Each child when born could have a pond assigned to them. Their lifetime job could be to describe its features and inhabitants - algae flora, microbes and fauna, etch, whatever they want to investigate - to go into a world atlas of ponds and pond life by the end of their (the person's) days, however many days they may be alive. That will give everyone a purpose in life if they want one at some stage of their life - which will be the advancement of the sum knowledge of the world for the benefit of humanity (or vice versa if you like) - if they choose to take it up. Or not.