Why I think the Jurassic/Cretaceous boundary is super important

Mass extinctions are insanely catastrophic, but important, events that punctuate the history of life on Earth. The Jurassic/Cretaceous boundary, around 145 million years ago, was originally thought of to represent a mass extinction, but has subsequently been ‘down-graded’ to a minor extinction event based on new discoveries.

However, compared to other important stratigraphic boundaries, like the end-Triassic or the end-Cretaceous, both time periods representing mass extinction events, the Jurassic/Cretaceous (J/K) boundary actually remains really poorly understood. This is both in terms of what was going on with different animal groups at the time, and what environmental changes were occurring alongside this.

Well, I have a new research paper out now that synthesises more than 600 research articles, bringing them together to try and build a single picture of what was going on around this time! It’s free to read here, and is essentially the literature review from my thesis, or as I like to think of it, the justification for my existence as a researcher!

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Your bite or mine?

This was originally posted at: http://blogs.egu.eu/palaeoblog/?p=1250

It rises from the dark waters like some behemoth from the deep, and lets out a blood-curdling roar. It’s feeding time. One of the most iconic scenes from Jurassic Park III is where the long-snouted, sail-backed giant theropod dinosaur Spinosaurus emerges from underwater to try, yet again, to eat our beleaguered rabble of misfortunates. It’s always been the way these dinosaurs have been portrayed, including one of Spinosaurus’ close cousins Baryonyx from the UK. With their long snouts, bulbous tips, and pointy teeth, it’s often been thought that spinosaurid dinosaurs were quite a lot like modern crocodiles. But how much of this is true?

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Another clue to the origins of dinosaurs

This was originally posted at: http://blogs.egu.eu/palaeoblog/?p=1222

Often the early evolution and radiation of the first dinosaurs is an overlooked part of their tale, in favour of the more dramatic but arguably no less important tales of their later radiations and extinctions. It is actually a fairly poorly understood part of their evolution too, with the timing, and actual mechanism that drove them to become the most successful land group ever still a bit of a mystery.

We are, however,  learning more and more about this important phase of their history, in a time known as the Late Triassic some 231-201 million years ago. A new fossil site from this time in Poland – probably not one of the places you’d associate with important fossils – is helping to fill in the blanks. Usually, dinosaur-bearing sites from around this time are known from the southwestern United States and southern South America, so a European locality can potentially tell us quite a bit!

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The greatest mass extinction in the history of life

This was originally posted at: http://blogs.egu.eu/palaeoblog/?p=1204

In palaeontology, there are so many things more important than dinosaurs. For example, the study of large-scale patterns in the history of life on Earth, commonly known as macroevolution, is all about uncovering patterns of speciation and extinction. We are currently about to enter the sixth mass extinction within the last 542 million years of life on Earth, so figuring out exactly what happened during periods of elevated extinction and ecosystem catastrophe is pretty damn important if we want to offset as much damage as possible.

Recently, a suite of new papers have been published giving detailed insight into the environmental and biological patterns and processes throughout the Permian-Triassic mass extinction, an event 252 million years ago that saw the demise of greater than 90% of life on this planet (numbers vary depending on which measure you use). What I’d like to offer here are bitesize summaries of each, and show that there is much more important research out there in palaeontology than just ‘woo new dinosaur’.

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How do the chemical ghosts of dinosaurs help their preservation?

This was originally posted at: http://blogs.egu.eu/palaeoblog/?p=1093

For some years now, Mary Schweitzer and her team have been researching the idea that organic molecules can be preserved for millions of years, specifically within dinosaurs. They have used a plethora of chemical and biotechnological techniques to demonstrate that, within animals like Tyrannosaurus rex, it is possible to find the residue of structures such as blood vessels and even proteins. Naturally, her research has been met with a whole wad of stiff resistance from the scientific community, seemingly for no other reason than “We don’t like the sound of that..”. Scientific rigour ftw!

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