My interview with Imperial College on the rise and fall of ancient dinosaur-eating crocodiles

While back in London recently for my PhD viva, the opportunity came up to speak with the Communications Office at Imperial College about some of my research. Naturally I pounced at the chance to discuss my research and broadcast it to a wider audience. The short audio for the interview is now online here, and we discuss everything from the impact of changing climates on biodiversity to giant, dinosaur-devouring crocodiles! Enjoy 🙂

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Dr Jon Tennant studied these creatures as part of his PhD in theDepartment of Earth Science and Engineering. He was exploring the biodiversity and the extinction of some tetrapods, which is a classification for all creatures with four limbs.

Dr Tennant, who is also a science communicator and children’s author, looked at some of the most fearsome tetrapods of them all – crocodilians. These creatures, which alligators and crocodiles are modern ancestors of, lived on Earth over one hundred million years ago in the deserts, coasts, oceans and even the artic regions of our planet. Some, like the Sarchosuchus, were the size of double-decker buses, and going by the fossil evidence, fed on dinosaurs, who were rival ‘apex’ predators.

Dr Tennant discovered in his research that changes in sea level, brought on by fluctuations in the climate and continent movements, changed the world of tetrapods like the Sarchosuchus forever. Now, he is embarking on a six-month exploration of the planet, including some of the regions where modern crocodilians live. Colin Smith caught up with Dr Tennant to talk about his favourite ancient crocodilians and how changes in early Earth impacted on their biodiversity. 

Full podcast here and you can download the mp3 file here.

Ecological reshuffle following a crocodyliform extinction

Chaaaaange places! Sometimes, when extinction hits it’s not quite the dramatic ‘great dying’ we might think of where animals choke their final breaths out in the desolate, lifeless wastelands. Sometimes, it’s more like the Mad Hatter’s tea party from Alice in Wonderland: chaotic, messy, no major character dies, but you can be sure that something pretty weird and dramatic has just happened.

Well, I think this is what happened around 145 million years ago at the Jurassic/Cretaceous boundary. In a recent paper, we analysed the diversity and extinction patterns of crocodyliforms – the group that includes modern crocodiles and their super cool ancestors – and found that they got hit pretty hard by an extinction event around this time.

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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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The Cambridge Science Festival

This originally appeared at: http://blogs.egu.eu/palaeoblog/?p=1152

Last night, I was honoured to have spoken at the final evening lecture at the Cambridge Science Festival, along with Nick Crumpton, Anjali Goswami, Rob Asher, and Stephanie Pierce, about why palaeontology is important. Below is a rough transcript of some of what my talk was about. Unlike the others, I didn’t discuss my own research. Instead, by general gist was that although palaeontology is useful in addressing some of the greatest scientific questions of our time, like the evolution and history of life on Earth, the current narrow framing of science in terms of impact is being quite detrimental to creativity and exploratory science. As such, should palaeontology be more focused on its emotive qualities, and be used as a ‘hook’, or ‘gateway’ into the other fields of science?

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Green tea and Velociraptors turns into beer and dwarf crocodiles

This was originally posted at: http://blogs.egu.eu/palaeoblog/?p=825

I’m in Berlin. I’ve just managed to find a chicken donner kebab, and am pausing research briefly to write this. I’m currently on leave from London, with a ridiculously hectic couple of months ahead: I’ve just been to Munich to see a dwarf crocodile specimen, Alligatorellus beaumonti (from Bavaria), which conveniently happened to coincide with Oktoberfest, and am now here to visit another specimen, Theriosuchus ibericus, from Spain. Preliminary glances at the material in Berlin makes me think the Spanish material may be a new genus altogether (whatever that actually means), and another broken up specimen of Alligatorellus might be a new species, based on what I can tell from it’s body armour (yeah, these crocs were awesome!)

Alligatorellus beaumonti, holotype specimen. Copyright: Bavarian State Collection, Munich

Alligatorellus beaumonti, holotype specimen. Copyright: Bavarian State Collection, Munich

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