Tommyplodocus

@nataliajagielska.bsky.social has been supporting a great cause with Doodles for Hong Kong, even sketching my favourite Cambrian arthropod, Opabinia regalis.

Very cool! Thank you.

For the last #FossilFriday of 2025, I’m sharing my favourite group of armoured fishes. Placoderms were an ancient group of fishes that lived during the Silurian and Devonian, between 430 and 360 million years ago. These examples show just how varied their morphology was.

Wishing everyone a Happy Christmas!
Behind door 25 of the Fossil Advent Calendar is Lambeosaurus lambei. This example was a juvenile that lived 75 million years ago during the Cretaceous period and was found in Alberta, Canada.

Christmas Eve and day 24 of the Fossil Advent Calendar! Behind today’s door is Bothriolepis canadensis, a placoderm that lived 375 million years ago during the Devonian Period. This example was found in Quebec, Canada.
Come back tomorrow for one last door!

Day 23 of the Fossil Advent Calendar is also #TrilobiteTuesday! Thysanopeltis speciosa was a trilobite that lived 389 million years ago during the Devonian period. This example was found in Morocco!

Door 22 of the Fossil Advent Calendar reveals Haplophrentis carinatus, an invertebrate that lived 506 million years ago during the Cambrian period. It lived on the sea floor and had a long, conical shell. This example was found in British Columbia, Canada.

A fish from the Age of Fishes for day 21 of the Fossil Advent Calendar! Eusthenopteron foordi was a lobe-finned fish that lived 375 million years ago during the Devonian period. This example was found in Quebec, Canada.

A slab of trilobites hides behind door 20 of the Fossil Advent Calendar! Pseudogygites latimarginatus lived 450 million years ago during the Ordovician period. This group was found in Ontario, Canada.

A trilobite for this #FossilFriday! Pseudogygites latimarginatus lived around 486 million years ago during the Ordovician Period. This example was found in Ontario, Canada.

It's #FossilFriday and Day 19 of our Fossil Advent Calendar! Today we have Eramoscorpius brucensis, an extinct species of scorpion that lived 432 million years ago during the Silurian Period. This example was found in Ontario, Canada.

A Carboniferous monster hides behind door 18 of the Fossil Advent Calendar! Tullimonstrum gregarium, better known as the Tully Monster, was a soft-bodied marine creature that lived around 310 million years ago. This example was found in Illinois, USA.

Door 17 of the Fossil Advent Calendar reveals Yawunik kootenayi, an arthropod that lived 506 million years ago during the Cambrian period. This example was found in Kootenay National Park, British Columbia, Canada.

Another trilobite hides behind Door 16 of the Fossil Advent Calendar for #TrilobiteTuesday! Olenellus clarki lived around 512 million years ago during the Cambrian period, with this example found in California, USA.

One of my all-time favourite Cambrian fossils is hiding behind Door 15 of the Fossil Advent Calendar: Opabinia regalis. This remarkable creature lived around 506 million years ago, with this example having been found in British Columbia, Canada!

The Fossil Advent Calendar gives us Amiskwia sagittiformis for Day 14! This organism lived around 506 million years ago in the seas of the Cambrian period, with this example found in British Columbia, Canada.

Door 13 of the Fossil Advent Calendar reveals Canis lupus, better known as the Grey Wolf. Grey wolves have been around for hundreds of thousands of years, with this example dating to around 21,500 years ago.