When did domesticated house cats become the tiny but amusing tyrants they are today? At what point did the sabre-teeth and ferociousness of their ancestors drop away to create the cute conical-teethed stars of funny Internet pictures such as this one here? Or maybe this one? It can be difficult to choose a favorite, but each one has a skull and those skulls can be measured.

Dr. Manabu Sakamoto and Dr. Marcello Ruta at the University of Bristol’s School of Earth Sciences compared the skulls of dead cats: extinct sabre-toothed cats, modern or conical-toothed cats, and prehistoric ‘basal’ (a fancy word for basic) cats who are the ancestors of modern cats.  They wanted to see where the evolutionary branches of the species occurred through the history of the cat skull.

The paper is called: “Convergence and Divergence in the Evolution of Cat Skulls: Temporal and Spatial Patterns of Morphological Diversity” and it was published online earlier this month on PLoS ONE.

Sakamoto and Ruta measured cat skulls and placed them on a timeline to discover how they changed during evolution of the cat family tree. Their research showed “an early and conspicuous divergence” between the conical-toothed cats and sabre-toothed cats.  All of the sabre-toothed cats they looked at were more closely related to each other than they were when compared to modern cats.

The skull shape research also showed a defined and early separation in the evolutionary history of modern small-medium cats, a category that includes domesticated cats and their next of kin -cheetahs, pumas, and lynxes- and the modern big cats we commonly see at the zoo.

Sakamoto said in a statement about the research: “Our study is the first to determine the interrelationships between modern conical-toothed cats, sabre-toothed cats, and some basal cats.

It also highlights how simple measurements can be used not only to investigate shape-space distribution, but also to successfully discriminate and identify different cat species – this could be useful for museums who may have as yet unidentified cat specimens in their collections.”

The measurements could clear up any doubts museums have about skulls in their collections too.

Sakamoto maintains a personal blog, Raptor’s Nest, where you can read more about the cat skull evolution study, his passion for the field of paleontology, and his musings about science and life.

Raptor’s Nest even has a tip for checking if your milk has “gone off“ (expired) so you can be sure it’s safe before giving it to your conical-toothed deathmachine known as Fluffy or Mittens.