Compare the flow of energy that will occur if beaker 1 is placed next to beaker 2 with the flow of energy that will occur if beaker 2 is placed next to beaker 3.

Which of the following is a reason why early living organisms on earth could not have survived on the surface? 1. the lack of an ozone layer 2. the lack of oxygen in the atmosphere 3. the fact that these organisms were single-celled