[beeflet]

Do you think group selection applies to eusocial species such as bees? It must. If so, imagine a species that is incrementally less social than eusocial. Unless there is some threshold degree of sociality required for group selection, then there clearly some level of group selection occurs for other animals (whether or not it's a major effect)

[shellfishgene]

This is usually explained by kin selection, which is different from group selection. I'm not an expert on either though.