Origin of Life: From dirt to humans

By Lance Braud.
How did life on Earth begin? How did the inanimate elements come together to form something new that can take in the resources it needs to reproduce? How did we go from dirt, water, and air, to snakes, birds, and humans? Nobody knows. But scientists are closing in on the likely scenarios. It crosses academic disciplines and is still hotly debated. Given the building blocks of life (carbs, lipids, proteins, and nucleic acids), how did they first come together to form something that was alive? Or as Chris Shelley, chemistry and biology instructor at BCC, says, “How did they assemble into a cell: to go from abiotic to biotic?” The problem with these questions is that there is not much fossil evidence to work from. And since we haven’t invented time travel yet, there is no way to know how life started four million years ago. Scientists do have some viable theories though. Combining our knowledge of the Earth’s past geology, chemical and biological processes, evolutionary principles, and enormous computer simulations, scientists think life might have evolved from an “RNA world.” The RNA World hypothesis says that before there was DNA