Dave Marshall

@ChristosA89 @NatSciChannel In agreement. This study doesn't refute the effects of 0₂ concentration, only shows that it isn't a control in modern insects. There are so so many other controls and variables that need to be considered. Limits on tracheole density/width/length?

I made a post a few hours back which may answer your points in more depth (attached). Direct answer to your point 1, there is linear scaling with slight increase over mean (x1.8 factor). This does scale well in my opinion, without invoking non linear exponential growth in tracheole density. Direct answer to point 2, I wrote in attached post how chemical potential gradients alone satisfy scaled up oxidative phosphorylation rate by passive diffusion alone. Therefore I imagine a scenario where mutations arise randomly that increase tracheole density, however selection is relaxed for said iterations as passive diffusion alone satisfies the same rate of throughput without more energy expenditure (ie those with linearly scaled tracheoles/spiracles). This by the way assumes there were mutations that could increase tracheole density despite other tradeoffs, regardless of space not utilised. x.com/ChristosA89/st…

🚨NEW STUDY DROP🚨 This team puts forth strong evidence Oxygen has little to do with how big an insect can get! Throw away that old myth as giant insects like Meganeuropsis didn't increase their lung capacity despite being the size of a small eagle! 🎨: Mark Witton

@ChristosA89 @NatSciChannel Uses that lack of optimisation in modern insects as the evidence that 0₂ availability isn't a constraint but doesn't consider any other controls on tracheole density: Extrapolate! Giant bugs are just small bugs but bigger! Doesn't consult fossil record other than for body size.

@ChristosA89 @NatSciChannel Compares modern body size : tracheole volumetric density (%) and linearly extrapolates average to Meganeuropsis size. - Why doesn't it scale well if O₂ is a limit? Considers available space for more tracheoles that isn't utilised. - If O₂ is limit why not increase the density?

@Palaeocast [Happy Jawless fish noises] #fish #palaeo #paleontology #evolution #fossil #agnathan #aglaspidid #gnathostome #chondrichthyes #sensoryecology #teeth #sacabambaspis

Ep 166: Origin of teeth Pt1 palaeocast.com/origin-of-teet… We find the evolutionary origin of our teeth not in the mouths of early fish, but in their external skeletons! In fact, teeth evolved well before jaws did! But what were they for? #fossilfriday #paleo #palaeontology #podcast

Took me way too long to get this out, but here we go: Seven hours of multimedia content. From mud to museum, you get to see as complete a representation of a large-scale palaeontological dig as possible.

Merry xmas to @SWTD_Game. I am currently sat on an oil rig on Christmas day patiently awaiting horrors beyond comprehension. Thanks guys. At least we have this to eat!

@TetZoo Oh dear me. Sorry you're still having to deal with him.

One of the 'pterosaurs in amber' guys (if you know, you know) has produced lots of AI garbage featuring 'pterosaurs in amber', because of course he has. It gets better: he thinks that David Peters is authoritative and a reliable source, more than I am, naturally. And thus...

@JoschuaKnuppe Remember, they were heckin' chonkers! Amazing that you got the fire in the background. First thing I always try to crowbar into a documentary.

Time for some large eurypterid in here! #Paleostream! twitch.tv/paleostream

@aadineen I wonder how much stuff we could add to the Self Care Room whilst still maintaining the vibe.

GSA's self care room is really leaving a lot to be desired 😄

@paleozoey @TomHoltzPaleo @terrapean Oh wait, you meant Nigel Marvin didn't you?

@paleozoey @TomHoltzPaleo @terrapean The optics of compound eyes means that whilst trilos & eurys would indeed be able to bring the rings into focus, they probably wouldn't have had high enough resolution to be able to perceive them - dependent on where the ring lay around Earth I guess. Don't trust their reporting.

And yet, no one in the historical record ever mentioned the earth having a planetary ring. Curious. (I hate theoretical astrophysics)

@DMcEdiacaran Has someone targeted this because it's known to be important or is it just some random rock surface to them?

@JoschuaKnuppe Holy moly. Their attitude is just so so wrong. I understand that finding good images for cover art can be difficult, but AI is not the answer. Not for something super specific like anatomy. Especially not for science communication.

A podcast that doesn't put the same amount of care into sourcing its images as it does with its literature is kind of ironic and sad. And they are even aware of some of AI shortcomings. You know what wouldn't fall into these easy to avoid problems? A human mind.

Ep162: Cerney Wick palaeocast.com/cerney-wick/ We've been invited to participate in some Jurassic/Ice Age fieldwork in this special episode with Sally and Nev Hollingworth. #TuskForce #Quaternary #Jurassic #Mammoth #Ammonite #Podcast #Paleontology #Paleo #Fossils #Evolution

@ArminReindl You're welcome! :D

I audibly groaned. Side note I could see Ian McKellen pull of Baurusuchus perhaps

@april_b_arting My brain just churns them out. Glad one person on the internet enjoyed!

Why am I like this?

My video was one of the 10 winners in the @Nature Science in Shorts Competition! Shout out to @DaveJMarshall for his wonderful editing skills! Thanks to the @ESRFsynchrotron, @UU_University and especially the Stable Isotope Laboratory at @VUamsterdam youtu.be/Itvb2XpjQlY

Blog: Langebaanweg – A Cenozoic treasure trove in South Africa palaeocast.com/langebaanweg-1/ In the first instalment of this series, Brigette Cohen introduces us to Langebaanweg, a Mio-Pliocene lagerstätte from South Africa, and retells the history of its discovery. #Paleontology

@Sketchy_raptor How do I unfollow?

Boi