|Riversleigh Fossil Centre||August 13 2021|
|We decided to visit the fossil centre having visited the
fossil site. And a couple of reasonable reviews.
Its part of a complex of tourist attractions. Built around the hard luck mine.
Independent of any museums or universities.
Outside is the three millionth copper anode produced at Mt Isa (1985). Brings back some memories of the Zambian Copperbelt with similar history and process.
|The visit to Riversleigh D site in early May piqued our
So far, from fossils at various sites in the area, 230 new species of fauna have been identified.
|First impression of a newly renovated centre is magic.
I'm usually in horror of anything beyond black type on white background. The centre has heaps of lighting to make the big coloured fonts legible to me.
One of those "it just works" places that takes many hours to design and set up but looks so obvious and simple.
We started on rocks from the fossil site. Chock a block full of fossils, some numbered and a key.
A description of Cambrian limestone that provided a source and home for tertiary, Cenozoic, limestone which contains the fossils. I haven't yet figured out where secondary fits.
Just like we read and saw at the site.
|The fossils have to be extracted from the limestone matrix.
There's a long list of what we see here, from bat parts to the teeth of other mammals.
The bats are important as not only did they eat small mammals but also provided the undigested bones and the guano added to the squishy limey mud in the bottom of caves that aided fossilisation.
|We moved through various mammal types.
This was a platypus. A comparison of skulls with present day platypus.
Larger and with teeth the now extinct fossil platypus probably ate different food.
|The fossilised koalas are about 1/3 the size and with a
more varied diet than our current version that has evolved to eat solely
The fossil record can be a record of evolution.
|Kangaroos evolved later than koalas. There are more
examples of fossilised kangaroos than koalas, which had presumably moved to
a different area as they evolved.
The kangaroo fossil record is one of evolution from a step to a jump, and a change of food.
Articulated fossil bones are much more use than randomly distributed bones. Riversleigh mud provided rapid fossilisation and protection from scavengers allowing a deeper analysis.
Also useful are the indents in bones where muscle tendons were attached. The evolution of larger muscles required for hopping has apparently been noted.
And of course teeth. So important in identifying likely food source.
The kangaroos moved to a drier climate, from rain forest and occasionally perhaps meat, to eating grasses on the plains.
|A marsupial lion. About the size of a dog.|
Some of the rock has been removed (more about that later) leaving lots of vertebrae.
Some of the fossil snakes were very much bigger than present day snakes. Fortunately they were unable to dislocate their jaws so their prey was a lot smaller than perhaps expected.
Apart from which its a quite beautiful bit of rock.
|A selection of "giant narrow mouthed snake" fossil bones.|
|Yup. The crocodiles were different too.
Cleaver-headed. Land dwelling part of their time, possibly even tree climbing.
The first specimen prised from the rock had the skull of a marsupial lion in its mouth.
Articulated bones that give clues to the angles at which front legs functioned. Walking is quite different to swimming.
|Alan's enthusiasm is infectious. He's been collecting
fossils for many a year. A chance encounter with some scientists near the
Gregory River more than 30 years ago.
Dromornithids, known only in Aus, were up to 4m high. Extrapolated from a thigh bone ... didn't we see one of those at the site?
The electronics worked (how disappointed I've been in museums where they aren't maintained). The young lady is stood in a place where a sensor detects her movement, and the big bird moves accordingly.
|Enough microscopes to go round, and some left over.
2x magnification. Enough to see which teeth hadn't been cleaned .....
|An insight into the relationship between the centre and the
academic world of fossil research.
"The only" known fossil specimen of the tip of the lower jaw of a dromornithid. Alan's concern that "the scientists" may take it from him showed for a moment.
Apart from which. Knowing what the tip of the jaw looks like is kinda important when artists begin extrapolating images from the bones. Plus a clue to what they (the dromornithids not the artists) ate.
|Acetic acid. Around 70-80%. Household vinegar is around
A slow process. And there is no way currently of knowing what is inside the rock until at least some of it shows.
|Just my reminder.
Paraloid has been used to glue bone fragments together for a complete bone.
An acetone soluble resin. I may have a use for it.
|A mix of bone and tooth fragments sifted out of what is left when the rock is dissolved.|
|The caves and lakes the fossilised fauna fell into were
As well as the mud there is flowstone, with channels that collect "stuff".
As mentioned earlier there's also bat poo.
|Close up of the bit of rock on the right. A collection of
teeth and bones.
I guess at the site I'd been introduced to the big, publicity gaining, fossils. Low frequency high value fossils.
This collection is equally important, telling a story of life at the time.
|The artists have had their turn at the centre.
The odd looking snout on this palorchestes, a bit wombat like, isn't just a flight of fancy. The nasal passages of mammals with trunks are so very different, entering the skull above the eyes.
There are so many clues. So many clues that, in Alan's words, tell a story.
There's even real water flowing through this part of the display. So much more authentic than a recording.
If I haven't conveyed how impressed I was with the centre I should reinforce that now.
But I can't think of any better superlative than "magic" that I used at the beginning of this page.
The blog is mainly my own reminder of where I've been and what I've seen. Perhaps in this case something more.
|Through Boulia to Diamantina National Park||August 13 - 15 2021|