The Dinosaur Dreaming 2017 field report was presented at the annual Report Day, held at Museum Victoria in Nicholson Street Melbourne, on Saturday 16th December 2017. The presentation was held much later than usual due to head researcher Dr. Tom Rich being overseas until early December.

The 2017 report was dedicated to David Pickering who passed away on December 24th 2016 after a serious car accident. Dave was Museum Victoria’s Collections Manager for Vertebrate Palaeontology, Dinosaur Dreaming co-coordinator, dig leader of the Eric the Red West field trips and a dear friend to many people, including myself. In Tom Rich's words Dave was “a person who, in a myriad of ways, bolstered the morale of the whole crew. We all observed his willingness to explain the intricacies of fossil collecting to new people and his wry sense of humour. Dave has left an indelible mark – not only on the many palaeontologists across the country, and indeed the world, that he has encouraged, mentored and supported”.

Dave’s presence was sorely missed at the 2017 Eric the Red West field trip, but a number of experienced crew members stepped up to fill the gap to keep the dig going as Dave would have wanted them to.

A number of interesting articles are included in the annual report, some of which will be covered in future updates. Tom Rich’s report included mention of a discovery that occurred 16 years ago during the 2001 Dinosaur Dreaming field season at the Flat Rocks site, near Inverloch. It was the discovery of the smallest mammal jaw ever found at the Flat Rocks site and indeed possibly one of the smallest mammals that ever lived.

Excerpt from Tom's report

“I started to write a manuscript on the three fragmentary mammal jaws collected more than a decade ago (collectively referred to informally as Gerry’s Jaw because the first of them was found by Gerry Kool at Flat Rocks in 2001), and found that one of them is, in fact, Bishops. The other two specimens belong to the same new species and genus that will be named in honour of Gerry. It is much smaller than Ausktribosphenos and Bishops (see front cover) and rivals in size what may be the smallest mammal that ever lived, known from the Early Eocene of Wyoming, Batodonoides vanhouteni.“

Tom is hopeful that the paper announcing Gerry’s jaw to the world will be out later this year. We will announce the publication as soon as it is available.

Tom also mentioned the work carried out by American histologist Holly Woodward. Holly visited Australia a couple of years ago and while she was at Museum Victoria she analysed the histology (microcellular structure) of 17 limb bones from some of the small Victorian ornithopods. Her paper on the results of her analysis was published in January this year:

H.N. Woodward, T.H. Rich and P. Vickers-Rich 2018. The bone microstructure of polar “hypsilophodontid” dinosaurs from Victoria, Australia. Scientific Reports (2018) 8:1162 | DOI:10.1038/s41598-018-19362-6

Below is the abstract from Holly’s paper:

High-latitude (i.e. “polar”) Mesozoic fauna endured months of twilight and relatively low mean annual temperatures. Yet non-avian dinosaurs flourished in this taxing environment. Fossils of basal ornithopod dinosaurs (“hypsilophodontids”) are common in the Early Cretaceous high-latitude sediments of Victoria, Australia, and four taxa have been described; although their ontogenetic histories are largely unexplored. In the present study, eighteen tibiae and femora were utilized in the first multi-specimen ontogenetic histological analysis of Australian polar hypsilophodontids. The sample consists of eleven individuals from the Flat Rocks locality (Late Valanginian or Barremian), and five from the Dinosaur Cove locality (Albian). In both groups, growth was most rapid during the first three years, and skeletal maturity occurred between five and seven years. There is a weak asymptotic trend in a plot of growth mark count versus femur length, with considerable individual variation. Histology suggests two genera are present within the Dinosaur Cove sample, but bone microstructure alone could not distinguish genera within the Flat Rocks sample, or across the two geologically separate (~ 26Ma) localities. Additional histologic sampling, combined with morphological analyses, may facilitate further differentiation between ontogenetic, individual, and species variation.

I recommend that readers check out this paper as it covers small ornithopods from both the Otway and Strzelecki Ranges.

Next update will cover the “Big discovery” made in the last days of the 2017 Eric the Red West field trip. So stay tuned.

Images:
Cover of the 2017 Dinosaur Dreaming Annual Report, showing the size of “Gerry’s jaw” to a normal sized Ausktribosphenid mammal jaw. Image courtesy of Wendy White.

Figure 1 from Holly Woodward’s paper on the Victorian ornithopods.

DD 2017 annual report cover

Fig 1 from Holly Woodward's report