Dovidio and his colleagues argue that cooperation has an especially positive impact when people are able to keep their ingroup identities intact. people working on a task have relatively low self-esteem. it leads people to define a new, inclusive group. groups are relatively independent.

According to the argument posed by Dovidio and his colleagues, cooperation has an especially positive impact when it leads people to define a new, inclusive group. An inclusive group makes room to accommodate new members while an exclusive group seeks to limit membership to those who can meet some strict requirements of who have a special status.

giant impact theory - the moon was formed from the collision between earth and another mars-sized body.

colliding planetesimals hypothesis - the moon was formed from the same cloud of material as earth.

capture hypothesis - the moon was locked into orbit by earths gravity as it was passing by it.

accretion hypothesis - the moon was formed from collisions and combining of planetesimals.

i think this is right, if not and you know better let me know.