). Our second experiment this year appears to repeat this pattern. If these results continue, that would mean sand lance is one of the most CO2-sensitive species studied to date.
General interest in sand lance goes beyond its sensitivity to carbon dioxide. Given the species importance for the ecosystem and coastal economy, there are now increasing efforts to better understand sand lance feeding ecology, distribution and relationship to the rest of the food web. In this regard, funding of our project by the Northeast Sea Grant Consortium proved prescient and a seed for subsequent grants from MIT Sea Grant and the Bureau of Energy Management (BOEM) to continue the work. Surely, the groundswell of interest in sand lance is commensurate with its importance and will enable insights into better management strategies for sensitive ecosystems like those along the U.S. Atlantic coast.
Collaborators on this project are:D. Wiley of the National Oceanic and Atmospheric Administration-Stellwagen Bank National Marine Sanctuary; P. Valentine of the U.S. Geological Survey; and S. Gallagher and J. Llopiz, both of the Woods Hole Oceanographic Institution.
17 January 2018. Since November 2017, we have ongoing experiments with offspring of Northern sand lance (Ammodytes dubius), a winter-spawning forage fish of ecological importance along the North-American Atlantic coast. The clip below shows larvae almost two months after fertilization, developing nicely in 5C water and feeding actively on live rotifers. The experiments, led by Chris Murray for his PhD research, study the CO2 sensitivity of this species in our factorial larval rearing system. To our knowledge, this is the first time that this particular species has been reared that far under experimental conditions. Have a look!
15 December 2017. The whole Baumann lab joins in congratulating Jake on his successful graduation with his Master’s degree from UConn! Jake embodied the spirit of a great student and team member, one who did not only seek to get something from the place he spent two years of his life but also one who left a great deal for us to remember. A wizard behind the camera, Jake has continuously enriched our lab with pictures that truly stand out and for which we will always be grateful. Jake helped in every aspect of the lab, but was particularly active in maintaing our monitoring efforts in Mumford Cove. For that, too, we are very grateful.
For his Master’s thesis, Jake painstakingly took it upon himself to retrieve and digitize the 40+ year time series of environmental observations from Project Oceanology, an ocean literacy organization that has been taking middle and high school students out to sea for decades. For the first time, his work allowed a quantitative evaluation of these data and a glimpse into the decadal changes in abiotic and biotic conditions in nearshore waters of Eastern Long Island Sound.
During his time at the Baumann lab, Jake also conducted an experiment on potential maternal effects and their influence on offspring CO2 sensitivity, which was recently published in the Journal of Experimental Marine Biology and Ecology
Snyder, J.T.*, Murray, C.S.*, and Baumann, H. (2018)
28 November 2017. The Journal of Experimental Marine Biology and Ecology just published the latest study by our group looking at differences in the CO2 sensitivity of Atlantic silverside offspring stemming from different mothers. Congratulations to Jacob Snyder for his first peer-reviewed publication.
Among the highlights of the study:
Offspring produced by different females varied in their sensitivity to high CO2 conditions.
Specific fatty acids in eggs were correlated to the log-transformed CO2 response ratio of embryo survival and hatch length.
Maternal provisioning might be an additional determinant of CO2 sensitivity in fish early life stages.
On 5-9 November 2017, the Baumann lab attended the 24th Biennial Conference of the Coastal and Estuarine Research Foundation (CERF) in Providence, RI. The conference is a unique blend of academic and conservation science and comprises an ideal venue for students to present their thesis research to a broad national and international audience. Best of all this year: the conference logo featured a beautiful piece of art depicting an underwater scene with our most beloved, famous fish, the Atlantic silverside. Big shout out to Ashley van Etten and her inspiring artwork!
Together with Steve Litvin (Monterey Bay Aquarium) Hannes convened a theme session titled “Physiological ecology in the Anthropocene: linking the laboratory and field” and talked about our recently published paper on pH and oxygen fluctuations in nearshore coastal environments. Jake presented his Master thesis research on the newly digitized long-term time series of Project Oceanology, and Julie talked about the first aspect of her ongoing research on silverside otoliths and inferred patterns of growth and temperature-dependent sex determination. Well done, all!
Baumann H. and Smith, E.M. 2017. Quantifying the covariance of pH and oxygen conditions across the diversity of US nearshore habitats.
Pringle, J.W. and Baumann H. 2017. Sex-specific growth and mortality patterns in juvenile Atlantic silversides (Menidia menidia) from Connecticut waters.
DeMayo, J.A., Park, G., Norton, L., Huffman, W., Finiguerra, M., Baumann H., and Dam, H.G. 2017. Combined effects of warming and acidification on life-history traits of the calanoid copepod Acartia tonsa.
Snyder, J.T. and Baumann H. 2017. A newly digitized 45-year dataset of environmental and biological observations from Long Island Sound.
15 October 2017: All members of the Baumann lab – Hannes, Emma, Chris, Julie and Jake had fun at an Open House event at the Avery Point Campus as part of the 50th Anniversary celebrations. The whole department participated with a flurry of educational activities and fun exhibitions.
Our lab manned a table outside the Rankin Lab, telling people about the nearshore fish community, the phenomenon of ocean acidification and the measurement of pH in water. Everybody chipped in, thanks!
Hannes also premiered reciting Dr. Seuss’ “The Lorax” in front of young and old in the AP auditorium.
Check out some of the fun around the “Ocean Acidification and our fish” table:
10 October 2017. Today, Chris, Emma, and Julie measured over 400 juvenile Atlantic silversides for their length and weight. This time, however, we did not euthanize the fish before, but successfully measured them while still alive, only a little drowsy from the mild anesthetic we administered before.
Click on the video below to have a look for yourself.
Congratulations all, for a job well done!