Video Transcript
Edmund: Our planet is one of billions in the universe. But there’s one thing that makes it uniquely more interesting than any planet we’ve ever discovered and that is… LIFE! Crawling, flying, walking, talking, breathing, swimming, snoring, photosynthesizing, growing… life.
Life can be small like the nanoarchaeum equitans. A species of microbe that is around 200 nanometers in diameter that was discovered in hydrothermal vents off the coast of Iceland. Life can also be large like the blue whale, which most people think of as the largest animal. If we broaden it to not include just the largest animal but the largest organism on earth, that has to be the aspen tree colony known as “Pando”.
From the air, pando looks like a forest of individual trees. But genetic studies found that the 100 acres of trees all had the same genetic markers. This proves that it isn’t many trees, but one massive plant with a single underground root system growing many trees out of it. So it’s all one tree! This makes Pando technically the heaviest known organism and the oldest, estimated to be several thousand years old.
Nicole: I’m Nicole Deak. I am a PhD in biology, and I am currently living in Chicago.
As far as I can remember as a child, just really loving nature. And it came out and all sorts of ways, you know, mud pies, collecting snails and slugs, and what I called slug farms, collecting roly polies, watching ants. So I just had this general overall love of nature.
Still what keeps me in is the same wonder that I had as a child. I still love organisms. I love the environment. I love the natural world and it fascinates me.
Life is so complicated and complex and beautiful, that it really supports that.
Edmund: Life is rather mysterious. The word biology literally means the study of life. The earliest known life on earth existed over 3.5 billion years ago. So you would think scientists could agree on what life… “is.” But there are hundreds of definitions of life and scientists don’t seem to have a clear consensus on the definition of “life.”
Nicole: What makes something alive? If something is alive and then we consider it dead, we don’t know exactly what makes that difference from a thing being alive versus when it has died?
Edmund: James Gould, evolutionary biologist from Princeton, said “most dictionaries define life as the property that distinguishes the living from the dead, and define dead as being deprived of life. These singularly circular and unsatisfactory definitions give us no clue to what we have in common with protozoans and plants.”
Scientists are looking for life farther into the universe than ever before. But what qualifies as “life” in outer space? NASA defines “life” as, “a self-sustaining chemical system capable of Darwinian evolution.”
There is a mystery to what makes something truly “alive” and what happens when a living thing dies. But life also makes us wonder, where does it all come from?
One idea that sounds funny to us now, was believed until the 19th century. Aristotle and other ancient Greek philosophers held the spontaneous generation theory of life. They believed that living creatures could spontaneously appear out of other substances. This view was held for centuries. People believed mice could be created and appear out of garbage. Fleas could appear out of sawdust. And maggots spontaneously appear on rotting meat.
By the 19th century scientists such as Louis Pasteur and others performed experiments disproving the theory of spontaneous generation.
Nicole: I think a lot of people assume that scientists or biologists or any other kinds of scientists, you know, that they have the answers. And they have some answers! You know, we do have some answers. I really have to give credit to human ingenuity and intelligence, but at the same time, there’s so much more.
Edmund: Now, there are several theories about the first origin of life. It’s incredible to think of the way trillions of life forms on earth are so intertwined and dependent on each other today. Human life depends on living things to survive and still so much of it is a mystery.
But that mystery of life leaves us asking: where did the first life come from? What is the beginning of all of creation?
