Dunkleosteus

Dunkleosteus marsaisi replica skull on display at the Museum of Natural Sciences of Barcelona | Credit: Talita Bateman

I don’t usually write about fish and, in general, don’t tend to focus much on ichthyology - but take me to a natural history museum and you will see me hunting for a Dunkleosteus. Can you blame me? They were pretty impressive creatures, just look at the image above. Talk about science fiction meets reality, right?!

My brother, on the other hand, has always been fascinated by fish - especially whale sharks. Every single aquarium that we have ever had growing up was carefully curated by him. At 12, he was attending courses on aquarism and lecturing my parents on what we needed for the aquariums and why. He is currently attending university in Norwich and my mother will often call him from Brazil to update him on how the aquarium and all the creatures in it are doing and ask for advice if she has any issues.

My brother’s beloved Hillstream Loach | Credit: Caio Biasoli

Despite his preference for fish, we both grew up with tremendous love and respect for all animals, something my mother taught us from a very young age. Perhaps one of our main bonds growing up was our childhood obsession with Dinosaurs and other extinct creatures. I lost count of how many times we watched The Land Before Time and Jurassic Park, or how many hours we spent watching the Discovery Channel or the National Geographic Channel.

I went to visit him in Norwich a few weeks ago and we stopped by Waterstones to browse for books. Near the stairs on the ground floor, I found a little Schleich shelf and automatically started checking what species they had. My brother joined me and immediately clocked on the Dunkleosteus toy. Not only did it look awesome, but you could also move its jaw! Needless to say, I bought him the Dunkleosteus and since today is my little brother’s birthday, this post is dedicated to him.

My little brother posing with his whale shark and dunkleosteus toy | Credit: Caio Biasoli

I recently wrote about Ichthyosaurs, giant extinct marine reptiles that first appeared around 248 million years ago. However, even before these giants were roaming the sea, around 360 million years ago, Dunkleosteus was one of the largest group of fish of the late Devonian period. You may often hear them referred to as armoured and looking at their skull, you can sort of understand why. They belonged to an order of extinct armoured jaw fish called Arthrodira and were formidable predators.

Despite all the imagery of those huge nightmare-ish front teeth, true teeth they were not! Instead, they had bony plates that protruded from their skull and looked like sharp fangs. Dunkleosteus kept these bony plates sharp by scraping them together and they ate pretty much anything including each other.

Cannibalism may seem shocking to some but many living species of animals can display cannibalistic behaviour sometimes, even ones commonly regarded as ‘cute’ such as rabbits. With adults measuring up to 6 metres in length, weighing up to a ton and showing cannibalistic behaviour, I’d imagine that any juveniles that managed to reach adulthood were pretty tough little (big) guys. In fact, these characteristics point towards the likelihood that during their time on Earth, these creatures were at the top of the food chain.

To end this post I would like to wish my little brother a very happy birthday! I am so proud of you and love you more than I can express in words. Enjoy your day!