- The insistence by critics on groups being disjoint was mistaken - groups could still be targets of selection even if they overlapped.
- Kin selection was actually a type of group selection - acting on family groups.
- Reciprocal altruism was actually a type of group selection - involving small groups of reciprocators.
- Some major evolutionary transitions showed group selection in action - today's organisms were once yesterday's groups.
- Group selection had firm mathematical foundations - in the form of the Price equation.
- Laboratory experiments on group selection showed that it was potentially
a powerful force.
- There are circumstances where between-group migration was very low - for
example with parasites and symbiotes that spent most of their time inside
- Group selection explained altruism, religion, senescence, sexual recombination - etc.
- The idea that between-group variation would be destroyed by migration and/or within-group selection was wrong - since substantial between group variation could be observed empirically - for example in a species such as our own.
- The idea that groups are not replicators - and so aren't a valid "level of selection" - was bunk.
- The widespread 50:50 sex ratio was not an argument against group selection for that trait - group selection could easily favour a 50:50 sex ratio.