Two science headlines caught my attention this week that highlight how little we still know about the habitats and diversity of living things and how exciting new discoveries can be. For starters, scientists exploring the Cave of Crystals in a mine in Chihuahua, Mexico think they have discovered a type of microorganism that may have been lying dormant for tens of thousands of years. It is previously unknown to science and has clever metabolic strategies that allow it to use materials such as iron and sulfur as its resources. For beautiful pictures and videos of the mine and the crystals, as well as a nice discussion of the challenges of this type of research endeavor, check out this description of the research from National Geographic: http://news.nationalgeographic.com/2017/02/crystal-caves-mine-microbes-mexico-boston-aaas-aliens-science/
Peer review and publication of the results in a scientific journal and further study and verification will clearly be required to understand this novel addition to our growing list of microbial neighbors. We have only begun to scratch the surface of understanding the majority of living things on the planet, because they’re microscopic, and so few of them can be cultured in the lab (like these cave dwellers). But our previous efforts to “mine” and explore what appear to be uncharitable places to live have turned up other surprising residents in the past.
For example, this photo shows a species of microbe named Thermus aquaticus. It lives in hot springs, where the temperature is near the boiling point of water. Humans gained some practical benefit for our own society after its discovery: the enzymes of this microbe function at the high temperatures. One of them, which is responsible for copying the microbe’s DNA, can be purified and used to replicate DNA samples that humans collect and study in the lab, from crime scenes and paternity testing, or for basic lab science that helps us understand how DNA works in general. (See this link for more on PCR: https://www.genome.gov/10000207/polymerase-chain-reaction-pcr-fact-sheet/)
It thus has been clear to scientists that in order to understand the complex collection of species on Earth, we need to branch out in terms of where we look: hot springs, permafrost, caves and deep sea vents, the heights of mountains…the opportunities are endless. But for all of its diverse habitats, the “big blue marble” we call home contains the only hospitable island of life we’ve located so far in the universe.
(Photo credit: NASA images-assets.nasa.gov/image/PIA18033/PIA18033~orig.jpg)
Recently, new technology has accelerated the search for life on our nearest neighbors: the planets in our solar system. Astrobiologists (I love that this type of scientist exists!) have been conducting experiments to consider what conditions might be like on other planets, moons, etc. and what types of living things we might expect to find there. We have learned so much about microbial diversity here on Earth, and so we take photos, and probe the soil, and examine the atmosphere, and look for water elsewhere and wonder if we will find we’re not alone in the universe.
The second news story of the week looks at one angle of these continuting efforts, on Europa, one of Jupiter’s moons. Europa seems to have oceans made of water and fascinating topology and geologic processes that might create conditions suitable for microbial life. Check out this link for more on the Europa Multiple Flyby Mission slated for the next decade, and how it could change our perceptions of life and our study of our solar system: https://www.scientificamerican.com/article/europa-mission-heralds-sea-change-in-the-search-for-alien-life-video/
Photo credit: NASA. https://images.nasa.gov/#/details-PIA20025.html
I love when different areas of science intersect to help us truly understand our place in the universe in more detail. Financial support for projects like these gets us closer to understanding the workings of the natural world, and sometimes yields surprising practical benefits. I can’t wait to see what the dedicated microbiologists and astrobiologists turn up next as we fill in the pages of the book of life, on Earth and perhaps beyond!