Tinajas, Triops, and the Tenacity of Life in the Extreme

Eight years ago, when I was seven years old, my father and I spent two days and nights camping and stargazing in the arid Big Bend National Park - a place extremely unsuitable for contemporary human habitation. In the day, the land is scalding-hot, but when night falls, temperatures plummet without solar replenishment. Such an environment is not conducive to the permanent collection of surface water, so rivers and streams are rare, and any exposed ponds are fleeting. Amazingly, life not only persists but thrives. The park, among similar environments in the North American Southwest, is home to beautiful and complex ecosystems. Specifically, they are inhabited by communities of durable and hardy organisms called extremophiles (‘extreme-loving’), and they are the cornerstone of my field of interest: Astrobiology.

Personally, I interpret astrobiology as the study of life in a cosmic context. However, my definition does not give it proper credit, as astrobiology is too interdisciplinary to be put into a few words. A large part of astrobiology is looking for other life. It continues to be elusive partly because clues of its existence are sparse. So, scientists use Earth organisms as analogs for other life to help us know where and what to search for. Extremophiles, like those that I encountered in Big Bend, are particularly ideal for this purpose because the majority of extraterrestrial environments are ‘extreme’ relative to the biomes of Earth, such as the bone-chilling deserts of Mars or the noxious atmosphere of Venus.