My teacher challenged me to evaluate a scholarly article so this is what I got.
This article is about great filters one of the main topics of the Fermi paradox. Great filters are events that can wipe out species at any stage of life. The more civilization closer to our level of progression the more likely it is ahead of us. The less life there is the more likely it was behind us. We can calculate the possible amount of life around using the Drake Equation but it is only a guess not an exact number.
https://informationisbeautiful.net/visualizations/the-drake-equation/
This link leads to an interactive example of the drake equation.