Is it possible that we're alone in the Universe?

I would tend to think that there are many forms of life in the universe. It would be arrogant to ume that all life, being it's micro or intelligent or dominate is like us; breathing an Nitrogen-Oxygen atmosphere or walk upright or talk like we do ect you get the picture. I used to compare Earth to that one snowflake. No two snowflakes are alike. The same could apply to Earth but that is then uming that life takes hold only on planets like earth. If you were able to go back to the time life started on earth, you wouldn't survive very long. The the basic elements of life were able to adapt to its environment until it became what we are today.