| Similarity | Rank | |
|---|---|---|
| permian | 0.895 | 18568 |
| triassic | 0.885 | 19513 |
| silurian | 0.882 | 24411 |
| cretaceous | 0.880 | 15845 |
| eocene | 0.878 | 39949 |
| devonian | 0.873 | 17422 |
| precambrian | 0.871 | 28924 |
| ordovician | 0.866 | 22032 |
| palaeozoic | 0.864 | 17635 |
| crinoid | 0.854 | 42572 |
| ammonoid | 0.849 | 43985 |
| pleistocene | 0.848 | 19850 |
| miocene | 0.841 | 31987 |
| oligocene | 0.837 | 52381 |
| brachiopod | 0.837 | 24768 |
| carboniferous | 0.835 | 10443 |
| dicynodont | 0.832 | 72125 |
| unconformably | 0.830 | 99989 |
| nautiloid | 0.828 | 49926 |
| metamorphic | 0.828 | 30217 |
| cainozoic | 0.827 | 58574 |
| proterozoic | 0.825 | 68404 |
| glaciate | 0.824 | 54958 |
| breccia | 0.821 | 37637 |
| glossopteris | 0.820 | 77276 |