Table 1.
Specimens examined in this study
| Taxon | Specimen | Element | Length (mm) | Locality | Age |
|---|---|---|---|---|---|
| Aptenodytes forsteri | AMNH 3728 | Humerus | 125.5 | Antarctica | Modern |
| Aptenodytes forsteri | AMNH 3728 | Femur | 122.2 | Antarctica | Modern |
| Aptenodytes forsteri | AMNH 3728 | Tibiotarsus | 198.6 | Antarctica | Modern |
| Spheniscus sp. | AMNH 1626 | Humerus | 71.7 | Chile | Modern |
| Spheniscus sp. | AMNH 1626 | Femur | 82.8 | Chile | Modern |
| Spheniscus sp. | AMNH 1626 | Tibiotarsus | 114.3 | Chile | Modern |
| †Palaeospheniscus patagonicus | AMNH 3287 | Humerus | ∼75 | Gaiman Fm., Argentina | Miocene |
| †Palaeospheniscus patagonicus | AMNH 3349 | Femur | ∼84 | Gaiman Fm., Argentina | Miocene |
| †Palaeospheniscus patagonicus | AMNH 3321 | Tibiotarsus | ∼110 | Gaiman Fm., Argentina | Miocene |
| †Small Eocene stem penguin | USNM 404461 | Humerus | ∼80 | La Meseta Fm., Antarctica | Eocene |
| †Small Eocene stem penguin | USNM 404459 | Femur | ∼90 | La Meseta Fm., Antarctica | Eocene |
| †Large Eocene stem penguin | USNM 404477 | Humerus | ∼160 | La Meseta Fm., Antarctica | Eocene |
| †Large Eocene stem penguin | USNM 402616 | Femur | ∼130 | La Meseta Fm., Antarctica | Eocene |
| †Large Eocene stem penguin | USNM 402351 | Tibiotarsus | ∼225 | La Meseta Fm., Antarctica | Eocene |
| Calonectris borealis | BRCM 2015.04 | Humerus | 133.4 | North Carolina, USA | Modern |
| Calonectris borealis | BRCM 2015.04 | Femur | 44.9 | North Carolina, USA | Modern |
| Calonectris borealis | BRCM 2015.04 | Tibiotarsus | 97.5 | North Carolina, USA | Modern |
| Gavia immer | BRCM 2015.03 | Humerus | Incomplete | Unknown | Modern |
| Gavia immer | BRCM 2015.03 | Femur | Incomplete | Unknown | Modern |
| Gavia immer | BRCM 2015.03 | Tibiotarsus | Incomplete | Unknown | Modern |