Maxwell Shafer

Maxwell Shafer

@maxshafer.bsky.social

Assistant Professor UofT Cell & Systems Biology - 🐟🐠🐡 comparative genomics/ethology & evolutionary cell biology of sleep 💤 😴 + adventures with @hilsawh - https://shafer-lab.netlify.app/

1.4K followers2.5K following59 posts

Maxwell Shafer reposted

Jack Stack
@jackstack.bsky.social

Hot off the presses! I reviewed the history of early ray-finned fishes, with a focus on their morphology, fossil record, and taxonomy. My principal goal is a guide for other workers to make the rich record of early actinopterygian evolution more broadly available. dx.doi.org/10.1002/jmor...

dx.doi.orgThe Evolutionary History of Early Ray‐Finned Fishes (Pan‐Actinopterygii)Ray-finned fishes, the most diverse living vertebrate clade, include over 600 extinct early actinopterygian species whose evolution is an enigma.

Maxwell Shafer reposted

Bob Wong
@bbmwong.bsky.social

Monash University is offering a fully-funded PhD scholarship to an outstanding student in animal behaviour/evolutionary ecology. Choose from eight project areas. For information about what project I'm offering, please DM me or see application form: forms.gle/ia9t4KPD3FKT.... Deadline: 15 Nov.

Maxwell Shafer reposted

Miguel Ramalho-Santos
@mrsantos.bsky.social

We are recruiting at the Lunenfeld-Tanenbaum Research Institute (LTRI) and the University of Toronto! In the areas of Reproduction, Pregnancy and Developmental Biology, at Assistant or Associate Professor level. Deadline: Nov 29, 2026 Find more and apply👇: 🔗 apply.interfolio.com/192324

Maxwell Shafer reposted

Brain Canada
@braincanada.bsky.social

Brain Canada is thrilled to announce the new cohort of Future Leaders in Canadian Brain Research. This year, 26 researchers join this growing community, and each receive $100,000. 🎉 Congratulations to the recipients! Find out more about this year’s Future Leaders ➡️ braincanada.ca/about/news-u...

Maxwell Shafer reposted

WeberLab@McGill
@weber-lab.bsky.social

🚨We're hiring!!🚨 @biomcgill.bsky.social is looking for a Quantitative Cell Biologist to join our diverse and interdisciplinary community. Please share this ad broadly, and reach out if you have any questions. mcgill.wd3.myworkdayjobs.com/en-US/McGill...

mcgill.wd3.myworkdayjobs.comAssistant Professor in Quantitative Cell Biology - Department of BiologyPlease refer to the How to Apply for a Job (for External Candidates) job aid for instructions on how to apply. If you are an active McGill employee (ie: currently in an active contract or position at ...

Maxwell Shafer reposted

Alex Schier
@schierlab.bsky.social

What regulates the urge to sleep? William Joo and colleagues identified brain regions that reflect how long mice have been awake. Strikingly, inhibiting one of these regions reduces sleep by 70%, without the major behavioral deficits associated with sleep deprivation. www.nature.com/articles/s41...

nature.comWake-activated neuronal populations that regulate sleep drive - NatureWhole-brain activity mapping, targeted cell manipulations and electrophysiology in mice identify wake-activated neuronal populations that are crucial for sleep drive and can persistently red...
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Maxwell Shafer
@maxshafer.bsky.social

My favourite result from the paper: the effect of these cues is so potent that even just the visual cue of a shell alone (physically separated from the fish) was enough to convert female N. brevis from 🌙 nocturnal to ☀️ diurnal!

Maxwell Shafer
@maxshafer.bsky.social

The effect we describe here is called 'circadian masking', where the presence of a cue 'masks' the output of the circadian clock - this differs from entrainment (e.g. jetlag) in that it has an immediate effect. We think masking might be involved in the evolution of activity patterns in these fish!

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Maxwell Shafer
@maxshafer.bsky.social

In our previous study on cichlids (www.nature.com/articles/s41...), we noted that, contrary to expectations, shell dwelling cichlids were strongly nocturnal - in that study, we used a "common garden" approach that didn't include enrichment or the shells those fish naturally live and breed in...

nature.comWidespread temporal niche partitioning in an adaptive radiation of cichlid fishes - Nature Ecology & EvolutionAn analysis of behavioural, eco-morphological and genomic data in 60 species of Lake Tanganyika cichlids reveals a remarkable diversity of temporal activity patterns across species, suggesting that te...
Maxwell Shafer
@maxshafer.bsky.social

First, we confirmed that these fish are diurnal in Lake Tanganyika. Then, using a combination of behavioural manipulations, we show that both shells and conspecifics can control circadian rhythms in these fish. Their effects dependent on species, life history, sex, and domestication!

Maxwell Shafer reposted

Jessica Arbour
@fountainscholar.bsky.social
Maxwell Shafer@maxshafer.bsky.social

This is such a strong effect (Fig 4-5 from the manuscript) - 6 additional female PhD students by promoting 1 woman! Also looks like a positive effect on male PhD students and their retention in science as well (compared to male promotions).

Maxwell Shafer reposted

Agneesh Barua
@agneeshbarua.bsky.social

How can a shared developmental programme generate the extraordinary diversity of teleost fishes? Our study suggests that the answer lies in the combination of conservation of network architecture, coupled with evolutionary flexibility in gene copy number. (1/8) doi.org/10.64898/202...

doi.orgAn evolvable and functionally partitioned network underlies developmental remodelling in teleostsComparative embryology has revealed that early animal development is based on highly conserved genetic programs. Beyond embryogenesis however, animals undergo remarkably diverse post-embryonic developmental transitions such as metamorphosis. Whether these transitions are also organised into conserved genetic programs remains largely unexplored. To identify conserved genetic programs underlying post-embryonic development, we examine metamorphic remodelling in five teleost fishes, spanning 200 million years of evolution. By integrating comparative co-expression networks, evolutionary genomics, phylogenetic modelling, and functional data in zebrafish, we uncovered a conserved post-embryonic developmental network. This conserved network comprises components involved in core cellular processes, and involved in development and physiology, both of which are under the control of thyroid hormone during metamorphosis. Despite evolutionary conservation at the coding sequence level, this network exhibits significant turnover in gene family copy number following the teleost-specific whole-genome duplication as well as lineage-specific expansions and contractions. The variation in gene copy numbers is associated with macroevolutionary variation in a number of ecological and morphological traits, including swimming performance and trophic level. Cross-species tissue expression, zebrafish single-cell transcriptomics, and zebrafish perturbation phenotypes placed the implicated genes in biological contexts relevant to these traits. Together, our results provide evidence of an ancient, functionally partitioned post-embryonic developmental network that has diversified throughout teleost evolution. The heterochronic variation in network function, changes in endocrine activity, and gene-family turnover provide potential routes through which a shared developmental architecture contributed to the evolution of phenotypic diversity in teleosts. ### Competing Interest Statement The authors have declared no competing interest. International Human Frontier Science Program Organization, LT0063/2022-L
Maxwell Shafer
@maxshafer.bsky.social

This is such a strong effect (Fig 4-5 from the manuscript) - 6 additional female PhD students by promoting 1 woman! Also looks like a positive effect on male PhD students and their retention in science as well (compared to male promotions).

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Maxwell Shafer reposted

Nadia Drake
@nadiadrake.bsky.social

A few months ago, I got a bit obsessed with a question about life on Mars: When—or if—“life” becomes the most parsimonious explanation for a handful of potential biosignatures, how will we know? Would we even admit it? This story grew from that question. www.scientificamerican.com/article/has-...

scientificamerican.comHas NASA already found life on Mars?In searches for past and present Martian life, some scientists say we’ve been too cautious to see what’s right in front of us

Maxwell Shafer reposted

Lauren Sumner-Rooney
@laurensr.bsky.social

📢 Heads-up: I'm currently finalising the job description for a 30-month postdoc modelling visual abilities in these very gorgeous and very dead creatures! If you're interested, please get in touch - anticipated start is late 2026/early 2027 and the project combines great colleagues in UK + S Korea!

Lauren Sumner-Rooney@laurensr.bsky.social

So excited to have received an #HFSPResearchGrant to study trilobite eyes with Luke Parry @oxuniearthsci.bsky.social and Gil Ju Lee (Pusan National University)!🥳 I'll be recruiting a postdoc @bristolbiosci.bsky.social - if 3D data, optical modelling, and fossils tickle your interest, stay tuned!

Maxwell Shafer reposted

Bob Wong
@bbmwong.bsky.social

Do you have a background in behavioural ecology and are you interested in doing a PhD in Australia? I’m looking for new grad students so check out our website (BobWongLab.org) or come find me in Torino at #ISBE2026. 🐟🐠

Maxwell Shafer reposted

Rishi De-Kayne
@rishidekayne.bsky.social

Our team at @arcadiascience.com is hiring! We're looking to hire a computational evolutionary biologist interested in asking how and why protein sequences/structures/functions differ across the tree of life 🧬 jobs.lever.co/arcadiascien... Please share widely!

jobs.lever.coArcadia Science - Platform Scientist: Comparative Protein EvolutionA Bit About Us: We're Arcadia Science, an evolutionary biology company founded and led by scientists. Our mission is to turn natural innovations into real-world solutions by developing systematic and ...

Maxwell Shafer reposted

Tessa Montague
@tessamontague.bsky.social

Do you know an outstanding aquarist? We're hiring a Senior Aquarist to help run our cephalopod facility at Columbia University. Our team maintains a colony of 250+ cuttlefish, develops new husbandry techniques (inc transgenics) & studies cuttlefish camouflage and social behavior. 1/3 [Pls repost!]

Maxwell Shafer reposted

Justus Kebschull
@justuskebschull.bsky.social

POINTseq, now out in Neuron after peer review. Read it. There are barcodes, viruses, and dopamine. Congrats to @hyopilkim.bsky.social on leading our lab's first published paper!

Neuron@cp-neuron.bsky.social

dlvr.itPOINTseq: Cell-type-specific barcoding reveals single-cell projection architecture of the mouse dopaminergic systemKim et al. introduce POINTseq, a high-throughput barcoded connectomics method for mapping brain-wide single-neuron projections of a specific cell population defined by common viral-genetic tools. Applying POINTseq to mouse midbrain dopamine neurons reveals diverse connectomic cell types and stereotyped collateral wiring patterns that may underlie distinct dopamine functions.

Maxwell Shafer reposted

Yunlu Zhu
@yunluzhu.bsky.social

Anyone else experiencing this cross-species yawn contagion?

Maxwell Shafer@maxshafer.bsky.social

Have you ever wondered if fish yawn? (and if they do, what that tells us about yawning?) The first preprint from the lab and a serendipitous observation ⬇️ www.biorxiv.org/content/10.6...

Maxwell Shafer reposted

Zebrafish Rock! 🎃
@zebrafishrock.bsky.social

Nothing boring about this preprint! 🥱🐠

Maxwell Shafer@maxshafer.bsky.social

Have you ever wondered if fish yawn? (and if they do, what that tells us about yawning?) The first preprint from the lab and a serendipitous observation ⬇️ www.biorxiv.org/content/10.6...

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Maxwell Shafer
@maxshafer.bsky.social

Overall, our results support multiple roles for yawning, with different functions in males versus females, and during different times of day. In future, we hope to identify yawns across many species (~60) to do more comparisons and identify genetic links to yawning!

Maxwell Shafer
@maxshafer.bsky.social

Many thanks to the STEM Fellowship, all our high school volunteers - Jaden, Vasu, Rita, Purvi, Sam, and Casey - as well as Ayasha, one of my first grad students, and who put it all together!

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Maxwell Shafer
@maxshafer.bsky.social

They yawned A LOT! Mostly at night, associated with staying awake, but also during the day, where we observed strong evidence for yawn contagion for the first time in fish! My favourite video ❤️⬇️

Maxwell Shafer
@maxshafer.bsky.social

When we recorded activity patterns and sleep in cichlids previously, this gave us 10s of thousands of hours of video, and we noticed things, including that many fish yawned! www.nature.com/articles/s41...

nature.comWidespread temporal niche partitioning in an adaptive radiation of cichlid fishes - Nature Ecology & EvolutionAn analysis of behavioural, eco-morphological and genomic data in 60 species of Lake Tanganyika cichlids reveals a remarkable diversity of temporal activity patterns across species, suggesting that te...

Maxwell Shafer reposted

Tschopp Lab
@tschopplab.bsky.social

One of my dream projects, ever since joining here in Basel, out now in @nature.com : single-cells 🤝 eco-morphological proxies rdcu.be/fiyso How cells and tissues adapt to dietary niches... Thanks and congrats to Antoine, Walter, and all the other co-authors for this great collaboration!! 🙏🥳

rdcu.beAdaptive cellular evolution in the intestine of hyperdiverse cichlid fishesNature - Single-cell transcriptomics combined with morphological and ecological data show that the rapid evolutionary radiation of cichlid fishes in Lake Tanganyika was accompanied by dietary...

Maxwell Shafer reposted

Claire Bedbrook
@clairebedbrook.bsky.social

Aging may feel gradual… but what if it’s not? In our recent paper, we tracked fish continuously from puberty until death. This gave us a unique view of how aging unfolds across the adult lifespan. 🧵