The study of trace fossils, such as tooth marks, can be used to provide information on feeding behavior (Jacobsen and Bromley 2009). Subsequent bone modification by the trace makers on the corpses also can be studied to determine feeding methods and jaw mechanics (Gignac and Erickson 2012). Morphology of the traces can be quantified to further discern these mechanisms by comparing potential modern and extinct animal trace-makers (Roland and Bromley 2009). In this paper, the ichnological terminology of tooth trace kind and category is followed as reported by Tanke and Currie (1998), Pirrone et al. (2014), and Jacobsen and Bromley (2009). Interpretation of the causes of these tooth traces offers information on social and environmental causes (Lovell, 1997). Additionally, the bone modifications made by animals while feeding also leave tell-tale traces on the bones of the prey items (Johnson 1989) and can be used to interpret behavior.

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Nearly all T.rex are brown. Peter is an incredibly rare and visually stunning obisidian black color.

Tyrannosaurus rex, as the top predator in the Lancian ecosystem, has been suggested to have had the ability to crush large bones in a single bite (Gignac and Erickson 2012). In this report we argue that trace fossils and bone modification can be used to unravel taphonomical events and lend insight into life histories of Tyrannosaurus rex, especially of the individual, ‘Peter’.

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Sharing the science

We’re pleased to be able to share Preliminary Scientific Reports to help visitors who come to see these incredible T. rex understand more about them.

These reports are prepared by two of the world’s top therapod paleontologists, Dr David Burnham (University of Kansas Biodiversity Institute and Natural History Museum) and Dr John Nudds (Department of Earth and Environmental Sciences, University of Manchester), who have studied both Peter and Barbara in their university laboratories for many months. Their research has identified the unique pathologies of each specimen, such as the injury to Barbara’s leg and the marks on Peter’s leg. As these reports are preliminary, they’re not peer-reviewed yet.

It’s not standard practice for a museum to share this much information when a specimen is being exhibited for the first time, but with the benefactor’s agreement we’re keen to share the initial findings, to enhance the learning experiences that having these two specimens in our Museum provides for the people of Aotearoa New Zealand.

Updates to the Preliminary Scientific Reports will be an ongoing process and will most likely span decades, rather than years.