Recently, scholars have distinguished between different kinds of diaspora, based on its causes such as colonialism, trade or labor migrations, or by the kind of social coherence within the diaspora community and its ties to the ancestral lands. Some diaspora communities maintain strong political ties with their homeland. Other qualities that may be typical of many diasporas are thoughts of return, keeping ties back home (country of origin) relationships with other communities in the diaspora, and lack of full integration into the host countries. Diasporas often maintain ties to the country of their historical affiliation and influence the policies of the country where they are located.