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New takes on the Wealden Supergroup palaeobiota, part 1: Iguanodon, Neovenator, Eotyrannus and others

Source info:

Author: Mark Witton
Date: 2015-05-27 23:21:00
Blog: markwitton.com blog
URL: http://markwitton-com.blogspot.com/2015/05/new-takes-on-wealden-supergroup.html

Summary:

Regular readers will know that I'm prone to dabbling in palaeoart depicting the environments and animals of the Wealden Supergroup, the 18 million year stretch of Early Cretaceous time represented by mud-and sandstone deposits across the southern UK. Recently, I've been updating some existing Wealden work as well as producing some new stuff of other Wealden species. With no time to produce a new post of substance, here's a bumper 'picture of the day'-type post. Initially, I was going to chuck something like ten images on here, but time has run short and I'll have to split it in two.If you like anything here, remember that you can buy prints of them all from my shop (there's now a Wealden section, too), which is now also browsable from the comfort of Facebook. OK, enough preamble: into the Wealden once again...Iguanodon bernissartensis: thumb warsTwo Iguanodon bernissartensis, the quintessential Wealden iguanodont, decide to settle their differences, while members of their herd watch on.Poor old Iguanodon doesn't get the attention it used to, and a lot palaeoart we do see of it tends to focus on tried and tested behaviours: lots of standing about and eating, but not much else. In this new painting, I've attempted to show two big Iguanodon individuals settling an intra-specific dispute via use of thumb spikes. Long-term readers may recall that we've covered iguanodont thumb spikes before, and that I. bernissartensis has especially big ones. Here, they've been swinging their thumbs at each other's soft bits, causing deep, bloody wounds. This might seem extreme, but there are plenty of modern animals which take intraspecific fights to similarly gory levels - elephant seals were a key inspiration here. I imagine battling Iguanodon would look like an armed sumo-wrestling match, albeit with longer tails and less rice. Note that you can see the breath of several animals here: Wealden winters are not meant to be especially warm.Rebbachisaurids vs. Neovenator salerii reduxCarcharodontosaurian Neovenator salerii stalks a pair of rebbachisaurid sauropods, using darkness as cover.A while back I posted about dinosaur predation, noting that modern animal predator acts are often far less gladiatorial and epic than we might imagine. It's this slow, considered approach to predation which I'm attempting to show here, as the carcharodontosaur Neovenator stalks two rebbachisaurid sauropods in the dead of night. The idea is that the Neovenator has much better eyesight than the sauropods, who know they're in trouble, but can't really respond adequately. Note the rain: some recent models of Wealden palaeoclimates suggest it was wetter than previously modelled (albeit with very high evaporation rates for much of the year).Anteophthalmosuchus hooleyi vs. Hypsilophodon foxii, reduxLarge goniopholidid Anteophthalmosuchus hooleyi takes advantage of a flooding river to hunt two stranded Hypsilophodon foxii.Speaking of rain, we know that some parts of the Wealden were prone to flooding following particularly intense downpours. That's good news for animals adapted for powerful swimming, but less welcome to species which prefer dry land. Here, in this reworked painting, the large Wealden goniopholidid Anteophthalmosuchus hooleyi has found a stranded pair of adult and juvenile Hypsilophodon foxii, and is taking full advantage of the situation. Goniopholodids are a group of almost-crocodiles characterised by long forelimbs, interlocking scutes and overbitten jaws - you can read more about them here.Eotyrannus lengi: firestarter, redux Early tyrannosauroid Eotyrannus lengi stalks the edge of such a wildfire. What else does rain bring? Sometimes, lightning. When introduced to a parched Wealden landscape, lightning strikes caused short-lived canopy fires which, ultimately, created conditions ideal for fossil preservation. In this reworked painting, a fully-feathered tyrannosauroid Eotyrannus lengi is prowling the periphery of a Wealden canopy fire to grab any animals flushed out by the flames.The tiny wars of Wesserpeton evansae, redux Two Wesserpeton evansae get in each other's faces, because some animals are just jerks.OK, enough about Wealden weather. Here's a reworked version of two of the Wealden's tiniest tetrapods - indeed, some of the smallest fossil tetrapods of all - facing off in leaf litter. Recently named Wesserpeton evansae, these are albanerpetontids, very small amphibians which only died out a few million years ago. The 35 mm snout-vent length of these animals did nothing to temper their ferocity, and numerous jaws of Wesserpeton have healed fractures and breaks from intraspecific tussles. The animals in this picture are speaking the aggressive body language of modern salamanders as a prelude to their conflict. Two sauropods hang around in the background because, hey, it's called the Age of Dinosaurs for a reason. Some people have suggested this image borders on the trippy and surreal. Stay off the shrooms, kids. Rebbachisaurids and chumsLower Cretaceous rebbachisaurids and giant sauropod 'Angloposeidon' look for water in this desiccating Wealden lake.I do like rebbachisaurids, that group of sauropods who didn't get the memo about long necks. They're only represented by scrappy remains in the Wealden (a scapula) which is enough to tell us they were there, but not substantial enough to carry a name. Here, a few individuals are digging around a rapidly drying lake-bed to find a substantial source of water: digging elephants were the inspiration for this scene. In the background, probable brachiosaurid 'Angloposeidon' struts its stuff. It's meant to be walking particularly tall - I like the idea that fossil animals would carry themselves in different, characteristic ways, just as modern animals do. A pink gnathosaurine pterosaur has snuck into the foreground, just because. A lesser-seen Wealden scene: the Hastings Beds palaeobiotaFinally for now, here's one more new painting. This is a reconstruction of a swollen river representing part of the Hastings Beds, the oldest deposits of the Wealden, complete with local reptile fauna. The animals shown here are really poorly known: titanosaur 'Pelorosaurus' becklesii (bits of forelimb), possible carcharodontosaurian Becklespinax altispinax (three dorsal vertebrae), eucryptodiran turtle Hylaeochelys belli (a shell), and the possible azhdarchoid previously known as 'Palaeornis cliftii' (humerus). So yes, take the 'restorations' of these animals with an evaporite mine of salt: they're really just better known, fairly 'generic' representatives of groups represented by these Wealden taxa, air-dropped into a Wealden setting. Becklespinax is obviously modelled closely on Concavenator, as they seem to be pretty closely related and have a similar taste in dorsal ornamentation. I gave Becklespinax a more vertical anterior sail margin however, as indicated by the fossil. There's an article waiting to be written on palaeoart like this - should we even bother 'reconstructing' poorly known scenes and species? I clearly think we should, but we'll have to discuss the reasons why another time. I'm just now realising that there's a lot of confrontation in these images. Come back soon for a more placid, relaxed set of pictures in part 2...

Content analysis:

Stratigraphic context:

Recognized stratigraphic terms [n]:Cretaceous [1]
Lower Cretaceous [1]
Hastings Beds [2]
Agenames chronostratigraphy [rating]:Cretaceous [0.72]
Carboniferous [0.33]
Mesozoic [0.72]
Paleozoic [0.33]
Phanerozoic [0.81]
Lower Cretaceous [0.61]
Lower Mississippian [0.33]
Mississippian [0.33]

Geographic context:

LocationCountryLatitudeLongitude
Wealden DistrictGB50.94210.19564
The HastingsAU-26.3865153.09

Keywords:

aggressive body language, Albanerpetontids, animals, Anteophthalmosuchus hooleyi, anterior sail margin, armed sumo-wrestling match, big Iguanodon individuals, carcharodontosaurian Becklespinax altispinax, chumsLower Cretaceous rebbachisaurids, Early Cretaceous time, especially big ones, fully-feathered tyrannosauroid Eotyrannus, high evaporation rates, Hypsilophodon foxii, Iguanodon bernissartensis, iguanodont thumb spikes, juvenile Hypsilophodon foxii, large Wealden, lesser-seen Wealden scene, mm snout-vent length, modern animal predator, modern animals, mud-and sandstone deposits, Neovenator salerii, new painting, old Iguanodon, parched Wealden landscape, particularly intense downpours, pink gnathosaurine pterosaur, quintessential Wealden iguanodont, rebbachisaurid sauropods, reworked painting, salerii reduxCarcharodontosaurian Neovenator, short-lived canopy fires, similarly gory levels, smallest fossil tetrapods, stranded Hypsilophodon foxii.Speaking, thumb warsTwo Iguanodon, Wealden, Wealden canopy, Wealden lake.I, Wealden section, Wealden setting, Wealden species, Wealden Supergroup palaeobiota, Wealden taxa, Wealden weather, Wealden winters, Wealden work, Wesserpeton evansae

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