Curator Wayne Gerdtz with Jurassic poo. Image Benjamin Healley, Museum Victoria.

The lump looks small and unassuming. It has a rough texture and is surprisingly heavy for its size. This small pink and grey rock holds an intriguing secret. It is a 150 million year old sauropod dinosaur poo – fossilised and preserved as a record of life in a very different time.

Imagine standing in a lush Jurassic forest in what is present day Utah, USA.
The ground vibrates with thundering footfalls. It is a 25 tonne sauropod coming to feed. Its giant neck and small head reach into the dense vegetation to tear off some leaves. The mouthful of leaves travels down its long neck to its roomy stomach. Fermentation chambers filled with bacteria in its guts help break down the plant fibres and extract the nutrients. A soft lump of poo falls onto a bit of swampy ground, where it is preserved and fossilised – turned into stone. It is buried and remains hidden for 150 million years until someone digs it up. We acquire it for the museum.
 
Fossilised poo – or ‘coprolites’ – were unveiled at Melbourne Museum today in preparation for installation in the Dinosaur Walk, opening on April 3 at Melbourne Museum. A coprolite will be on open display in the new exhibition, enabling visitors to touch it for themselves.

How do we know it is dinosaur poo? It comes from a rock layer known as the Morrison formation, which is the right age and contains many fossils of Late Jurassic dinosaurs. It is the ‘right’ size and shape. It is similar to other lumps which have been analysed and have been found to have plant remains in them. The process involves looking at thin sections of the rock under a microscope, where traces of plants can be seen. We cannot be 100% sure our lump is fossilised dinosaur poo, but the evidence suggests it is highly likely.

Is it rare? Fossils of dinosaur bones are quite rare, but fossils of soft parts like skin, muscle or traces like poo are even rarer. The conditions to preserve a soft lump are unusual, so coprolites are rare.

Featherheads Ptilotus macrocephalus, Photographer: Kate Phillips, Source: Museum Victoria

I was not expecting to see a dead dog, three dead armchairs and nine dead mattresses when searching for native grassland plants. Tracey-Ann Hooley and I went out this afternoon in search of the best looking native grassland in Melbourne for close-up photography.

Perhaps I shouldn’t have been surprised. After all, native grasslands are viewed as dumping grounds or empty space by many people. Once they become weedy and full of rubbish, it is even harder to appreciate them. Even I, who was trying hard to find and photograph the delicate and diverse plants, could not help being distracted by the piles of rubbish and general air of desolation.

Needless to say, that grassland did not get our vote for the ‘Melbourne Grassland Idol’. However, I did have genuine moment of appreciation as a gusty wind blew through the Tussock grass. The noise was delightful and the grass showed subtle shades of pink, purple yellow and green as the wind rippled through it. I could actually see the wind change direction, ebb and flow.

Other grasslands in western Melbourne are much better cared for. We visited several with a diversity of native grasses and other native plants many which are in flower now. It is generally a case of getting down on hands and knees to get a good view. My favourite flower would have to be the featherheads Ptilotus macrocephalus which feel downy soft.

So there are good grasslands out there – not that many. They are small and faragmented. They are surrounded by houses, roads and industry. But they are still there, and blooming. 

Trying to visualise ane million years I a created a document with one million dots. Here is one page – it  takes 96 pages like this to hold one million dots.  

When we did some evaluation of ideas for exhibitions and talked about dinosaurs, only one out of the forty adults we interviewed said they would like to see how the dinosaurs and cavemen lived together (think ‘The Flintstones’), but that one was enough to remind me that not everyone has a scientific appreciation of the sequence of life on earth, let alone the mind-bogglingly long time periods over which happened. I’m only just getting comfortable with the idea of a million years myself. 

To get a mental image of one million, I created a word document with one million dots on it. I made the dots as small as possible and they covered the page – you can only just see them as separate dots. The document is 96 pages long, so I’ve only ever printed out one page. It was an interesting exercise! 

600 million years ago  (that is 600 000 000) is the time span for one of the new exhibitions. We start with the dawn of animal life (i.e. multicellular organisms) and end with the relative recent megafauna which became extinct a mere 40 000 years ago, or 0.04 million years ago. While I still struggle with these time spans, the palaeontologists and geologists at the museum think effortlessly in millions of years. 

I remember watching a documentary about Thylacaleo, or ‘marsupial lion’. A perfectly preserved 1 million-year-old skeleton was found in a cave in the Nullarbor. The animal probably fell into the cave and died. Then gradually dried out and remained undisturbed for one million years to be discovered by some intrepid cavers a few years ago. Just lying there for one million years …quite astounding really. But to my geologist friends here at the museum, that isn’t old, a mere million years – hardly any time at all… 

Fossilised dinosaur bones with comb for scale

Today I have been writing words that will be part of a new exhibition. It’s a new exhibition with an old theme – dinosaurs and other pre-historic life.  According to my text there is going to be a fossil hairdresser in it. Well it isn’t actually a fossil hairdresser, that’s just what spell check came up with when I typed Hadrosaur. We have this fossil of a Hadrosaur (duck–billed dinosaur) – still embedded in a chunk of rock which came all the way from Alberta, Canada. At the museum it is affectionately called the headless hadrosaur because there is no skull fossil. It does however have imprints of dinosaur skin, and when you think of it, 70 million year old skin is pretty impressive (probably in need of a beauty therapist rather than a hairdresser).  

The collection manager here at the museum is going to look closely around the fossil in the hope of finding some more skin. There are stories of similar fossils where the people preparing them (cleaning away the rock and just leaving the fossil), failed to recognise the skin imprints and destroyed them in the process of getting to the bones. I guess skin imprints are a rare thing and like a lot of palaeontology you really have to know what you are looking for, you must have a mental search pattern. There are lots of stories of things being missed and their significance only being ‘seen’ later. Fossilised embryos are a case in point...but that is another story.