Not all kinds of muscle scaling give the same results.

Check out this paper to see which method of muscle scaling to use in comparative FEA to best address your hypothesis.

We put this to the test on an extinct species of desert bettong, Caloprymnus campestris, which may or may not be extinct.

Did good press with this one!

It’s been a common practice in the field to remove shape variation related to size, in order to focus on shape related to functional adaptation.

Here, we use nearly 400 rock-wallaby skulls to suggest that feeding adaptations that correlate with size can be lost using this approach.

Very important stuff - and landed us on the cover of the journal, no less!

Craniofacial Evolutionary Allometry (CREA) is a frequently observed pattern where the larger of two closely related species will often have a longer face.

Here, we presented a framework that can explain this effect in many cases.

Spoiler - it’s rooted in biomechanics!

Bettongs and potoroos of the marsupial Potoroidae family tend to eat nutrient-rich, highly digestible foods, similar to what humans look for!

We reviewed their diets and measured the material properties of their different foods for a better understanding of the biomechanics involved.

We looked at how the skulls of rodents change with dietary variation across their ranges of body size.

Rodents have a pretty conserved skull shape, mostly because it’s so specialised for incisor biting. But we still found some nice differences.

We looked at the prevalence and co-occurrences of different oral injuries and diseases in several species of baboons and macaques (Cercopithecoids).

Male-male competition is a probable cause for higher lesion prevalence in male baboons.

Orangutangs from Sumatra and Borneo have some differences in their diets.

We wondered if these differences would be seen in the microwear patterns of their teeth.

We didn’t find any support for this hypothesis, but these results are important to report as well.

The dingo barrier fence has isolated populations of red kangaroos from each other for more than a century.

Populations on one side of the fence live with lots of predatory dingoes, while those on the other side enjoy less stress with far fewer dingoes around.

Turns out they also grow up slower too!

We measured brain shape across 148 extant primate species and 6 fossil hominins.

While different parts of the brain develop more separately in other primates, these different parts of human and neanderthal brains grow and develop together.

This might have played an important role in the development of more complex behaviours!

We examined the shape variation in the jaw joints of 17 primate species.

Most variation was associated with size and how related the species are.

We discuss some cool biomechanics points as well.

We compared the biomechanical performance of the beak and talons across a range of predatory and scavenging birds.

Our results suggest that the Haast’s eagle killed like an eagle, but fed like a vulture.

This makes sense, as there is evidence it took down large bodied prey.

We used shape analysis to examine asymmetry in the skulls of gorillas, chimps, and macaques.

Chimps had lower asymmetry than the other two. We discuss the potential roles of stress and developmental differences in this result.

While unquestionably well-intentioned, too much chopping and dicing of foods for captive animals by carers can weaken their skulls over time. This might cause problems for reintroduction to the wild.

We demonstrated this using biomechanical simulations of 40 rat skulls fed diets of different hardness throughout their lives.

A lifetime of softer foods produced weaker skulls, potentially limiting their access to harder foods.

This is a gem of a paper. Not cited nearly enough.

A major consideration in shape analysis of skulls and other bones is which specimens are good enough to include in analysis.

We showed here that inclusion of damaged and diseased skulls in data sets does not necessarily impact the statistical evidence for major predictors of shape, such as size or sexual dimorphism.

In fact, ignoring some specimens because of damage or injury might be biasing the sample by excluding individuals that are more likely to be injured or diseased. Like large, fighting males, for example.

Through analysing brain shape across >150 primate species, we showed that strong shape differences associated with increased size were also related to more complex behviours.

Foraging behaviours can influence skull shape and structure.

A clear example of this can be seen in the skulls of grazing and browsing marsupial herbivores.

We tested this hypothesis between two subspecies of pademelon - one a night time grazer, the other a forest dwelling browser.

The browsing subspecies had significantly shorter faces, in agreement with broader patterns.

We described new cranial and postcranial material, including the most complete crocodyliform skeleton from the Cretaceous of New South Wales.

This was a fun paper.

I used fundamental theory of how skulls work to show that the extinct species probably had different jaw muscles to species around today.

I argue that its skull was functionally more similar to a panda than any kind of roo around today.

This work was showcased on the “Best of PLOS 2019” research list.

We used shape analysis on the skulls of a bunch of extant marsupial herbivores, such as koalas, wombats, and kangaroos, to estimate the diet of an extinct species of kangaroo.

We argued that the length of the face and its robusticity is largely determined by the hardest bites needed by the animal.

We compared skull shape and biomechanics with diet across 16 species of kangaroos, wallabies, and rat-kangaroos.

Species with diets involving harder anterior biting tended to have shorter faces.