|
gptkb:Amphibia
|
pollution
|
|
gptkb:Harappan
|
climate change
|
|
gptkb:Classic_Maya
|
political instability
|
|
gptkb:Norse_settlement_in_Greenland
|
climate change
|
|
gptkb:Classic_Maya
|
gptkb:dam
|
|
gptkb:Amphibia
|
gptkb:disease
|
|
gptkb:Norse_settlement_in_Greenland
|
resource depletion
|
|
gptkb:Classic_Maya
|
environmental degradation
|
|
gptkb:Amphibia
|
climate change
|
|
gptkb:Amphibia
|
habitat loss
|
|
gptkb:Hohokam_people
|
flooding
|
|
gptkb:Late_Harappan_phase
|
climate change
|
|
gptkb:Harappan
|
decline in trade
|
|
gptkb:Late_Harappan_phase
|
river shifts
|
|
gptkb:Hohokam_people
|
social upheaval
|
|
gptkb:Late_Harappan_phase
|
possible invasions
|
|
gptkb:Norse_settlement_in_Greenland
|
isolation
|
|
gptkb:Harappan
|
river shifts
|
|
gptkb:Norse_settlement_in_Greenland
|
conflict with Inuit
|
|
gptkb:Hohokam_people
|
gptkb:dam
|