Dinosaurs on the Isle of Wight

[Ben Creisler <bcreisler@gmail.com>]

Ben Creisler
bcreisler@gmail.com

In the new special issue of Biological Journal of the Linnean Society:



H. S. Torrens (2014)
The Isle of Wight and its crucial role in the ‘invention’ of dinosaurs.
Biological Journal of the Linnean Society 113 (3): 664–676
Special Issue: Celebrating Dinosaur Island
DOI: 10.1111/bij.12341
http://onlinelibrary.wiley.com/doi/10.1111/bij.12341/abstract

Dinosaurs were 'invented' in April 1842. Any history, before this,
must separate periods of pre-history. The first covers the period
before 1824 (when the first dinosaur genus Megalosaurus was
described). Here the Isle of Wight discloses a forgotten pioneer in
natural history, the stone mason/sculptor James Hay (c. 1748–1821) who
may well have included, by 1818, such dino-to-be material in his
remarkable Portsmouth museum. This was described on his death as ‘the
best private collection in the kingdom’. Sadly, his material is lost,
and no accurate diagnosis is possible. The second period extends from
1824 to 1842. The significant figure here is the Russia and East
Indies merchant James Vine (1774–1837), who first revealed how
Iguanodon bones occurred in abundance in the Island's south-west
coastal outcrops. One, between September 1841 and April 1842, revealed
to Richard Owen his long-sought fossil sacrum of an Iguanodon. This
was in the private London museum of the political radical W. D. Saull
(1783–1855). The discovery of this single fossil enabled Owen to
‘invent’ dinosaurs. He later wrote of this historic specimen how ‘the
characters of the order Dinosauria were mainly founded on this
specimen’. So, in a real sense, the Isle of Wight is the birthplace of
Dinosaurs.

***
Jeremy A. F. Lockwood, Martin G. Lockley and Stuart Pond (2014)
A review of footprints from the Wessex Formation (Wealden Group, Lower
Cretaceous) at Hanover Point, the Isle of Wight, southern England.
Biological Journal of the Linnean Society 113 (3): 707–720
Special Issue: Celebrating Dinosaur Island
 DOI: 10.1111/bij.12349
http://onlinelibrary.wiley.com/doi/10.1111/bij.12349/abstract

Hanover Point on the Isle of Wight, England, is a Lower Cretaceous
(Barremian) site yielding a large number of dinosaur footprints from
the Wessex Formation. These footprints, hitherto often referred to as
‘Iguanodon’ tracks, have generated interest and speculation since the
beginning of the Victorian era. Today, Hanover Point largely yields
sandstone casts (convex hyporeliefs) of footprints but also includes
some impressions (concave epireliefs), a few of which form short
trackways. The majority belongs to large ornithopods, many with foot
lengths in excess of 50 cm. Theropods and the occasional thyreophoran
track are also represented. The site represents the Wessex Formation
within the Wealden Group and can be described ichnologically as a
category 3a deposit. Most of the large ornithopod footprints have a
distinctive quadripartite morphology and are best assigned to the
ichnogenus Caririchnium or in some cases Amblydactylus. Few are
morphologically compatible with Iguanodontipus which was described
from pre-Wealden deposits and appears to be little represented in the
Wealden ichnofaunas.

***

Martin G. Lockley, Lida Xing, Jeremy A. F. Lockwood and Stuart Pond (2014)
A review of large Cretaceous ornithopod tracks, with special reference
to their ichnotaxonomy.
Biological Journal of the Linnean Society 113 (3): 721–736
Special Issue: Celebrating Dinosaur Island
DOI: 10.1111/bij.12294
http://onlinelibrary.wiley.com/doi/10.1111/bij.12294/abstract

Trackways of ornithopods are well-known from the Lower Cretaceous of
Europe, North America, and East Asia. For historical reasons, most
large ornithopod footprints are associated with the genus Iguanodon
or, more generally, with the family Iguanodontidae. Moreover, this
general category of footprints is considered to be sufficiently
dominant at this time as to characterize a global Early Cretaceous
biochron. However, six valid ornithopod ichnogenera have been named
from the Cretaceous, including several that are represented by
multiple ichnospecies: these are Amblydactylus (two ichnospecies);
Caririchnium (four ichnospecies); Iguanodontipus, Ornithopodichnus
originally named from Lower Cretaceous deposits and Hadrosauropodus
(two ichnospecies); and Jiayinosauropus based on Upper Cretaceous
tracks. It has recently been suggested that ornithopod ichnotaxonomy
is oversplit and that Caririchnium is a senior subjective synonym of
Hadrosauropodus and Amblydactylus is a senior subjective synonym of
Iguanodontipus. Although it is agreed that many ornithopod tracks are
difficult to differentiate, this proposed synonymy is questionable
because it was not based on a detailed study of the holotypes, and did
not consider all valid ornithopod ichnotaxa or the variation reported
within the six named ichnogenera and 11 named ichnospecies reviewed
here. We therefore emphasize the need to base comparisons between
ichnotaxa on type material, and not on selected referred material. It
is concluded that there is considerable variation in the morphology of
the holotypes, as well as variation in size and quality of the samples
and the mode of preservation. Conversely, there is considerable
overlap in morphology among other tracks that have been informally
attributed to these ichnotaxa. These factors make it difficult to
synonymize any of the existing ichnotaxa without detailed revision of
the samples from which the type material originates. Nevertheless, a
review of the type material of all ichnotaxa is presented as a basis
for further discussion and, as a first step, the ichnofamily
Iguanodontipodidae is proposed to accommodate Amblydactylus,
Caririchnium and Iguanodontipus,

***
Stuart Pond, Martin G. Lockley, Jeremy A. F. Lockwood, Brent H.
Breithaupt and Neffra A. Matthews (2014)
Tracking Dinosaurs on the Isle of Wight: a review of tracks, sites,
and current research.
Biological Journal of the Linnean Society 113 (3): 737–757
Special Issue: Celebrating Dinosaur Island
DOI: 10.1111/bij.12340
http://onlinelibrary.wiley.com/doi/10.1111/bij.12340/abstract


The Wealden exposures on the Isle of Wight have long been noted for
their dinosaur footprints and trackways and represent a unique
ichnological resource. However, with a few notable exceptions, these
ichnites remain largely unstudied and documentation has been sporadic
and often concentrated on a few particular sites. Thus, their context
within the Lower Cretaceous is poorly understood. The vertebrate
ichnological record of the Wessex Sub-basin is currently being
re-assessed. We review the main sites containing dinosaur footprints
on the Isle of Wight. We also look at previously-known sites, and
present new research using techniques such as photogrammetry to
accurately record, preserve, and distribute ichnological data,
especially data recorded in the dynamic foreshore and cliff
environments, where many trace fossils are frequently lost as a result
of human activity, weathering, erosion, and changing marine dynamics.
Although the ichnoassemblages of the island's Wealden facies are
dominated by ornithopod tracks including Caririchnium and
Amblydactylus, we also report the first occurrence of the
ankylosaurian track Tetrapodosaurus in both the Wessex and Vectis
Formations, alongside the previously reported stegosaurian Deltapodus,
as well as the occurrence of tracks left by saurichian tracemakers.
****

Trevor Price (2014)
New dinosaur footprints exposed in rocks of the Wessex Formation,
Lower Cretaceous, at Sandown, Isle of Wight, southern England.
Biological Journal of the Linnean Society 113 (3): 758–769
Special Issue: Celebrating Dinosaur Island
DOI: 10.1111/bij.12365
http://onlinelibrary.wiley.com/doi/10.1111/bij.12365/abstract

During February 2007, storm waves removed sufficient sand from the
foreshore at Sandown beach on the Isle of Wight to expose a number of
Lower Cretaceous interbedded fluvial sand sheets and floodplain
mudstones from the upper part of the Wessex Formation terrestrial
sequence. The sand bodies have been described before, and exhibit a
number of water generated ripple marks, as well as bioturbation by
burrowing organisms. These sand bodies and a fossiliferous limestone
have resulted in the area being designated as a Regionally Important
Geological/Geomorphological Site. The mudstones show colour mottling
as a result of pedogenic alteration in changing aerobic/anaerobic
conditions. From February until the end of May 2007 sufficient
exposure of the bedrock on the foreshore occurred to allow
identification of a number of dinosaur footprints. Tridactyl and
polydactyl prints with a range of sizes were clearly visible with
possible ornithopod, theropod, sauropod, and ankylosaur origins.
Within the intervening mudstones, preservation of the footprints takes
the form of grey–blue infills in red mud, and brown silty infills in
red mud (convex hyporeliefs), as well as occasional raised gritty
footprint casts. On the sandstone units, the preservation is in the
form of raised sandy casts. The greatest variety in terms of size and
type are in the mudstone units on the seaward side of the Isle of
Wight Zoo (The Granite Fort). These prints are from an area that does
not appear to have been previously reported but which requires further
investigation.