tag:blogger.com,1999:blog-8161161431451849208.post4821009359269816409..comments2024-03-18T02:43:22.233-07:00Comments on Antediluvian Salad: Spinosaurus Unauthorized I: Hippos Are Not Really Fat and Can't SwimDuane Nashhttp://www.blogger.com/profile/14467779935085970909noreply@blogger.comBlogger26125tag:blogger.com,1999:blog-8161161431451849208.post-41798465008480255732016-11-29T12:52:43.030-08:002016-11-29T12:52:43.030-08:00Thanks Katya glad you get something from them. Sor...Thanks Katya glad you get something from them. Sorry about grammatical errors.Duane Nashhttps://www.blogger.com/profile/14467779935085970909noreply@blogger.comtag:blogger.com,1999:blog-8161161431451849208.post-66492475573942724542016-11-26T08:43:55.713-08:002016-11-26T08:43:55.713-08:00Your articles are absolutely awesome, the "pu...Your articles are absolutely awesome, the "punting" Spinosaurus idea looks like it's very reasonable, and I agree with your points completely. There were a few grammatical errors, but I'm certainly showing this to my dinosaur-obsessed friends and give them a new and better theory to think about (mostly referring to your Spinosaurus-themed article). =)Anonymoushttps://www.blogger.com/profile/13448693694676227521noreply@blogger.comtag:blogger.com,1999:blog-8161161431451849208.post-60405756838690595712015-10-29T15:26:37.576-07:002015-10-29T15:26:37.576-07:00Based on the information in Van der Geer et. al.s ...Based on the information in Van der Geer et. al.s paper it is possible to come up with a theory that explains why dwarfed hippos are only found on Cyprus, Crete, Sicily and Malta, and Madagascar; but not on Corsica, Sardinia, the Cyclades or Dodecanese.<br />It also explains why hippos on the Archipelago de Bisagos, Mafia Island and Zanzibar are normal sized and have not destroyed all the vegetation on the islands by overpopulation despite the islands having been isolated from the mainland for thousands of years.<br /> It draws on the observations of hippos being swept out to see by tsunamis and flooding rivers and being found on coral reefs or shallow sandbanks; and of other hippos having to be rescued in a fishing boats net and towed to shore.<br />Also the report of a hippo on an isolated island in a large lake surrounded by deep water.<br /><br />It will be interesting to compare this with your next post.<br /><br />LeeB ;-).<br /> Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-8161161431451849208.post-49167447640161461292015-10-25T08:14:45.342-07:002015-10-25T08:14:45.342-07:00Thanks LeeB!! those refs are excellent. While I st...Thanks LeeB!! those refs are excellent. While I still maintain hippos can not swim in fresh/saltwater and from all the clips I have observed of baby hippos in the water they appear to sink straight down just like adults - i do have another surprise in store for my next post that allows the possibility of swimming dispersal in the hippos that colonized those islands. Stay tuned!!Duane Nashhttps://www.blogger.com/profile/14467779935085970909noreply@blogger.comtag:blogger.com,1999:blog-8161161431451849208.post-70934379737248669642015-10-25T04:06:22.410-07:002015-10-25T04:06:22.410-07:00You might want to look at the recent paper here: h...You might want to look at the recent paper here: http://www.researchgate.net/publication/264461046_If_hippopotamuses_cannot_swim_how_did_they_colonize_islands_A_reply_to_Mazza by Van der Geer et. al. who conclude that Hippos, especially juveniles may be able to swim in salt water, not only in the sea but even in saline lakes.<br /><br />LeeB.<br />Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-8161161431451849208.post-82268780383603206552015-10-20T15:07:27.770-07:002015-10-20T15:07:27.770-07:00@LeeB Good looking for answers!! The kapama page y...@LeeB Good looking for answers!! The kapama page you cite says that hippos can not swim... both of those blog posts seem a little less than ideal reference on hippo and I would check this out: http://darwin.wcupa.edu/~biology/fish/pubs/pdf/2009JM%20Hippo.pdf <br /><br />On baby hippo buoyancy I have heard that before but honestly don't think there is much rigorous stuff on the subject...<br /> <br />I will go into greater detail regarding that study but if you are further interested in hippos and how they move in water check it out. Spoiler - during all the scientists observation period the hippos were never observed to swim.Duane Nashhttps://www.blogger.com/profile/14467779935085970909noreply@blogger.comtag:blogger.com,1999:blog-8161161431451849208.post-64372836485291782002015-10-19T23:30:42.995-07:002015-10-19T23:30:42.995-07:00Also this site: http://www.kapama.co.za/rangerblog...Also this site: http://www.kapama.co.za/rangerblog/2012/08/the-majestic-hippo/ suggests they can actively control their buoyancy using their diaphragm; the comment also suggests they can float back to the surface gradually at will, this should suggest that they could float if not swim in salt water.<br /><br />LeeB. Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-8161161431451849208.post-29138683487665506822015-10-19T23:27:08.154-07:002015-10-19T23:27:08.154-07:00I found online a site which suggested that juvenil...I found online a site which suggested that juvenile hippos are more buoyant than adults and can swim here: https://animalcorner.co.uk/hippo-anatomy/<br /><br />LeeB.Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-8161161431451849208.post-38328552375588157582015-10-19T19:28:45.819-07:002015-10-19T19:28:45.819-07:00When I first proposed the belly-sliding hypothesis...When I first proposed the belly-sliding hypothesis after nat geo leaked some photos Andrea made a comment on my blog to the effect of a ventrally inclined head mere cm off the ground, so he did not suggest it for all spinosaurids actually but if you look at the skeletal mounts in the post many of them feature a very low slung animal with an atypical theropod stance and high neural spines over the pelvic area.<br /><br />linkhttp://antediluviansalad.blogspot.com/2014/08/did-bakker-get-spinosaurus-right-after.htmlDuane Nashhttps://www.blogger.com/profile/14467779935085970909noreply@blogger.comtag:blogger.com,1999:blog-8161161431451849208.post-81731141122960412442015-10-19T17:21:04.569-07:002015-10-19T17:21:04.569-07:00Oh and can you link me to where Andrea suggested s...Oh and can you link me to where Andrea suggested such posture?Iris-Katyayanihttps://www.blogger.com/profile/06188961246186305190noreply@blogger.comtag:blogger.com,1999:blog-8161161431451849208.post-33137733143578193742015-10-19T17:16:44.578-07:002015-10-19T17:16:44.578-07:00Could you link me to several skeletals that highli...Could you link me to several skeletals that highlight how you view their posture?Iris-Katyayanihttps://www.blogger.com/profile/06188961246186305190noreply@blogger.comtag:blogger.com,1999:blog-8161161431451849208.post-4592386557666259322015-10-19T14:34:17.428-07:002015-10-19T14:34:17.428-07:00@Khalil beiting. Andrea Cau from theropoda has sug...@Khalil beiting. Andrea Cau from theropoda has suggested this posture, the skeletal mounts - although mounts can be wrong - suggest this posture, and the straight neck and heavy clawed forelimbs might suggest a low slung neutral body. Several species also display high neural arches over the pelvic girdle possibly suggesting some type of tendinous bracing system. it should be noted this interpretation is far from consensus and many (most?) give these animals rather typical large theropod post cervical anatomy.<br /><br />Finally for me an ecology of relatively small animal foraging, pressure pit usage in the water this low slung anatomy makes sense.Duane Nashhttps://www.blogger.com/profile/14467779935085970909noreply@blogger.comtag:blogger.com,1999:blog-8161161431451849208.post-92115568426972543172015-10-19T14:23:06.441-07:002015-10-19T14:23:06.441-07:00@ LeeB good points however with the vast amount of...@ LeeB good points however with the vast amount of hippo enclosures including underwater viewing glass I think someone would have recorded images of hippos dog paddling by now... but points taken regarding salt water and age classes. I am going to discuss this further in my next post where researchers actually analyzed hippo gait underwater. They recorded several hundred hours of observation and never once observed active swimming in the hippos i.e. dog paddling,<br /><br /><br /><br />Duane Nashhttps://www.blogger.com/profile/14467779935085970909noreply@blogger.comtag:blogger.com,1999:blog-8161161431451849208.post-52948710106868718782015-10-19T13:52:39.237-07:002015-10-19T13:52:39.237-07:00That makes sense. I can understand how the average...That makes sense. I can understand how the average person can automatically assume that they were "ordinary", but once you delve into their anatomy and ecology than Baryonychines turn from storks into long-legged crocodilians. Also, what makes you think that they were tilting downards? I'm not doubting you, it's just that I'm truely curious.Iris-Katyayanihttps://www.blogger.com/profile/06188961246186305190noreply@blogger.comtag:blogger.com,1999:blog-8161161431451849208.post-32606168050013215452015-10-19T04:06:51.810-07:002015-10-19T04:06:51.810-07:00@khalil beiting thanks my hunch is that baronychin...@khalil beiting thanks my hunch is that baronychines might be towards the tapir range of aquatic adaptation i.e. thickened dermis. They have not developed thickened bone/extreme barrel chest but they were comfortable in the water and even did some underwater running. Everyone always says baronychines have "normal" theropod stance and legs but I disagree. They were probably pitched forward to a weird degree in stance that when walking the snout and forelimbs were mere centimeters off the ground (as in skeletal mounts) and there legs are towards the lower end of leg length in large theropods (see figure in supp info Ibrahim et al.) . I believe we don't have complete metatarsals so that area might be short too.<br />Duane Nashhttps://www.blogger.com/profile/14467779935085970909noreply@blogger.comtag:blogger.com,1999:blog-8161161431451849208.post-1505425696522768792015-10-19T03:29:15.252-07:002015-10-19T03:29:15.252-07:00Great artice=le as always, and the whole buoyancy ...Great artice=le as always, and the whole buoyancy thig makes a lot of sense for Spinosaurus. Do you think thick, buoyant skin would also be found on Baryonychines? I forgot how semi-aquatic they were, so I don't wether or not they would need such skin if they didn't spend that much time in the water.Iris-Katyayanihttps://www.blogger.com/profile/06188961246186305190noreply@blogger.comtag:blogger.com,1999:blog-8161161431451849208.post-54308808713578214542015-10-19T00:27:17.992-07:002015-10-19T00:27:17.992-07:00Yes but the same things keep ending up on far off ...Yes but the same things keep ending up on far off shore islands namely Elephants, Hippos and Deer.<br />And Elephants and Deer are known to be good swimmers; so perhaps Hippos under some circumstances are too.<br /><br />We need to experiment by floating Hippos of different ages and sizes in seawater to see if any of them are positively buoyant. :-)<br /><br />LeeB.<br /><br /><br />Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-8161161431451849208.post-45377203602830980792015-10-18T02:48:26.463-07:002015-10-18T02:48:26.463-07:00Thanks for comments
@LeeB concerning hippos getti...Thanks for comments<br /><br />@LeeB concerning hippos getting to Mediterranean islands/Madagascar. Shite I had wrote about those issues in an earlier draft that I lost when my computer went crazy thanks for bringing it up as it is a valid line of inquiry. <br /><br />Let me offer another hypothesis as to how hippos (and other megafauna) sometimes get to offshore isles. Highly rare but all too real mega environmental disturbances i.e. mega-tsunamis, 100, 1000, 10,000 year floods/typhoons/ storm surges. We know that these things happen for sure but they are so rare that they have mostly escaped observation by modern science. These perturbation can reshuffle the deck ecologically speaking. A pod of hippos that live near the ocean or in the ocean washed out to see. Clinging onto floating trees (a large baobob perhaps) and washing ashore.<br /><br />Such events may sound stunning but given a large enough time span they become real statistical probabilities.<br /><br />@lyuti I don't know about the skin being loose it really is thick though that we know for sure.Duane Nashhttps://www.blogger.com/profile/14467779935085970909noreply@blogger.comtag:blogger.com,1999:blog-8161161431451849208.post-74871004453735508802015-10-17T14:34:55.508-07:002015-10-17T14:34:55.508-07:00The skin, i meant ;).The skin, i meant ;).lyutihttps://www.blogger.com/profile/10594824751624532605noreply@blogger.comtag:blogger.com,1999:blog-8161161431451849208.post-45743433409175529402015-10-17T14:34:24.458-07:002015-10-17T14:34:24.458-07:00Those manaties also look fat because the sin is ve...Those manaties also look fat because the sin is very loose, don't they?. <br />I still have to connect the dots with the rest of your posts about these wonderful spinocritters, hope find the time this week. Awesome.lyutihttps://www.blogger.com/profile/10594824751624532605noreply@blogger.comtag:blogger.com,1999:blog-8161161431451849208.post-81082510272821996912015-10-15T23:49:50.944-07:002015-10-15T23:49:50.944-07:00I have heard that Hippos can't swim before but...I have heard that Hippos can't swim before but I wonder about this.<br />Firstly sea water is denser than fresh water so they may be closer to neutral buoyancy in it.<br />Hippos in Gabon are reported to travel up the coast surfing in the waves.<br /><br />And importantly, a number of Mediterranean islands (Crete, Malta, Cyprus) and also Madagascar had dwarf hippos on them; they apparently reached Madagascar over water at least twice.<br />As Madagascar and Cyprus at least have never been attached to the mainland for millions of years this suggested the hippos had to have swam or floated to them; as did the dwarf elephants also found on the Mediterranean islands.<br />Can hippos inflate some internal structure as a float when they have to?<br />Or are half grown hippos more buoyant than adults?<br /><br />LeeB.<br /> Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-8161161431451849208.post-48383767865002758842015-10-13T15:17:32.087-07:002015-10-13T15:17:32.087-07:00Thanks for comments
@Robert Haan Yeah I though of...Thanks for comments<br /><br />@Robert Haan Yeah I though of the mammalian/archosaur dilemma. A number of studies point to tetrapods of all groups showing remarkable convergence in form and function when evolving aquatic adaptations. Penguin, sea lion, and marine turtle underwater flight for instance. No idea on how much a thick skin of say 2-4 inches would add to weight. It could vary substantially I guess.. someone better at mathematics than myself should crunch some numbers!!<br /><br />@ Warren JB Yes I think the sail acted as ballast, display, prey corralling, and another idea I will go into next post.<br /><br />Duane Nashhttps://www.blogger.com/profile/14467779935085970909noreply@blogger.comtag:blogger.com,1999:blog-8161161431451849208.post-82239600543653323802015-10-13T10:28:22.567-07:002015-10-13T10:28:22.567-07:00Love the ideas you've presented here! I am de...Love the ideas you've presented here! I am definitely leaning towards the Mr. Big Spinosaurus Hypothesis as well.Anonymoushttps://www.blogger.com/profile/01656862236445590609noreply@blogger.comtag:blogger.com,1999:blog-8161161431451849208.post-49907450931876771762015-10-13T04:00:29.702-07:002015-10-13T04:00:29.702-07:00Oh yeah... that takes care of my AntSal withdrawal...Oh yeah... that takes care of my AntSal withdrawal symptoms...<br /><br />Does this suggest a possible role for the sail as a scaffold for - to use a technical term - a big wodge of thick skin, acting as both extra flotation and extra ballast? As opposed to a thin-skinned sail used *only* for display, or a fat hump.<br /><br />On Robert's point about mammalian divers, how do crocodylians compare?Warren JBhttps://www.blogger.com/profile/11743987856127631574noreply@blogger.comtag:blogger.com,1999:blog-8161161431451849208.post-87919916785079369362015-10-12T23:41:23.396-07:002015-10-12T23:41:23.396-07:00Interesting observations, its amazing how much of ...Interesting observations, its amazing how much of what we take as fact is based majorly on assumptions, indeed i never would have guessed that a thick hyde would have contributed such a great deal to the bulk of the animals you brought up as analogies , though a small question is at hand, i do note that all of the analogies you brought up fall under the order mamalia, would the same hold water (pun not intended) when applied archosaurian reptilimorph of the ilk of Spinosaurus. How much do you think it would have added to the mass of the animal in light of the current estimates ?Robert Haannoreply@blogger.com