Table 2.
Cranial events ranked according to relative timing of onset of ossification
| E. europaeus | E. amurensis | Cr. parva | Ch. platycephala | Su. murinus | Co. cristata | Sc. orarius | U. talpoides | M. wogura | T. europaea | T. occidentalis | Myotis | Tupaia | Rattus | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Premaxilla | 1 | 1 | 1 | 2 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 2 | 2 | 2 |
| Maxilla | 1 | 1 | 1 | 2 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 2 | 1 |
| Palatine | 3 | 3 | 2 | 2 | 3 | 1 | 1 | 1 | 2 | 1 | 1 | 6 | 3 | 2 |
| Dentary | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 |
| Frontal | 1 | 2 | 2 | 2 | 2 | 1 | 1 | 1 | 2 | 1 | 2 | 2 | 4 | 1 |
| Parietal | 4 | 1 | 3 | 2 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 2 | 4 | 2 |
| Squamosal | 4 | 3 | 5 | 2 | 4 | 2 | 2 | 2 | 2 | 2 | 3 | 2 | 4 | 2 |
| Basioccipital | 5 | 3 | 6 | 3 | 3 | 1 | 5 | 3 | 3 | 2 | 1 | 8 | 6 | 2 |
| Nasal | 4 | 3 | 4 | 2 | 5 | 1 | 1 | 6 | 2 | 2 | 2 | 7 | 7 | 3 |
| Pterygoid | 1 | 3 | 3 | 2 | 4 | 1 | 1 | 1 | 2 | 2 | 4 | 3 | 5 | 2 |
| Exoccipital | 5 | 3 | 6 | 2 | 4 | 1 | 2 | 4 | 4 | 3 | 1 | 10 | 7 | 2 |
| Basisphenoid | 4 | 3 | 8 | 5 | 6 | 4 | 3 | 5 | 7 | 4 | 6 | 9 | 9 | 4 |
| Lacrimal | 6 | 5 | 6 | 6 | 5 | 6 | 1 | 8 | 4 | 4 | 3 | ? | 5 | 3 |
| Alisphenoid | 5 | 3 | 9 | 6 | 8 | 8 | 7 | 8 | 8 | 7 | 8 | 9 | 7 | 4 |
| Orbitosphenoid | 5 | 4 | 10 | 6 | 9 | 7 | 6 | 7 | 6 | 6 | 7 | 12 | 9 | 7 |
| Petrosal | 7 | 8 | 11 | 7 | 10 | 9 | 7 | 8 | 8 | 7 | 9 | 11 | 11 | 6 |
| Mastoid | 7 | 9 | 12 | 7 | 11 | 5 | 5 | 6 | 5 | 4 | 3 | 11 | 11 | 7 |
| Vomer | 2 | 3 | 2 | 2 | 5 | 1 | 1 | 1 | 2 | 1 | 1 | 8 | 5 | 2 |
| Presphenoid | 7 | 9 | 13 | 8 | 11 | 9 | 7 | 8 | 8 | 7 | 10 | ? | 10 | 6 |
| Supraoccipital | 5 | 3 | 5 | 2 | 3 | 1 | 2 | 5 | 2 | 2 | 1 | 9 | 8 | 5 |
| Ectotympanic | 6 | 6 | 6 | 4 | 7 | 3 | 2 | 8 | 6 | 5 | 5 | 5 | 6 | 3 |
| Goniale | 6 | 7 | 7 | 6 | 8 | 6 | 4 | 8 | 2 | 5 | 7 | 4 | 6 | ? |
Data for three boreoeutherian outgroup species, the greater mouse-eared bat (Myotis myotis), the common treeshrew (Tupaia glis), and the Norway rat (Rattus norvegicus) were compiled from the literature [44-46]. Simultaneous events are usually the result of low resolution of sampling, since the onset of ossification of two bones is unlikely to occur exactly at the same time. Therefore, the resolutions for oral bones in Co. cristata, Sc. Orarius, U. talpoides, and T. europaea are limited in this study.