tag:blogger.com,1999:blog-3653345901774701895.post5056003446708408347..comments2024-03-23T12:02:36.626-07:00Comments on Mark P. Witton's Blog: Megafuzz under the microscope: how credible are restorations of giant fluffy extinct animals?Mark Wittonhttp://www.blogger.com/profile/02524696111911168322noreply@blogger.comBlogger41125tag:blogger.com,1999:blog-3653345901774701895.post-58648388849459467562020-10-22T00:36:28.759-07:002020-10-22T00:36:28.759-07:00I am looking for an Business related blog, And see...I am looking for an Business related blog, And see your blog and it is really nice and have some great information.<br />Nice to read your articles.<br /><br />Zanac Life Science is a Veterinary Medicine Company in India<a href="https://zanaclifescience.com/powermix-gold.php" rel="nofollow">Powermix Gold</a><br />manufacturer of Veterinary product Powermix Gold, Liquid Feed Supplement, Liquid Feed Supplement of Vitamins for Cattle & Poultry FeedingInflux Infotechhttps://www.blogger.com/profile/06161829462617985433noreply@blogger.comtag:blogger.com,1999:blog-3653345901774701895.post-40869001260806402622020-08-27T11:31:52.043-07:002020-08-27T11:31:52.043-07:00Is it worth qualifing Megatherium as a "typic...Is it worth qualifing Megatherium as a "typicall placental mammal"? when it itself is a xenarthan and extant xenarthans have lower metabolic rates than estimated for ther size<br />Also with rhinos, all extant rhinos live in tropical areas, why is the sumatran rhino the only one that grows hair? is because it's smaller? or their hair doesn't have much to do with thermoregulation?yourselfhttps://www.blogger.com/profile/12836116811341509432noreply@blogger.comtag:blogger.com,1999:blog-3653345901774701895.post-87884641058758253202020-02-24T05:23:21.919-08:002020-02-24T05:23:21.919-08:00One thing possibly worth mentioning is that there ...One thing possibly worth mentioning is that there are lower limits to viable temperatures for immediately subcutaneous tissue that isn't at core body temperature. So animals which live in temperate to arctic areas which have absolutely no fur might well be within their core thermal TNZ but still be prone to frostbite. Humans with good insulation can survive in the coldest Siberian winters, but any extremities, such as fingers or noses, become very vulnerable to frostbite.Pds3.14https://www.blogger.com/profile/01042151103642336762noreply@blogger.comtag:blogger.com,1999:blog-3653345901774701895.post-81734740885372914512020-02-24T04:59:33.109-08:002020-02-24T04:59:33.109-08:00Glyptodon has a pretty beefy tail TIP...
There mig...Glyptodon has a pretty beefy tail TIP...<br />There might be some prehensile-tailed mammals that have very thick tails. Some lemurs have almost reptilian-looking tails.<br /><br />Kangaroos have somewhat thick tails.<br /><br />Giant Anteaters have very dinosaurian-looking tails that stick straight back, but they're a lot thinner-looking if you ignore the long crest of hair. In fact, now that I think about it, they're shockingly ornithopod-looking for a mammal with little obvious convergence in their lifestyles and a weight difference of a factor of 100 or so.<br /><br />Wooly monkeys have thick tails, but they're thinner without the wool.Pds3.14https://www.blogger.com/profile/01042151103642336762noreply@blogger.comtag:blogger.com,1999:blog-3653345901774701895.post-23090666222153827112020-02-24T04:16:32.571-08:002020-02-24T04:16:32.571-08:00"The National Research Council (1981) reports..."The National Research Council (1981) reports that a sheep with a 10 cm thick fleece has a LCT of -120°C(!)"<br /><br />Whoa..... that's absurdly cold. I had to do a double take. So the idea of leaving a sheep outside with a bunch of food in central Antarctica over the winter is actually fairly reasonable.<br /><br />This greatly improves my opinion on moving to Titan with livestock.Pds3.14https://www.blogger.com/profile/01042151103642336762noreply@blogger.comtag:blogger.com,1999:blog-3653345901774701895.post-2771665225558439052020-02-03T12:32:34.589-08:002020-02-03T12:32:34.589-08:00I know this is a little late, but I think the reas...I know this is a little late, but I think the reason this is such a hot topic is because with all the large animals we DO know the integument of, they either lived in extremely hot tropical environments (such as elephants, rhinos, hippos, various large dinosaurs), or freezing cold environments (woolly mammoths, woolly rhinos). We don't really have a good idea about the integument of the giant animals in middle-ground temperate environments that are neither super hot OR super cold, at least not year-round. The closest comparisons we have are probably bison, but they're still small compared to a lot of prehistoric animals they shared their environment with. That's why the animals we see the most debate over integument consist of animals from temperate climates such as Pachyrhinosaurus, megasloths, Columbian mammoths, and that kind of thing.Pelagornishttps://www.blogger.com/profile/08702848896692862732noreply@blogger.comtag:blogger.com,1999:blog-3653345901774701895.post-5491520615772668762019-11-23T19:46:50.039-08:002019-11-23T19:46:50.039-08:00But such studies must be mostly conjecture. The ev...But such studies must be mostly conjecture. The evidence is extremely scarce either way.Gandalfhttps://www.blogger.com/profile/02539597354486559694noreply@blogger.comtag:blogger.com,1999:blog-3653345901774701895.post-10112158240353996222019-11-12T14:39:26.561-08:002019-11-12T14:39:26.561-08:00That second sentence should have said "People...That second sentence should have said "People don't often draw or talk about an inbetween, even through in real life there are many animals that are covered in short fine hair without being either naked/mostly-naked or fluffy"Feliformahttps://www.blogger.com/profile/13193307410551834573noreply@blogger.comtag:blogger.com,1999:blog-3653345901774701895.post-35279246171580349782019-11-08T09:56:03.989-08:002019-11-08T09:56:03.989-08:00What about giant pterosaurs? You have consistently...What about giant pterosaurs? You have consistently mentioned that they probably didn't need to be fuzz-less, but we know flying foxes and some large birds are extremely vulnerable to overheating.Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-3653345901774701895.post-32951733846690327572019-11-06T18:43:59.505-08:002019-11-06T18:43:59.505-08:00Yeah, the whole zone is more important than just t...Yeah, the whole zone is more important than just the spot of neutrality, it seems like an oversight...Francelino de Azevedohttps://www.blogger.com/profile/13126827580881531192noreply@blogger.comtag:blogger.com,1999:blog-3653345901774701895.post-14200372324322667372019-11-06T13:13:56.395-08:002019-11-06T13:13:56.395-08:00I'm wondering if given the difficulties you me...I'm wondering if given the difficulties you mentionned for large sauropods to shed heat the skin-flaps we see on some reconstructions (like this painting https://svpow.files.wordpress.com/2012/12/tumblr_mdqur507ge1rgw4eto1_500.jpeg by Emiliano Trocco)are more likely now ? In a similar way to ear-flaps on Elephants ?Peredhelhttps://www.blogger.com/profile/10131736977501925459noreply@blogger.comtag:blogger.com,1999:blog-3653345901774701895.post-49464750788152425052019-11-05T06:24:57.051-08:002019-11-05T06:24:57.051-08:00Ostrich feathers are a lot sparser than they appea...Ostrich feathers are a lot sparser than they appear (see pics here http://dinogoss.blogspot.com/2011/02/heat-feathers-and-half-arsed.html). They seem to be an example of the kinds of long but thinned out and sparse integument useful for shading while still heat shedding Mark discusses in this article.Matt Martyniukhttps://www.blogger.com/profile/04220900229537564466noreply@blogger.comtag:blogger.com,1999:blog-3653345901774701895.post-76377036305389310252019-11-04T18:21:20.068-08:002019-11-04T18:21:20.068-08:00Can't say too much but there may be new data e...Can't say too much but there may be new data emerging about that.....Adam Yateshttps://www.blogger.com/profile/03046084686097124394noreply@blogger.comtag:blogger.com,1999:blog-3653345901774701895.post-33027658973228975492019-11-04T02:54:44.212-08:002019-11-04T02:54:44.212-08:00Yes, air sacs are useful for cooling down birds, a...Yes, air sacs are useful for cooling down birds, and the same was probably true of dinosaurs. But even so, we see that ostriches are reliant on having featherless regions for cooling: their naked legs, heads and necks are critical sites for dumping heat.Mark Wittonhttps://www.blogger.com/profile/02524696111911168322noreply@blogger.comtag:blogger.com,1999:blog-3653345901774701895.post-15328300043601125052019-11-04T02:45:11.553-08:002019-11-04T02:45:11.553-08:00This is why I mentioned Fariña's papers could ...This is why I mentioned Fariña's papers could do with expansion. The results are interesting, but they also raise a lot of questions about the impact of the variables he used, their application to different animals etc. It would also be neat to see TNZs calculated for some fossil animals, rather than just thermal neutral figures, as these would give more useful insights into climate tolerances.Mark Wittonhttps://www.blogger.com/profile/02524696111911168322noreply@blogger.comtag:blogger.com,1999:blog-3653345901774701895.post-91876251026623868722019-11-03T14:44:45.887-08:002019-11-03T14:44:45.887-08:00Another question: what about Diprotodon? That mars...Another question: what about Diprotodon? That marsupial weighed three tons, the size of a rhino, lived in the hot parts of Australia, and yet we know from footprints it had fur similar to its modern wombat relatives.Pelagornishttps://www.blogger.com/profile/08702848896692862732noreply@blogger.comtag:blogger.com,1999:blog-3653345901774701895.post-88746695885438470422019-11-03T12:45:54.731-08:002019-11-03T12:45:54.731-08:00Also giraffes come to mind too a living animals th...Also giraffes come to mind too a living animals that's not either.<br /><br />Weirdly, pterosaurs seem to be a notable exception to "fluffy vs mostly-naked only" trend in paleoart. There's lots of art of them that's neither.Feliformahttps://www.blogger.com/profile/13193307410551834573noreply@blogger.comtag:blogger.com,1999:blog-3653345901774701895.post-64517891758400549362019-11-03T12:33:58.031-08:002019-11-03T12:33:58.031-08:00Something that bothers me with restorations and di...Something that bothers me with restorations and discussions of which integument to go with, is that it's always naked (or mostly naked) vs fluffy. There's an in-between even though in real life there are many animals that are covered in very short fine hair, but are not at all fluffy besides occasional manes and tails (horses, cows and lions come to mind). There's also how different species of wild pigs can vary between extensive hair covering and mostly naked, but can also be neither.<br /><br />This trend of naked-vs-extensive hair is especially noticeable with extinct elephant and rhino restorations. They always seem to be portrayed as just either super woolly or mostly naked. There's rarely just light covering of hair.<br />Feliformahttps://www.blogger.com/profile/13193307410551834573noreply@blogger.comtag:blogger.com,1999:blog-3653345901774701895.post-57814418950341825152019-11-03T11:12:22.835-08:002019-11-03T11:12:22.835-08:00(In-case it wasn't clear, referring to the sca...(In-case it wasn't clear, referring to the scaly nature of Psittacosaurus, given it only has potential feather homologues on it tail; ironically one of the few non-fuzzy parts of Kulindadromeus)Amber Littlehttps://www.blogger.com/profile/04687388353006696077noreply@blogger.comtag:blogger.com,1999:blog-3653345901774701895.post-68458074678784235102019-11-03T11:08:08.712-08:002019-11-03T11:08:08.712-08:00Not entirely on topic, but I'm curious as to y...Not entirely on topic, but I'm curious as to your thoughts on Psittacosaurus. We frame all these discussions about feather loss on large animals overheating, but this is a cat sized animal, with ancestors no larger, in a cool enough environment, which per Kulindadromeus has feathers at some point in its ancestry. (All assuming the rumored fuzzy juvenile never comes to fruition). Obviously there must be other factors at play here.Amber Littlehttps://www.blogger.com/profile/04687388353006696077noreply@blogger.comtag:blogger.com,1999:blog-3653345901774701895.post-50778977630228634192019-11-02T12:00:09.902-07:002019-11-02T12:00:09.902-07:00Very interesting post. Has any work been done on l...Very interesting post. Has any work been done on large birds? I know an ostrich isn't as big as the animals mentioned here but they are have a LOT of feathers for their climate. Could air sacs, large lungs and hollow bones help with shedding heat in the giant dinosaurs they way they do in birds?Diana/ Garden on the Edgehttps://www.blogger.com/profile/08532154058903038177noreply@blogger.comtag:blogger.com,1999:blog-3653345901774701895.post-53699755132327815092019-11-02T10:49:38.732-07:002019-11-02T10:49:38.732-07:00I'm intrigued by those -4ºC hairless and -28ºC...I'm intrigued by those -4ºC hairless and -28ºC with 4cm hair thermal neutralities for Mylodon. With the scaling rules stated in the article regarding body shapes (they lessen in influence with more mass) and insulation (it increases in influence with more mass), I feel like these calculations would make some animals completely unviable. Modern rhinoceroses are about the same weight as Mylodon and they clearly live in far warmer temperatures than -4ºC. Even if their shapes could explain some changes in the final temperature, the results shouldn't be that different given their large mass, which diminishes the influence of body shape. And wooly mammoths, which we know have a wooly underfur that can go to 8cm, would be boiling even in the winter of their pleistocene steppes, as they'd probably get a far lower thermal neutrality than the already extremely low -28ºC for Mylodon. I'm a layman in biology, I haven't seen the actual calculations and I know that I'm definitely missing something here, mind you. I just want to know what.Francelino de Azevedohttps://www.blogger.com/profile/13126827580881531192noreply@blogger.comtag:blogger.com,1999:blog-3653345901774701895.post-46905414046786714272019-11-02T07:05:59.874-07:002019-11-02T07:05:59.874-07:00Lovely and thorough article! I will now imagine mo...Lovely and thorough article! I will now imagine most huge prehistoric animals as (mostly) hairless/featherless. Another reason why it's such a pity only so few terrestrial mammalian behemoths are still around: it makes it difficult to ascertain whether 'hairless'elpehants and rhinos are outliers or typical. It seems 'typical' is the more likely option.<br /><br />As for secondarily fuzz-less dinosaurs, that does seem like the most likely scenario to me and one can imagine how serious the selective pressure to lose integument must have been for an (I here assume) fuzzy lineage so prone to evolve into giants must have been. Given our knowledge of scaly sauropod embryos, that also begs the question if this hypothetical re-evolving of scaliness in adults, developmentally 'forced' the juveniles into same, despite that perhaps not being as advantageous to them as to their adult counterparts. <br />One last thing I'd like to mention is this: some of the unease we might feel regarding larger dinosaurs becoming scaly again could be that birds are our reference frame and, simply, no bird we know ever got so big that it needed to become scaly again, as many other dinosaurs might have had to. Therefore it may seem 'illogical' to us. Birds might perhaps lose their feathery coats too if they ever became big enough for that to be a viable or even vital strategy. As it is, all living birds (and most likely all known extinct ones) are simply within the fuzzy range of dinosaur mass and therefore fuzzy. Nevertheless, I think it is worth mentioning that the largest birds we have around today sport very thin or absent feathering on their necks, plus mostly naked legs. Incipient 'defeathering' at work?BrianLhttps://www.blogger.com/profile/17880867575515761505noreply@blogger.comtag:blogger.com,1999:blog-3653345901774701895.post-11396511406577321832019-11-02T05:02:30.351-07:002019-11-02T05:02:30.351-07:00"I'm expecting a certain amount of harrum..."I'm expecting a certain amount of harrumphing about this article from some quarters, especially from those who - like me - quite like seeing big, shaggy animals in palaeoart. They look cool, give off that 'new palaeo' vibe and provide us with lots of fun and exciting looks to explore."<br /><br />And then we remember that the rest of Deinocheirus has been discovered, and the walking-carpet theme doesn't seem quite as necessary for all of that...Warren JBhttps://www.blogger.com/profile/11743987856127631574noreply@blogger.comtag:blogger.com,1999:blog-3653345901774701895.post-31577200874924435012019-11-02T04:59:28.205-07:002019-11-02T04:59:28.205-07:00It does give off that kind of 'hairless cat...It does give off that kind of 'hairless cat' vibe, doesn't it?Warren JBhttps://www.blogger.com/profile/11743987856127631574noreply@blogger.com