Perhaps From Today We Know How Aliens Are Made
The primordial Earth and the organisms that inhabited it could make us recognize life on another planets.
The early Earth was very different from the one we know now. It was an oceanic planet, which did not have an ozone layer that blocked solar radiation. As a result, bacteria and single-celled organisms (called archaea) have developed rhodopsins, proteins with the ability to transform sunlight into energy, using them to power cellular processes.
“Life as we know it is an expression as much of the conditions of our planet as it is of life itself. We resurrected ancient DNA sequences of a molecule and this allowed us to connect to the biology and environment of the past, ”said Betul Kacar, astrobiologist and study leader at the University of Wisconsin-Madison.
“It’s like taking the DNA of many grandchildren to reproduce the DNA of their grandparents. It’s just not the grandparents, but the little things that lived billions of years ago, all over the world, “said study co-author Edward Schwieterman astrobiologist.
Understanding how life has adapted to such an environment and reconstructing its evolutionary path backwards can help us imagine life on planets that have a different conformation and atmosphere from ours. Recognizing alien life is a more complex job than you can imagine.