• Category Archives Uncategorized
  • Site maintenance update

    This should be what people see when they go to make a comment now. If this changes please let me know.

    This is a short status update for the site. When I switched up the theme for the site back in 2014, I did so with the intent of making it more interaction friendly. That included threaded comments and the ability to subscribe to those comments. A couple of days ago I noticed that both the post subscription and comment subscription options had stopped working (the latter had completely disappeared). I dove into the backend to see what was causing the trouble and I think I’ve been able to fix it. Now when you go to a comment or reply there should be a box at the bottom that lets you choose to subscribe to the comment thread and be notified via e-mail if you would like to get updates.

    The other thing I noticed is that I was getting a lot of e-mail bounces for confirmation e-mails on subscriptions. I changed the e-mail for the site to a more Reptipage-specific e-mail, so that should no longer happen anymore.

    NOTE: If you do hit subscribe but still don’t see any confirmation e-mail come through (it should be near instantaneous), check your spam folder. I’ve found that there are quite a few e-mail providers that are autoblocking these confirmation e-mails. If that’s the case, just whitelist the e-mail sent from the site and that should fix the problem.


  • The return of the scaly T. rex to modern paleo-art

    Tyrannosaurus rex walking towards camera. Art by John Sibbick.

    [NOTE: Post has been updated to include a section on scale size]

    This has certainly been an interesting year. Two papers dropped in the past three months that have put the brakes on a recent trend in paleo-art. That trend? Why the feather-coated T. rex of course.

    First, in March, we saw the release of a paper detailing a new species of Daspletosaurus and its relationship to D. torosus.

    Carr, T.D., Varricchio, D.J., Sedlmayr, J.C., Roberts, E.M., Moore, J.R. 2017. New Tyrannosaur with Evidence for Anagenesis and Crocodile-Like Facial Sensory System. Scientific Reports. 7(44942):1–11.

    In this paper, Carr et al. argue for the designation of a new Daspletosaurus species, D. horneri. The authors argue, based on skull shape and chronostratigraphic position, that D. horneri was the direct ancestor to D. torosus. I thought that the authors put forth a compelling argument for this anagenic event and backed up their position well. Interestingly, this part of the paper should have been the most controversial. As anyone who has read anything from Horner and Scanella over the past eight years can attest, arguing for a direct ancestor-descendant relationship for dinosaurs is difficult to do and even harder to win over others in the field. So it is somewhat surprising to see a case for anagenesis in Daspletosaurus taken so well by the palontological community. All the more so given that it involves a tyrannosaur, the poster children for “cool guy” dinosaurs.

    Instead, the most controversial part of the paper wound up being their soft-tissue reconstruction of the face for D. horneri. The author responsible for the soft-tissue reconstruction was Jayc Sedlmayr of Louisiana State University. Sedlmayr did his doctorate on osteological correlates for vasculature in extant archosaurs (birds & crocs). He is the seminal alumnus of the WitmerLab and thus is well within his wheelhouse for this type of soft-tissue reconstruction. Sedlmayr borrowed heavily from the work of another WitmerLab alumnus, Tobin Hieronymus, whose PhD work involved osteological correlates for integument on the skulls of animals. Although the skin is often well away from the underlying bones on most of the body, there are exceptions when it comes to the skull. There, areas that are not heavily muscled, tend to show intimate connections between the skin and the underlying bone. Hieronymus used these connections to determine how different integumentary appendages (scales, hair, feathers) affect the underlying bone (Hieronymus & Witmer 2007; Hieronymus et al. 2009). The authors found that the surface texture along the skull of D. horneri was “hummocky”. That is, it was covered in lots of closely packed ridges. According to Hieronymus & Witmer (2007), this texture correlates to scales as the overlying integumentary appendage. Thus, according to the authors, D. horneri had a scaly face (this is grossly oversimplified as the authors were able to piece together a variety of different integument variants along the skull, but you get the idea).

    Scaly tyrannosaur cannonball one had been shot.

    Then two weeks ago, we saw the release of another paper on tyrannosaur integument. However, unlike the previous paper, this one was specifically dedicated to integumentary types in tyrannosaurids.

    Bell, P.R., Campione, N.E., Persons, W.S., Currie, P.J., Larson, P.L., Tanke, D.H., Bakker, R.T. 2017. Tyrannosauroid Integument Reveals Conflicting Patterns of Gigantism and Feather Evolution. Biology Letters. 13:20170092

    In this paper, the authors set out to survey all known instances of “skin” impressions for tyrannosaurids. Their list of taxa included Albertosaurus, Tarbosaurus, Daspletosaurus, and Gorgosaurus. Their results pretty definitively indicated that scales were the predominant integumentary appendage on tyrannosaurids. The authors then went on to speculate why that would be if earlier tyrannosauroids had filamentous integument. They performed an ancestral character state reconstruction based on Parsimony and Bayesian-based trees from Brussatte and Carr 2016. Their results found that filaments came out strongly as the ancestral character for tyrannosauroids, but by no later than Tyrannosauridae proper, a reversion to scales had taken effect. The authors attributed this to body size evolution. Namely, larger tyrannosauroids reverted to scales over protofeathers.

    Cannonball number 2 had just been shot.

    Continue reading  Post ID 1804


  • New study shreds the dinosaur family tree (and exposes double-standards in Phylogenetic Nomenclature)

    Figurative illustration of the new phylogeny by Baron et al. 2017

    Most folks who visit my site by now have seen the big dinosaur news that has hit the interwebs. A new study from Matthew Baron, David Norman and Paul Barrett from University of Cambridge and the Natural History Museum of London, has seriously challenged the classic interpretation of dinosaur phylogeny.

    Baron, M.G., Norman, D.B., Barrett, P.M. 2017. A New Hypothesis of Dinosaur Relationships and Early Dinosaur Evolution. Nature. 543:501–512.

    Classical dinosaur phylogenetics

    Although originally thought of as two unrelated branches of Reptilia that grew to immense size during the Mesozoic (e.g., Charig et al. 1965), for the last 43 years the group, Dinosauria, has been considered monophyletic (i.e., sharing a single origin) with the subgroups, Saurischia & Ornithischia, forming the first major branches within the group (Bakker et al. 1974). Saurischians, or “reptile hips” were aligned together by their similar hip shapes, skull characters (e.g., open antorbital fenestrae), and inferred soft tissues (e.g., air sacs). Ornithischians, or “bird hips” shared a hip structure that was superficially similar to that of birds, with a pubis that pointed caudally rather than rostrally, along with a variety of unique skull characters such as a neomorphic bone known as the predentary.

    Study after study showed that this relationship was sound, and so it stayed that way. The problem with getting the same answer over and over again is that one eventually stops questioning it. Consistent results become  common knowledge, and may even graduate to dogma. That’s not so bad if that common knowledge is true, but all too often many of these “obvious” cases wind up being just so stories upon closer inspection.

    Continue reading  Post ID 1804


  • Modern-day paleo myths: Dinosaurs as lizards

    Paleomyths

    In this day and age there are no shortage of books, websites, and videos dedicated to debunking classic paleo myths. The majority of this mythbusting focuses on myths about dinosaurs. As the poster children for paleontology, this isn’t that surprising. With so many takes on this subject it comes as no surprise that all of the classic dinosaur myths have long since been debunked, such as dinosaurs as low-energy tail draggers, walking around like Godzilla, being evolutionary failures, inferiority to mammals, being pee brained monsters, etc.

    However, as quickly as these classic dinosaur myths have been eradicated, new ones have come and taken their place. These myths/misconceptions are routinely cited today without any question despite being just as erroneous as the myths that preceded them.

    This is the start of a new series I want to cover on the site: dispelling modern myths in vertebrate paleontology. Given the bent of my website, these myths/misconceptions will largely stay focused on reptile-related animals, though I am open to taking the occasional foray into other animal groups if the myths are egregious enough (which is to say that suggestions are welcomed).

    The seminal installment for this series is one that I see mentioned time and again:

    “Dinosaurs were once thought of as big lizards.”

    Continue reading  Post ID 1804


  • T-U-R-T-L-E Power Part 4: The little-known paleobiology of the world’s largest tortoise

    Megalochelys_atlas
    Megalochelys atlas skeleton on display at the AMNH. Photo by Clair Houck (Wikipedia)

    Today, the largest turtle alive is easily the leatherback turtle (Dermochelys coriacea), at a whopping 916 kg (2,015 lbs, Eckert & Luginbuhl 1988). On land, the largest turtle goes to Chelonoidis nigra (Galápagos tortoise) which has been reliably recorded as reaching up to 417 kg (919 lbs) in weight (Guinness World Records). However, both extant turtles are dwarfed in size by an immense land tortoise that lived as little as 1.7 million years ago, in the Pleistocene.

    Continue reading  Post ID 1804


  • Tegus get hot and bothered during the breeding season

    Infrared image of two tegus, courtesy of the Tattersall Lab.
    Infrared image of two tegus, courtesy of the Tattersall Lab.

    I haven’t done one of these short, newsy posts in a while. However, I felt this one warranted the attention.

    Announced today, a new paper from Glen Tattersall and colleagues (open access):

    Tattersall, G.J., Leite, C.A., Sanders, C.E., Cadena, V., Andrade, D.V., Abe, A.S., Milsom, W.K. 2016. Seasonal Reproductive Endothermy in Tegu Lizards. Sci. Adv. 2:e1500951.

    In another example of slow-cooked science, this paper was the culmination of over three years worth of work collecting data on tegus. For the study, the authors looked at adult black and white tegus (Salvatore merianae). Tegus are an interesting group of lizards. They are the largest members of the family Teiidae and are often referred to as the monitor lizards of the new world, due to their convergent lifestyles (highly predaceous, active foragers). Besides their varanid-like demeanor, tegus are also known for their enormous jowls, especially in the males. The jowls hold the pterygoideus muscles, the big jaw snappers, which have been shown to increase in size for males during the breeding season (Naretto et al. 2014). As reptiles, tegus have been assumed to follow the standard ectothermic lifestyle of requiring external sources of heat to warm their bodies and maintain stable body temperatures. Looking at the natural history of the animals, tegus appear to fit the mold pretty well. They have distinctive winter and summer activity levels. In the summer, the animals regularly maintained body temperatures of 32–35°C, and in the winter they let their body temperatures drop to the temperature of their burrows (15–20°C). This is all fine and good for a bradymetabolic, ectothermic lizard, but when the researchers tracked body temperatures over time they discovered something completely unexpected.

    Continue reading  Post ID 1804


  • Jurassic World Review

    It's here!
    It’s here!

    I figured if I was going to do a Jurassic World-related post on Stegosaurus I might as well follow it up with a review for the film. I grossly underestimated the draw of dinosaurs to the cinema. Despite 22 years of Jurassic Park, Walking with Dinosaurs (BBC version, not the Disney thing), and so on, people never seem to be burnt out on dinosaurs. That’s good news for paleontology (yay!), and also for movies seeing as how Jurassic World just raked in a record-breaking $208.8 million domestic in its opening weekend.

    So what did I think?  In short: I liked it and found it to be a worthy successor to the franchise.

    If you’d like the longer, spoiler-ridden version click on the jump.
    Continue reading  Post ID 1804


  • Jurassic World and the case of the droopy-tailed Stegosaurus

    As I write this the US premiere of Jurassic World is just around the corner. I had gone back and forth regarding this post given that we currently know very little about the film and as such the interpretations written about here and elsewhere may well be pointless by the time the film premieres.

    Ultimately I decided to post this anyway since the overall thrust of the article should remain true regardless of how the film pans out.


    Now there has been a lot of buzz around Jurassic World since it was first announced last year. The buzz has been mixed, but fairly positive. I suspect this was, in part, because everyone was happy to hear that the godawful military dinosaur idea was shelved in favour of a more “traditional” JP franchise storyline. Nonetheless the movie has still drawn its fair share of detractors, including myself. Most of the people who are unhappy with the film are either paleontologists, or hardcore dinophiles. Many of the problems leveled at the film have to do with the portrayal of the extinct animals. The problems are actually myriad ranging from pterosaurs capable of picking up humans using grasping feet, mosasaurs that are twice the size of blue whales, sauropods covered in elephant skin rather than scales (a problem not unique to Jurassic World), everything about Velociraptor, and of course Indominus rex.  My biggest beef with the film is that the dinosaurs are not being shown as dinosaurs so much as monsters. However, after The Lost World: Jurassic Park came out it became pretty evident that Spielberg’s original vision of portraying dinosaurs as animals had been shelved in favour of the more entertainment-friendly movie monster approach. However, for what seems like a majority of the detractors, the biggest gripe with the film has to do with a lack of  feathers on pretty much all the dinosaurs. This seems to be a common theme these days with a particularly vocal group of dinophiles and paleontologists strongly pushing for the feathering of every dinosaur in sight and insisting that all media that portrays scaly (erroneously called: “naked”) dinosaurs is inaccurate. Never mind the fact that a feathered, pack-hunting, 2 meter tall Velociraptor mongoliensis is still every bit as inaccurate as a scaly one.

    Anyway, I digress. Dealing with the overwhelming amount of internet drama surrounding Jurassic World (and the media depiction of dinosaurs in general) is a topic for another day. My reason for writing this post is centered around one particular criticism that popped up a few weeks ago.

    Continue reading  Post ID 1804


  • Out of stasis once more

    Weyland-Yutani stasis pod concept art.
    Weyland-Yutani stasis pod concept art.

    Visitors to the site may have noticed that it has been stuck in archive mode for the past however many months. This only recently came to my attention when I had noticed a lack of update nags from WordPress. Further investigation revealed that comments were no longer going through, nor were new posts. Given the global lockdown of the site I suspected that I was either hacked (again!) or that there was a database issue. A quick scan from Sucuri eliminated the first option (or at least made it less likely), which led me to check the database.

     

    Lo and behold I found that the Reptipage database is currently holding at  approximately 150 MB. Unfortunately,  my current webhost (1and1.com) had a hard limit of 100 MB for databases at my current hosting level. I say “had” because they have since bumped database sizes up to 1GB. The problem was that any old databases currently in use were still subjected to this hard limit. I was 50MB over the hard limit so the MYSQL database was locked down. Hence the lack of updates, comments, posts, etc. I would have caught this sooner, but the demands of my current job have caused the site to get backburnered.

    The site is now on a new database that has more legroom to it and I’m now aware of this looming problem (the DB isn’t 1GB now, but it will be in the future). I’m looking into spreading the Reptipage across a few databases using the hyperDB plugin. We’ll see where it goes.

     

    Also, there has been a bit of a lull in my current workflow that has freed up some time that I intend to devote to writing again. Between T. rex autopsy and Jurassic World (both coming out in a few weeks) there is no shortage of excitement, controversy and overall butthurt on the internet that I can talk about. There has also been a bevy of cool new things regarding extant reptiles which I intend to get back to covering.

    So that is the current status of things. I have some posts in the hopper that should be coming out shortly. I apologize for having the site in archive mode for so long.

    Time to get back to business.

    ~ Jura

     


  • Site update

    I finally got around to making the site more social-media friendly. You should now have the ability to easily share posts on all the major social media services.

    I also fixed a bug in the CSS that kept the font colour for the author fill-in fields black. My apologies to everyone who has been commenting in spite of the problem. I was not aware of it until recently. I also wasn’t aware that you could not subscribe to comments, so I fixed that problem too. You can now subscribe to posts with or without commenting. You can also receive notifications for just replies to your comments if that is what you prefer.

    Hopefully the site is a bit more user friendly now. Let me know if anything else is broken.

    [Update: I also updated the theme from (which I had not changed since 2007). The old theme would not allow for threaded commenting, which can be extremely frustrating when there are extensive comments. The new theme allows for this and a host of other things too. Now I just need to fix about a dozen small little bugs and things should be good.]

    ~Jura