Table 1.

Summary of results testing for differences between various groups.

	Measure		Year		Spawn		Pacific		West Atlantic		East Atlantic		Pop
	F	P	t	P	F	P	F	P	F	P	F	P	F	P
HL	0.55	0.46	1.22	0.2287	2.32	0.09777	8.27	<0.0001	11.23	<0.0001	44.47	<0.0001	36.48	<0.0001
HW	0.46	0.50	3.88	0.0005	7.31	0.00097	5.4	<0.0001	25.76, 9.13	<0.0001, <0.0001	15.82	<0.0001	23.61	<0.0001
AL	0.04	0.84	-0.56	0.5765	0.61	0.61723	8.86	<0.0001	10.98	<0.0001	4.51	0.0008	8.43	0.0005
TOTAL	0.00	0.98	-0.53	0.598	0.95	0.42989	6.79	<0.0001	10.36	<0.0001	4.4	0.001	2.9	0.0612
MA	3.62	0.06	2.45	0.0194	4.84	0.008	13.23	<0.0001	12.5	<0.0001	0.76	0.5789	8.15	<0.0001

Results for trait differences between measurement events (Measure), 2006 and 2007 West Atlantic sperm traits (Year), among spawnings within an individual (Spawn), among individuals within populations (Pacific, West Atlantic, East Atlantic), and among populations (Pop). For HW, individual differences within West Atlantic reported for 2006 and 2007, respectively, and Pop reflects separate accounting for the West Atlantic population by year. Sperm traits are head length (HL), head width (HW), axoneme length (AL), total length (TOTAL), midpiece area (MA).