When I considered how I might become a fossil, I mostly thought about the environment I’d have to be entombed in. Desert. Seafloor. Lakebed. These are all pretty typical burial spots that rely on sand, mud, or silt. But I hadn’t yet heard of an even better option when I wrote that piece. As it turns out, entombment in penguin guano is a great way to preserve bodies for thousands of years.
Not just any penguins will do. It has to be Adélie penguins. These amphibious Antarctic birds breed on solid ground – not ice – and carefully select pebbles to create their nests. That’s what traps their guano. As the penguins create a crap cap on their breeding ground, they preserve the remains of their meals and their deceased neighbors within a mix of sand, pebbles, and guano. And while they start off as relatively dark at first, the deep layers of penguin leavings eventually turn pink from the krill in the Adélie diet. In some places, these easily-identifiable layers are over three feet thick.
The Russian biologist E.E. Syroechkovsky named these bird-created deposits “ornithogenic soils” in 1959, and, as University of North Carolina ecologist Steven Emslie and coauthors review in a new paper, the bird dirt has become a treasure trove of information about life since the Ice Age.
While chinstrap and gentoo penguins also create ornithogenic soils, their records pale in comparison to that of their cousin. Adélie penguins have created expansive deposits that go back over 40,000 years in some places, allowing researchers to see how the birds coped with the world’s last great expansion of ice. While Adélie penguins thrived in the Antarctic’s Ross Sea prior to 20,000 years ago, for example, they disappeared as ice overtook their breeding grounds. They only returned when warmer temperatures released their breeding grounds from ice after 18,000 years ago.
And the penguin-made fossil record preserves even finer details. In addition to squid beaks and fish “earstones” that made their way through the avian digestive system, Emslie and colleagues point out, the soils also contain the bodies and bones of the penguins themselves. Some researchers have even uncovered complete penguin “mummies” within ornithogenic soils. The cold, dry conditions at the breeding grounds kept the bird remains in excellent condition, allowing paleogeneticists to extract and study DNA from penguin populations through time. That’s not to mention the additional geochemical insights drawn from some of the fossil and subfossil remains, such as that Adélie and gentoo penguins started eating more krill about 200 years ago – right when whalers and fur trappers slaughtered many of the whales and seals in the southern seas.
Will I ever request that my earthly remains be laid bare on an Adélie penguin colony? Despite the preservation potential, probably not. I’d rather my bones wind up in a museum. But as long as I’m alive, I’ll look forward to the Ice Age details ecologists extract from penguin plop.
[Hat-tip to Jacquelyn Gill for pointing out the Emslie et al. paper to me.]
Reference:
Emslie, S., Polito, M., Brasso, R., Patterson, W., Sun, L. 2014. Ornithogenic soils and the paleoecology of pygoscelid penguins in Antarctica. Quaternary International. 352: 4-15. doi: 10.1016/j.quaint.2014.07.031
Go Further
Animals
- These 'trash fish' are among Earth's most primitive animalsThese 'trash fish' are among Earth's most primitive animals
- These photos are works of art—and the artists are bugsThese photos are works of art—and the artists are bugs
- The epic migration of a 6-foot long, 200-pound catfishThe epic migration of a 6-foot long, 200-pound catfish
- Frans de Waal, biologist who studied animal emotion, dies at 75Frans de Waal, biologist who studied animal emotion, dies at 75
Environment
- Are synthetic diamonds really better for the planet? The answer isn't clear-cut.Are synthetic diamonds really better for the planet? The answer isn't clear-cut.
- This year's cherry blossom peak bloom was a warning signThis year's cherry blossom peak bloom was a warning sign
- The U.S. just announced an asbestos ban. What took so long?The U.S. just announced an asbestos ban. What took so long?
- The most dangerous job? Inside the world of underwater weldersThe most dangerous job? Inside the world of underwater welders
- The harrowing flight that wild whooping cranes make to surviveThe harrowing flight that wild whooping cranes make to survive
History & Culture
- Meet the powerful yokai that inspired the demon king in ‘Demon Slayer’Meet the powerful yokai that inspired the demon king in ‘Demon Slayer’
- A surprising must-wear for European monarchs? Weasels.A surprising must-wear for European monarchs? Weasels.
- Meet the woman who made Polaroid into a cultural iconMeet the woman who made Polaroid into a cultural icon
- Inside the observatory that birthed modern astrophysicsInside the observatory that birthed modern astrophysics
Science
- LED light treatments for skin are trendy—but do they actually work?LED light treatments for skin are trendy—but do they actually work?
- NASA smashed an asteroid. The debris could hit Mars.NASA smashed an asteroid. The debris could hit Mars.
- Humans really can have superpowers—scientists are studying themHumans really can have superpowers—scientists are studying them
- Why engineers are concerned about aging infrastructureWhy engineers are concerned about aging infrastructure
Travel
- 2024 will be huge for astrotourism—here’s how to plan your trip2024 will be huge for astrotourism—here’s how to plan your trip
- Play and stay in the mountains of eastern Nevada
- Paid Content
Play and stay in the mountains of eastern Nevada - This couple quit the city to grow wasabi in Japan's mountainsThis couple quit the city to grow wasabi in Japan's mountains