Species-level divergences in multiple functional traits between the two endemic subspecies of Blue Chaffinches Fringilla teydea in Canary Islands

Table 8 Sperm morphometrics of ssp. teydea and ssp. polatzeki of the Blue Chaffinch Fringilla teydea

Sperm trait	teydea (Tenerife)	polatzeki (Gran Canaria)	Test of difference between means	Test of difference between variances	Effect size Cohen’s d
Head length (μm)	17.05 ± 0.70 (22)	18.01 ± 0.60 (11)	t ₃₁ = −3.86, P < 0.001	F-ratio = 1.34, P = 0.65	−1.47
Midpiece length (μm)	224.10 ± 5.78 (22)	232.92 ± 4.41 (11)	t ₃₁ = −4.44, P < 0.001	F-ratio = 1.71, P = 0.38	−1.69
Tail length (μm)	13.63 ± 5.21 (22)	12.49 ± 4.41 (11)	t ₃₁ = 0.60, P = 0.55	F-ratio = 1.16, P = 0.84	0.23
Total sperm length (μm)	254.75 ± 3.74 (43)	263.42 ± 3.46 (11)	t ₅₂ = −6.96, P < 0.001	F-ratio = 1.17, P = 0.83	−2.40
CV_wm total length (%)	1.24 ± 0.36 (43)	1.06 ± 0.26 (10)	t ₅₁ = 1.44, P = 0.16	F-ratio = 1.88, P = 0.31	0.60
CV_bm of mean total length (%)^a	1.48	1.34

^aAdjusted for variation in sample size (N) by the formula CV_bm = SD/mean × 100 × (1+ 1/4 N)
Ten sperm cells were measured per male, except for one teydea and two polatzeki with very few sperm cells in the sampled ejaculate. Mean values are given with their ± SD (N)

ISSN: 2056-3132