That sexual selection is one of the primary drivers in evolution is well established. Studies of Mesozoic #dinosaurs and #pterosaurs, however, have been dominated by the view that the variation, extravagance and diversity seen in these animals is not due to the pressures of sexual selection, but...

Spiny little friend. A quick doodle of Haolong dongi, a newly described ornithopod from China with... spikes. Numerous sharp spines grew from the animal's neck and back, seemingly different from all other known dinosaur integuments. Definitely wasn't on my bingo card for 2026 dinosaur finds!

Reindeer Days Back in the Pleistocene, reindeer were found as far south as Spain. While many populations today are endangered, there are also semi-domestic reindeer. I met this pair in the Finnish far north, just jogging along the road. It's such a unique animal and always a joy to see.

The reign of the orange tyrant is soon to be over! Sadly, I don’t mean the one you’re probably thinking about (though one can hope). I mean Rufus, who has the questionable honor of being my meanest rat ever. He finally had a hormone-blocking implant installed today. A small thread!

A lovely example of rat empathy from last night: Lumo (black and white) notices little Reino is in pain, consoles him with a bit of grooming and quickly checks his hurt foot before giving him space. No worries, it was just a strained muscle. He was fine after pain medication and 12 hours of rest.

Curious noses. This is the sort of welcome you get arriving home to your boy rats after visiting some girl rats. Or vice versa. Like dogs, rats can learn much from each other’s smell - health, diet, relatedness, immune system compability. Imagine being able to do that with humans!

Christmas break fantasy doodles, before work resumes tomorrow. A wild winged unicorn and a dragon peeking into an abandoned garden.

Sad news: As of this year, Finland allows the killing of about a fifth of our grey wolf population annually, regardless of whether the particular wolves cause any harm. This on top of harm-based permits and poaching puts our endangered wolf population at risk. More info: www.sll.fi/ajankohtaist...

Last art of the year! #SciArt As a fun pastime on my Christmas break, I looked into basal ceratopsians a bit and doodled them. Turns out they vary from cuddly little guys to beasts that would have made a mighty (and very bitey) steed. Close-ups of each one in thread 🧵:

As far as we know, vertebrate animals have equally deeply experienced emotions regardless of size or expressiveness. And sometimes, it really comes up to hit you in the face. These two are the brothers of my recently deceased Taika and Nikos - and both got ill from the stress of losing them.

Nice puppy... I hope. Borophagines, or bone-crushing dogs, are an extinct group of canids with hyena-like teeth, wide skulls and high foreheads, somewhat resembling domestic dogs such as Rottweilers and mastiffs. I wonder if they had the same powerful-but-cute look? Just a goofy little doodle.

Animals with misleading names. I'm seeing this go around as part of a viral tumblr thread so I thought I'd reshare it.

Vielä ehtii jouluksi! 🎄🎅 Jos tilaat viimeistään to 18.12. www.aradorsuomi.fi/kauppa saat kirjasi viimeistään ti 23.12. Myymäläsaatavuus: Tällä hetkellä Koiran mieli löytyy ainakin Akateemisesta kirjakaupasta ja Turun Sarjakuvakaupasta. Kuvassa pakataan tänään Aradorista lähteviä kirjoja 😊

Flirting Diplodocus. A new study was able to locate melanosomes inside fossilized diplodocid scales. It concluded they had patterns and several types of pigment. Here's a somewhat creative interpretation on their possible appearance. #SciArt royalsocietypublishing.org/rsos/article...

With pets, heartbreak is inevitable, but wow, does it sometimes come in shocking ways. We lost both Taika and Nikos last weekend, within a day of each other.

We had sunlight today! It was, in fact, such an unusual occurrence it was featured on national news (with a livestream, no less).

It was so much fun getting to meet different dogs to create the characters for our science comic book, The Mind of a Dog. Milo was based on a young and very enthusiastic Dachshund called Mauri.

Tänään ja huomenna Koiramessuilla Helsingissä. 🐕

Do you know a dog owner who would be delighted to get this for Christmas? #dogs #comics #nonfiction #books #christmas

Onko lähipiirissäsi koiraihminen, joka ilahtuisi tällaisesta pukinkontissa? Katso näytesivuja: www.arador.fi/koiranmieli #koirat #lemmikit #kirjat #tietokirjat

At this time of the year, I find myself daydreaming about faraway places. I miss sunshine and warmth, tall mountains and blue seas and green forests. And insects. This was the front cover of children's magazine Sieppo a few years ago, set in the Sinharaja rainforest reserve in Sri Lanka.

So happy to announce our new preprint, “A geothermal amoeba sets a new upper temperature limit for eukaryotes.” We cultured a novel amoeba from Lassen Volcanic NP (CA, USA) that divides at 63°C (145°F) 🔥 - a new record for euk growth! #protistsonsky 🧵

Yesterday we had a special #MonkeyCruise stream in honor of Jane Goodall! Her contributions to primatology and our understanding of animal intelligence changed the worldview of whole generations and her caring and critical voice will be missed. Referenced artworks below...

A little chain of scritches.

Spiny friends! Stegosaurs bore a fantastical variety of bony plates, spines and osteoderms, probably a mix between ornamental, defensive and offensive.

Shelter cats. I visited the animal shelter at Lohja, southern Finland, in preparation for an upcoming book project. Despite decades of work, cats still end up in shelters in shocking numbers. I’m not usually a cat person but seeing these poor guys, I might have taken a few home with me if I could.

Wake me up when spring comes, please.

Phew, finally done with the introductions! It took almost three weeks this time, but all the big boy rats have now accepted the newcomers. There doesn't seem to be any rule to the varying difficulty of rat introductions. It can take a couple of ours or a month - just roll the dice and try.

I haven’t had much time for drawing anything personal lately, but here’s a quick doodle of my rat Hönö, who curled into this seemingly very uncomfortable position and then promptly fell asleep using himself as a pillow.

Beginning of the Polar Night. It's this time of the year again - sun barely rises and is most of the time obscured by clouds. Back in the Cretaceous, Arctic winters would have been even darker and greyer: warmer climate meant little snow, and studies suggest a permanent polar cloud cap. Poor dinos.

Spiny friends! Stegosaurs bore a fantastical variety of bony plates, spines and osteoderms, probably a mix between ornamental, defensive and offensive.

Tulkaa tällä viikolla moikkaamaan kirjamessuille! 😊 If you happen to be around Helsinki this week, come meet me and @villesinkkonen.bsky.social at the book fair!

These are seriously wonderful books with so many talented artists featured! I'm honored (and still a bit amazed) to be featured in part II.

Pet rat update: we have new babies! 💗 These adorable little boys moved in a week ago. I’ve been getting to know them, trying to think of names and slowly introducing them to the big boys. It has been a bit more of a hassle than anticipated. A little thread on introducing new pets to older ones.

Our new book of nonfiction comics is out now! 🎉 In English: www.arador.info/mindofdog In Finnish: www.arador.info/koiranmieli Created by the same scientist-artist team as the multiple-award-winning book "The Mind of a Horse. Science Meets Comics" 🏆 #dogs #pets #animals #nonfiction #comics

Nyt se on ilmestynyt! 🎉 Loistava lahjaidea tai iloksi itselle. Sopii aikuisille ja nuorille. Katso näytesivuja suomenkielisestä kirjasta: www.arador.info/koiranmieli Check out sample pages of the English-language book: www.arador.info/mindofdog #koirat #lemmikit #eläimet #tietokirjat #sarjakuvat

Goblins behind a screen of feathers, old and new. Since living dinosaurs look somewhat unhinged without their feathers, the same was probably true of their ancient non-avian cousins, such as Velociraptor. #Sciart

The earth has reached its first catastrophic tipping point linked to greenhouse gas emissions, with warm water coral reefs now facing a long-term decline and risking the livelihoods of hundreds of millions of people, according to a new report. www.theguardian.com/environment/...

October moths Even now it’s not too late to cling to the last remnants of summer and go looking for moths. These are some of the species that can still be seen in Finland & elsewhere in Northern Europe, drawn after my own photos.

Pet rat update! Today, I’d like to introduce Elmo, one of the six-month old teenagers. He’s not only very cute, but also has some interesting genetics – a homeobox mutation, temperature-dependent albinism, and a complex ancestry. Here's a thread on pet rat genetics.

"Similar radiocarbon dates for woolly mammoth and woolly rhino fossils from the same sites imply the presence of both faunas during this period." 🦣🦏🦛

Nähdään parin viikon päästä Kirjamessuilla!

Drepanosaurs have such character! Drepanosaurus, a Late Triassic arboreal reptile not closely related to anything living today. #Sciart

I missed World Animal Day, but here in Finland, it's an entire theme week. This year, it's about the welfare of small furry pets: rodents and rabbits. They make amazing pets when treated right - but they are not the "easy" children's pets often thought. Could also be #Rattober 1 - Friend-shaped rat

Dr. Jane Goodall filmed an interview with Netflix in March 2025 that she understood would only be released after her death.

Well, looking at this! I went hunting for wild truffles and brought this truffle-scented tissue for the rats. Taika's first idea was to grab it and bring it to me. Taika has such a keen interest in mushrooms I'm sure he would be an excellent searcher if I could take him into the woods safely.

Sad news: the kakapo population is down to 237 after a female bird called Solstice died of an infection. According to the Kakapo Recovery Facebook page, she had • 8 clutches • 24 eggs laid • 13 fertile eggs • 6 chicks hatched • 4 living offspring • 27 descendants

A lovely story about Dr Jane Goodall's career & legacy, from Rachel Fieldhouse & Mohana Basu, in @nature.com www.nature.com/articles/d41.... Includes some comments from me about how researchers _can also_ be advocates and science communicators, and still be taken seriously (I hope)! Vale, Jane.

Another Triassic oddball: Hypuronector. This little one looks like he has an attitude. Since the publication of a feather-like crest on related Mirasaura, it’s plausible to imagine other drepanosaurs also having something similar - perhaps they just haven’t been preserved.

I hope people spend days and days talking about her (she is 10,000,000 times more important than Charlie Kirk) and the amazing work she did. This photo will always be so powerful and as defining of who we all can be. Be like Jane Goodall. Photographer: Hugo van Lawick