Published on October 1st, 2021 | by David Marshall Episode 129: Penguins
Whether it’s because of their unique shape, comical walking or extreme ecology, there’s no denying that penguins are incredibly popular and charismatic animals, but what actually makes a penguin a penguin and how are they different from other birds? Have penguins always been, well, “penguiny”?
Joining us for this interview are Simone Giovanardi and Daniel Thomas who have just described a new species of giant penguin from New Zealand. Together, we explore penguin evolution and how their new species
Kairuku waewaeroa fits into this story.
Their open access article can be found
Kairuku waewaeroa is a new species of giant penguin found in the Oligocene-aged rocks of the Glen Massey Formation, in the Waikato District of the North Island of New Zealand. Credit: Dr Daniel Thomas
The penguin was entirely contained within a single block of siltstone and was discovered, prepared and donated by the children of the Hamilton Junior Naturalist Club. From this angle, you can see how all the bones lie on a single plane, indicating that the skeleton is articulated in approximately the same position as it was when it settled onto the ancient sea floor. Credit: Dr Daniel Thomas
The specimen is relatively complete and well preserved for a fossil penguin since many other species are known from just a few bones. In general, penguins have a better chance of being preserved in the fossil record on account of their thicker bones. Credit: JVP
K. waewaeroa has a distinctively rounded elbow. Image: Wing elements of Kairuku waewaeroa: A, B (right humerus) G & H (right radius); Kairuku grebneffi: C, D, E, F, K, L; and Kairuku waitaki: I, J. Credit: JVP
Preservation of fine details upon the humerus, including a mark left by a blood vessel. Credit: Dr Daniel Thomas
It also has slightly longer legs than other Kairuku species, hence the species name ‘waiwairoa’ meaning long legs in Te reo Māori. Image: Femora of Kairuku waewaeroa: A, B; Kairuku sp.: C, D; Kairuku grebneffi: E, F; Kairuku waitaki: G, H. Credit: JVP
Phylogenetic tree of penguins. Bold sections of each line show the age range of each penguin. Reconstructions of penguin species from New Zealand include: A, Sequiwaimanu rosieae; B, Platydyptes novaezealandiae; C, Eudyptes atatu; D, Kairuku waewaeroa; E, Eudyptes chrysocome; F, Spheniscus magellanicus; G, Pygoscelys adeliae; H, Aptenodytes patagonicus. Credit: JVP
Reconstruction of Kairuku waewaeroa* by lead author Simone Giovanardi. *Not shown arm wrestling.