“My life has but one object; I am writing the history of penguins.” – Anatole France, Penguin Island
A column by penguin nerd since third grade and aspiring penguinologist Alexandra Kluzak
The delightfully cute and fluffy creatures known as penguins can waddle, shake, shimmy — as my favorite “congratulations” and “happy birthday” GIFs display — dive, and zoom through the water with impressive speed. In the 2006 animated film Happy Feet, they even sing and dance (on ice and into our hearts). But, despite what their general physical prowess and classification as birds would suggest, they cannot fly. A long history of evolution traces the transformation of the flying seabird into a proud denizen of the sea.
The nineteen species of penguins which inhabit a broad swath of the Southern Hemisphere share a common ancestor, an albatross-like bird which lived in the South Pacific islands approximately sixty million years ago (1). Like the puffin, this ancestor could both fly and dive, but subsequent generations lost the former ability as the diving ability was favored in an aquatic habitat (1). Wings morphed into propellers composed of flattened, fused bones overlaid with strong bicep-like muscles (2). Twenty-two million years ago, a clockwise ocean current running near the South Pole carried the first penguins across the region where they laid claim to Antarctica (3). Ten million years after that, the same current deposited the creatures on the shores of Africa and South America, where they can still be found today (3).
Each of these species evolved differently, but retained the defining feature of a penguin: the endearing black and white feather “tuxedo.” Whichever climate they have come to inhabit, penguin species are well served by this adaptation, especially when they are underwater. Predators swimming below them must perform the difficult task of distinguishing the penguins’ white bellies from the light hues created by the sun, while predators swimming above them have similar difficulty distinguishing their black backs from the darkness of the ocean (2).
Though they may share the same basic coloring, penguin species vary in many of their other traits, because they developed unique genetic adaptations to survive their respective climates. For example, the Emperor penguin has an extra layer of feathers, a large reserve of fat, and a small beak and flippers to prevent heat loss in the temperatures as low as -50 degrees celsius it bears in Antarctica (4). The Galapagos penguin, which faces the opposite challenge of extreme heat in its Galapagos Island environment, has fewer feathers, less body fat, and areas of bare skin to deflect the sun from its body (5). Contrary to popular belief, most penguin species do not live in freezing environments like the Emperor penguin. Eleven, in fact, live in tropical climates like the Galapagos penguin (5).
Long and divergent histories of evolution resulted in the great diversity of penguins, which is a blessing to those who delight in cuteness and admire adaptability and positivity in extreme circumstances.
- (2022, July 20) Scientists uncover the evolution of penguins. Channel News Asia. Retrieved from https://www.channelnewsasia.com/world/scientists-uncover-evolution-penguins-2821956.
- Hall, D. Penguins Introduction. Smithsonian. Retrieved from
- https://ocean.si.edu/ocean-life/seabirds/penguins#:~:text=Roughly%2066%20million%20years%20ago,common%20ancestor%20of%20all%20penguins.
- Intagliata, C. (2020, August 18) National Public Radio. Retrieved from https://www.npr.org/2020/08/18/903593291/the-evolutionary-history-of-penguins-is-far-from-black-and-white
- 10 facts about emperor penguins. World Wildlife Fund. Retrieved from https://www.wwf.org.uk/learn/fascinating-facts/emperor-penguins#:~:text=Emperors%20are%20uniquely%20adapted%20to,penguins%20to%20prevent%20heat%20loss.
- Swindlehurst, D. (2015, November 13) How the Galapagos penguin adapted to life in the sun. Galapagos Conservation Trust. Retrieved from https://galapagosconservation.org.uk/how-the-galapagos-penguin-adapted-to-life-in-the-sun/.
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