Indeed... one of the many mysteries we still have to unravel! We're super happy to share this paper led by @jcuofficial.bsky.social PhD candidate Joel Gayford!
Dr. Jodie Rummer
Marine Biologist, TEDx Speaker, and Fish Physiologist studying how fish are responding to climate change

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Watch my TEDx talk: Athletes of the Great Barrier Reef
With over 400 million years of evolution, fish represent one of the most successful adaptive radiation events in vertebrate history. Yet, we do not fully understand how fish are responding to environmental and human-induced stress and their capacity to adapt to global climate change.
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I love that not all #sharks even undergo TI (tonic immobility) because it makes it even more curious! There's so little info on all of this in general that any new info creates a lot of questions :) @physiologyfish.bsky.social 🧪 🦈 🐟 🦑 Recent paper about this: link.springer.com/article/10.1...

link.springer.com
We are super proud of this paper led by @jcuofficial.bsky.social PhD student @joelgaylard.bsky.social - so cool that #sharks follow these centuries-old mathematical scaling 'rules' almost perfectly!!
Come along to the Atrium on Weds at #SEB2025 to meet the team! 👋 With @andreafuller.bsky.social @physiologyfish.bsky.social @kruthsatz.bsky.social @conphysjournal.bsky.social & more. @sebiology.bsky.social
Further coverage - this time from phys.org - of the new paper from Joel Gayford and @physiologyfish.bsky.social that discusses why some (but not all) #sharks go into tonic immobility when flipped over share.google/UNtr8XAP7cNB...

phys.org
More coverage, this time from SciTechDaily, of paper from Joel Gayford and @physiologyfish.bsky.social on #shark size/surface area ratios scitechdaily.com/sharks-follo...

scitechdaily.com
You know how a #shark goes immobile or "tonic" when flipped over on its back? TIL that isn't true for all species. A new study from Joel Gayford and @physiologyfish.bsky.social says: three different orders of shark..seem to have all lost the ability to go into tonic www.jcu.edu.au/news/release...
‘Playing dead’ overrated for sharks, rays
‘Playing dead’ might be the key to survival for many species in the animal kingdom, but new research from James Cook University suggests it’s no great help for sharks and rays.
www.jcu.edu.au
Some sharks freeze when you turn them upside down – and there’s no good reason why... anymore. New study 📄 theconversation.com/sharks-freez... by Gayford & Rummer at @jcuofficial.bsky.social #sharkscience #evolution
Sharks freeze when you turn them upside down – and there’s no good reason why
Rather than a clever survival tactic, tonic immobility might just be ‘evolutionary baggage’.
theconversation.com
New @jcuofficial.bsky.social study — tonic immobility in sharks may be ancient evolutionary baggage — not a survival trick. 📄 doi.org/10.1007/s111... Some sharks freeze when flipped over. Does it help them survive? Probably not. Maybe leftover from their ancient ancestors. #SharkScience #Evolution

doi.org
Great article written by Joel Gayford & @physiologyfish.bsky.social on our recent paper in Royal Society Open Science Journal using #3D models to study shark scaling. Credit also to co-authors Johnson Martin & Andrew Chin as well. theconversation.com/sharks-come-...
Sharks come in many different shapes and sizes. But they all follow a centuries-old mathematical rule
A new study proves for the first time that the ‘two-thirds scaling law’ applies to large animals as well as small ones, offering key lessons for conversation.
theconversation.com
New paper out today! 🦈 We tested whether blacktip reef shark dorsal fins are reliable for photo ID – they are! ✅ Stable over time ✅ Unique among individuals 📍Long-term dataset from French Polynesia Led by Physioshark 🔗 doi.org/10.1111/jfb.... #SharkScience #MarineBiology @jcuofficial.bsky.social
This very likely has some important implications for reconstructing Carcharocles megalodon!
🦈 #shark A new study from JCU researchers Joel Gayford and @physiologyfish.bsky.social has examined the surface area to volume ratio of 54 species of shark, finding that it tends to follow the same trend we expect to see for individual cells royalsocietypublishing.org/doi/10.1098/...
royalsocietypublishing.org
Further coverage, this time from The Conversation, of new paper Joel Gayford and @physiologyfish.bsky.social showing that "sharks seem to converge on the same basic body plan when it comes to surface area and volume"
Sharks: 450 million years of toothy excellence, still following a centuries-old geometry rule. Meanwhile, you’re still using that “passionate self-starter” line on your resume. Excellent shark content & summary of a new study! #OceanHoptimism #SharkMath #EvolutionaryFlex #UpdateYourResume
Sharks come in many different shapes and sizes. But they all follow a centuries-old mathematical rule theconversation.com/sharks-come-...
Sharks come in many different shapes and sizes. But they all follow a centuries-old mathematical rule
A new study proves for the first time that the ‘two-thirds scaling law’ applies to large animals as well as small ones, offering key lessons for conversation.
theconversation.com
Sharks just proved the 2/3 scaling law. 🦈📏 Using 3D modelling of 54 species, we found sharks follow the expected surface area-to-volume relationship almost perfectly — validating a key physiological theory. 📄 doi.org/10.1098/rsos... 📸 Rachel Moore 📍 @jcuofficial.bsky.social #SharkScience #shark

doi.org