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. 2008 Dec 12;364(1518):807–819. doi: 10.1098/rstb.2008.0257

Table 2.

Evolutionary stability criteria for pure strategies of either target type.

strategy of type 1 individuals strategy of type 2 individuals stability criteria biological effect
play always ωlow (plow=1) play always ωlow (qlow=1) never stable
play always ωlow (plow=1) play always ωmedium (qmedium=1) never stable
play always ωlow (plow=1) play always ωhigh (qhigh=1) ESS, if B2 (type 1)<B3 (type 1) and B3(type1)>1+(1.2t/(1+t))·B2(type1) type 2 leads; mixed groups move cohesively to target 2
play always ωmedium (pmedium=1) play always ωlow (qlow=1) never stable
play always ωmedium (pmedium=1) play always ωmedium (qmedium=1) ESS, if B3 (type 1)>5 and B3 (type2)>5 equally shared decision; majority leads cohesive group
play always ωmedium (pmedium=1) play always ωhigh (qhigh=1) ESS, if B2 (type 1)>B3 (type 1); B3(type1)>((1+t+1.6tB2(type1))/(1+0.6t)) and B3 (type 2)<5 type 2 leads mixed groups towards target 2; some group fragmentation, thus, partial segregation
play always ωhigh (phigh=1) play always ωlow (qlow=1) ESS, if B2 (type 2)<B3 (type 2) and B3(type2)>1+(1.2(1t)/(1+(1t)))·B2(type2) type 1 leads; mixed groups move cohesively to target 1
play always ωhigh (phigh=1) play always ωmedium (qmedium=1) ESS, if B2 (type 2)>B3 (type 2); B3(type2)>((2t+1.6(1t)B2(type2))/(1.60.6t)) and B3 (type 1)<5 type 1 leads mixed groups towards target 1; some group fragmentation, thus, partial segregation
play always ωhigh (phigh=1) play always ωhigh (qhigh=1) ESS, if B3(type1)<1 and B3(type 2)<1 complete segregation of the two types