“It’s not a penguin.” That thought occurred to me as I stood among Museum Victoria’s vast Geosciences Collection pondering the identity of a 9 cm-long honey-coloured fossil. It was 2004, and I was a PhD student immersed in the esoteric world of fossil whales.
So why was I studying a bird? How did I know that this one bone was not the relic of a primordial penguin? And if it wasn’t a penguin, what kind of bird was the former owner of this bone? Why does it matter anyway?
The solution to these riddles spans 60 million years of the Earth’s history, 7 years of human endeavour and the entire globe. But it begins with a chance discovery on a Melbourne beach. Let me explain.
By a wonderful coincidence of geology and human history, a window into the Southern Ocean’s past occurs within metropolitan Melbourne at Beaumaris, a suburb just 20 km south-east of the city centre. This gateway to deep time is manifested in sandstone that forms cliffs, erodes as beach boulders and pebbles, and lines the shallow floor of Beaumaris Bay. These sedimentary rocks were laid down in a shallow coastal sea during the late Miocene and early Pliocene epochs 5.0–6.0 million years ago. This comparatively recent twinkle in the eye of geological time bore witness to a world in which we would find much that is familiar, as well as the startlingly unexpected.
The incessant...