55,000-year-old 'urine layers' used to track climate change
Getting your hands dirty for scienceThere are many ways for scientists to look back through time. Ice cores, tree rings, sediment layers, carbon-dating, fossils, etc. Most of those we've heard plenty about, but who here has heard of studying urine layers? Indeed, it turns out that dried out layers of urine from a small African mammal, the Rock Hyrax, can be used to study our planet's changing climate.
But what makes dried Rock Hyrax urine different and scientifically useful? It's because the small social animal forms communities that live in the same rock fissures for very long periods of time, and they use the same place to pee every day. Parents teach the young where to go, and that's what they do, over and over again, for centuries and millenium in certain cases (one nest in South Africa had about 55,000 years of accumulated urine -- yuck).
"The crucial point is that hyrax urine – which is thick and viscous and dries quickly – contains pollen, bits of leaves, grasses, and gas bubbles that provide a clear picture of the climate at the time.
"Once we have found a good layer of solid urine, we dig out samples and remove them for study. We are taking the piss, quite literally – and it is proving to be a highly effective way to study how climate changes have affected local environments." (source)
Data from this project has already shown how the region's climate has changed and been affected by other climactic events taking place as far as the planet's poles.
"There were several events not long after the end of the last Ice Age when there were dramatic drops in temperature in the Arctic. These were due to great lakes of melted ice water bursting into the ocean.
"They had a huge local impact in northern Europe but we did not know how the rest of the planet was affected. Thanks to rock hyrax urine from the period, we have an answer. There was significant cooling in South Africa, and presumably the rest of the planet, at the time." (source)
This is yet one more data point to help us better understand our planet's climate and what we're doing to it. This is just one of many, many studies, but it highlights how clever scientists can be about finding climatic clues from the past.