Embryology 2024: a summer like no other Free

Each summer since 1893, a small group of scientists from around the world have convened at the Marine Biological Laboratory (MBL) in Woods Hole, Massachusetts, USA, to work on the most exciting model systems in developmental biology. At its surface, the Embryology Course is an advanced research training course with lecture- and laboratory-based training. But underneath, Embryology is a fearless embrace of the unknown, more hours in a day than seems possible, and a thriving scientific community. Here, we share our perspectives as students of the 2024 Embryology Course (organized by Drs Tatjana Piotrowski, Athula Wikramanayake and John Young), and the many facets that made this course unique and invaluable to us (Fig. 1).

Have you ever wondered how a sea star is born? When a frog first sees the light of day? How a butterfly grows wings to fly? The Embryology Course is an Evo-Devo Eden to study endless forms most beautiful and most wonderful. Over the course of 6 weeks, we explored everything from echinoderms to mammals, and gained an overview of the emerging questions and systems in developmental research.

The course is structured into several modules covering an array of model organisms. In 2024, these included echinoderms, ascidians, nematodes, tardigrades, planarians, acoels, arthropods, mollusks, zebrafish, frogs, chick, mouse, cephalopods, cnidarians, annelids and ctenophores. Each module was accompanied by a handbook containing key information about the module's organism(s) and how to work with them in the laboratory. These manuals were prepared by the faculty and often included classic experiments and techniques we could learn, as well as suggested projects to jumpstart our experiments.

Among the ‘classics’, we had the opportunity to perform Ethel Browne's transplants in Hydra (Browne, 1909) and replicate the Spemann–Mangold organizer experiment in Xenopus (Spemann and Mangold, 1924). In some modules, such as frogs and arthropods, we worked in groups on pre-proposed projects, which included live imaging to visualize bottle cell dynamics in Xenopus gastrulation or examining butterfly wing scale gene expression during development. In other modules, such as nematodes or Hydra, we were greeted by a veritable buffet of transgenic strains and reagents and were encouraged to let our creativity flow and design our own experiments. In either case, we had full autonomy to chase our interests (as a group or individually), and the faculty and teaching assistants (TAs) were always open to brainstorming novel experimental designs. Every idea was encouraged, and although many, many experiments failed, we lived up to the MBL's (unofficial) motto to ‘study nature, not books’.

In encouraging exploration and creativity, Embryology spared no expense. With access to cutting-edge microscopes and reagents, world-leading faculty and experts, and advanced data analysis software, we were afforded the freedom to explore (Fig. 2). At times, we were bold, risky, and downright outrageous – grafting two posterior ends of an acoel together, doing cross-species Spemann–Mangold organizer grafts, or propagating a sponge never before cultured in a lab (Fig. 2J). This resulted in beautiful discoveries, and some disasters. Nevertheless, even an unsuccessful experiment can produce a stunning or hilarious result, as seen at the bi-weekly ‘Show 'n’ Tell’ gatherings. Here, we were each given 3 minutes to present our science from the last 2 weeks (if presenting in a group, individual times were combined). Presentations ranged from serious to creative and highlighted how, even with access to the same reagents, there was no limit to the incredible diversity of approaches and interests. We celebrated the wins, cheered the losses, and pelted the speakers with foam balls once their time was up.

Near the end of the course, we debated what properties make ‘the ideal’ research organism for developmental biology. Needless to say, we needed empirical data, and so we conducted a survey (Fig. 3). Together, we agreed on five key categories: maintenance cost, ease of handling, embryo accessibility, availability of genetic manipulation tools, and interesting biological questions.

Perhaps unsurprisingly, echinoderms, frogs, zebrafish, fruit flies and Caenorhabditis elegans scored highest overall, reflecting their well-earned status as effective and widely used models in developmental biology. Conversely, emerging research organisms, such as cephalopods, ctenophores, ascidians and skates, ranked lowest overall, yet ranked highly in ‘interesting biological questions’. This indicates that, despite their potential to address many amazing biological questions, such systems are profoundly limited by technical challenges. Notably, upon further examination, we observed a high variance of perceptions in what constitutes ‘interesting biology’. From this, we conclude that there is no single ideal research organism. Instead, it is important to choose a research organism that fits well with one's own research question. Granted, this is a brief survey with a somewhat biased cohort. However, even the limited results of this survey support the importance of investing in the development of non-traditional research organisms and the potential benefits for the scientific community at large. After all, there are countless biological questions that await discovery and there is no perfect model system.

The Embryology Course has a reputation for being intense, with good reason: for 6 weeks, our days were packed with lectures, lab, meals, beach, softball and very little sleep (Box 1). Mornings at the MBL began with a rush to eat breakfast at Swope or grab a cuppa from Coffee O, before settling in the lecture hall at 09:00 sharp. We began with two lectures by the module's faculty, providing an overview of the research organism(s) and the current state of the field, and their own work. After a short trot between buildings and a top-up of caffeine, we reconvened in the infamous ‘Sweat Box’ – a small, glassy conference room that does, in fact, get quite warm with so many people crammed inside. Here, we had the opportunity to ask the lecturers anything. Topics ranged from technical scientific questions to philosophical applications of research, as well as more personal questions, such as the challenges faculty faced when first starting their labs or how to approach mental health issues in academia. Discussions were always lively, informative, and much too short. After lunch or a swim at Stony Beach, we gathered in the laboratory for the day's experiments. At the beginning of each module, we received a hands-on orientation. Faculty and TAs demonstrated animal handling and essential techniques, then cut us loose. By late afternoon, we had self-organized into teams or decided to go solo, ransacked the freezers for reagents, and booked all the microscopes for the week.

After dinner at Swope and another swim (or a few swings at a softball), we returned to our experiments. Evenings in the lab were electric – the room was abuzz with the excitement of working with a new critter or trying a high-risk experiment, never mind that it was already pitch-black outside. And this energy was contagious: faculty and TAs often stayed in the lab into the small hours to help set up experiments, kept awake by an impressive cocktail of professionalism and our novice excitement. It was not unusual to still find students and faculty peering into microscopes long after midnight, or in the break room playing games or sharing beers to pass the time between incubations. Experiments complete, we left for our beds or the beach, ready to start it all over again the next morning. It's exhausting; it's exhilarating; it's Embryology.

The time outside the lab or lecture hall was just as memorable as the science itself. If not catching up on much-needed sleep, we were making the most of our beautiful surroundings in and around Woods Hole. A favorite activity was softball, which quickly became the unofficial centerpiece of the course. For many of us, especially non-US participants, learning the rules and tactics was a challenge, considering few of us had ever held a bat before. However, what started as a group of rookies fumbling their way through practice turned into a cohesive team by the end of the course. Although we narrowly lost the annual softball derby against the Physiology students, playing softball was undoubtedly a highlight of the course and helped us become a great team, both on and off the pitch.

We also spent plenty of time at the beach, either for a quick lunchtime swim or a nocturnal foray to admire the bioluminescent dinoflagellates that lit up the water. Indeed, the interest in biology didn't stop at the laboratory door. In the sea squirt, tardigrade, nematode and ascidian modules, many of us ventured out to collect our own samples. Birdwatching was a popular activity, with the highlight undoubtedly being the sighting of a black skimmer on Martha's Vineyard. Whale-watching was also a memorable excursion, where we were lucky enough to observe several whales performing spectacular maneuvers: flipper slaps, body rolls and stunning dives showcasing their huge flukes. We also toured the MBL Marine Resources Center and saw the many animals maintained for research, including skates, dogfish, horseshoe crabs, and squid. A trip on the MBL's sampling vessel, the Gemma, also provided some temporary lab pets, including a giant hermit crab we named Jimmy.

Smaller activities (perfect for passing time during incubations) included games such as Bananagrams or improvised chair races. Evenings were best concluded with a drink in the break room or by blasting some karaoke hits in the Sweat Box. Here, the international spirit of the course became evident, with Italian, French and German songs echoing through the institute's halls alongside popular English hits. Embryology epitomizes the mantra ‘work hard, play hard', and in these moments of play we were able to form the life-long interpersonal relationships for which the course is renowned.

Whether you are looking for a new model system, to learn a new skill, or simply to take a step back from your own research, Embryology offers the unique opportunity to reignite your passion for discovery at any stage in your scientific career. The 2024 cohort included PhD students, post-doctoral researchers, junior faculty, and two visiting undergraduates. We all enrolled for different reasons and with various levels of experience, but in the Embryology Course, we were all students.

As a junior graduate student, the course is uninhibited exploration that builds confidence and independence. You will look at your project with fresh eyes after the MBL. As a senior graduate student, the course can broaden your knowledge of the field and provide important context for your work. For those doubting whether they would like to stay in academia or move into a different sector, such as industry, taking the course can help you make those difficult decisions. Regardless, you will connect with many new and established researchers, which is an invaluable resource for advice and future collaborations.

The course was also extremely useful for those of us in postdoctoral or junior faculty positions. Starting a career as an independent researcher can feel like an obstacle course where, in many cases, you feel alone and disoriented. Where should I start? Which idea will really be mine? Which model will be best suited to answering my new questions? Who can I collaborate with? How do I distinguish my work from that of my supervisors and existing collaborators? This course can be leveraged to explore new areas of research and inspire future endeavors, while building a strong international network of colleagues and collaborators.

Two undergraduates from the Society for Developmental Biology's Choose Development! program each joined the course for 1 week of their choosing. The knowledge and networks built into the course helped inform their career choices after graduation.

Attending the Embryology Course was transformative in ways we had not anticipated. As promised, the course lectures connected the practical experience to larger themes in developmental biology and allowed us to paint a complete picture of research in the field and better understand current frontiers. The laboratory training indeed provided a strong foundation in embryo handling, toolmaking, precise micromanipulation, microinjections and advanced imaging skills. But more than that, the course broke our routine and built versatility – pushing us to venture out at night to collect samples, rush to look at an unknown embryo under the microscope, and think outside of the box. We were given not only the knowledge and tools to explore different aspects of developmental biology but also the space to experience the joys of doing curiosity-driven science. The Embryology Course was a reminder to embrace curiosity and experience failure as an essential part of the scientific journey. It is said that every child is a scientist, and it truly felt like we were all children again at the MBL.

But perhaps the course's most renowned asset is its community. The Embryology Course serves as the scaffolding for a vast scientific network, which includes not only alumni and vendor contacts, but also the countless dedicated faculty and TAs who make the course possible. Curious about our research, suggesting experiments, new lines of research and collaborations, they gave each of us the legitimacy to be a researcher and build the spirit of an open scientific community. This dynamic enabled us to form a strong group cohesion, both scientifically and personally, making our own classmates the most reliable future collaborators. Regardless of career stage, this was an invaluable opportunity to explore science with amazing people and form meaningful, lasting connections.

Returning to our labs, we carried not only newly learned technical skills but also a renewed determination to foster this spirit of exploration and collaboration in our own research environments. With newfound confidence, we felt inspired to try new techniques, venture into new fields, and work with different model organisms.

Six weeks of Embryology in Woods Hole was a life-changing experience, just as it presumably has been for the 129 generations of students who came before us. Each of us left with a renewed enthusiasm for science and developmental biology, and a network of life-long friendships. We would recommend the Embryology Course to any embryologist, at any stage of development.

We thank the course assistants, Erica Lin, Paul Maier and Stanley Marjenberg, without whose invaluable and tireless dedication this course would not be possible. We also thank Lisa Cameron, Michelle Itano and Paula Montero Llopis for their expertise and imaging instruction, as well as Bruker, Hamamatsu, Hewlett Packard, Leica, LifeCanvas, Nikon, Oxford Instruments Andor, Vortran, Yokogawa and Zeiss for their generous donations of microscopes, software and workstations to the course. Thank you to the Huisken lab for providing us with a custom-built light-sheet microscope. Thank you also to Adair Oesterle and Sutter Instruments for their donation and instruction of injection equipment. We thank the almost 100 course faculty members and TAs for their enthusiasm, mentorship and commitment to teaching, as well as the MBL staff who provided us with teaching space, accommodation and catering. We thank the course organizers, Tatjana Piotrowski, Athula Wikramanayake and John Young, for their tireless organizational and logistical support, and for putting together a truly amazing course. And, lastly, we thank our classmates for the stimulating science, fond memories and an unforgettable summer.