Table 1 Results of likelihood ratio test of hypotheses of positive selection on LAEWC trait shift. The result shows that most LAEWC related genes were not positively selected during the trait shift of LAEWC except theCER1under the hypothesis 1 (positive selection independently acted on the gain of LAEWC)

Hypothesis^a	Gene	lnL₀^b	lnL_A^b	2ΔL	df	P
Hypothesis 1	CER1	− 2969.327	− 2965.950	6.754	1	0.009
	CER3	− 2923.209	−2923.041	0.338	1	0.561
	CER5	− 3516.913	−3516.577	0.670	1	0.413
	CER7	−2009.028	−2008.247	1.561	1	0.211
Hypothesis 2	CER1	−2969.327	−2969.322	0.010	1	0.919
	CER3	−2923.209	−2923.133	0.153	1	0.696
	CER5	−3516.913	−3516.908	0.010	1	0.921
	CER7	−2009.028	−2007.660	2.735	1	0.098
Hypothesis 3	CER1	−2969.327	− 2967.980	2.694	2	0.260
	CER3	−2923.209	−2923.210	0	2	NA
	CER5	−3516.913	−3516.913	0	2	1
	CER7	−2009.028	−2007.662	2.731	2	0.255

^aHypothesis 1: Fig.1a;假设2:无花果。1b;Hypothesis 3: Fig.1c
^blnL₀: natural logarithm of the likelihood of null model; lnL_A: natural logarithm of the likelihood of alternative model