Table 2.

Descriptive statistics of behavioural variables in the Przewalski horse (Equus ferus przewalskii) and domestic horse (Equus caballus)

Species/group	Yawning		Affiliative behaviour		Defensive interactions		Aggressive interactions
	Mean ± SD	Median [Q1; Q3]	Mean ± SD	Median [Q1; Q3]	Mean ± SD	Median [Q1; Q3]	Mean ± SD	Median [Q1; Q3]
Przewalski horses	0.99 ± 0.89	0.60 [0.20; 1.30]	9.70 ± 2.99	8.70 [8.00; 12.00]	0.16 ± 0.14	0.11 [0.08; 0.16]	0.05 ± 0.04	0.03 [0.02; 0.07]
Bachelorsa, N = 8	1.66 ± 0.94	1.50 [1.05; 2.20]	8.66 ± 2.89	8.35 [7.30; 10.30]	0.19 ± 0.21	0.11 [0.10; 0.17]	0.09 ± 0.04	0.09 [0.06; 0.12]
Coltsb, N = 5	0.53 ± 0.38	0.50 [0.30; 0.90]	9.84 ± 4.56	12.2 [9.3; 12.6]	0.18 ± 0.10	0.16 [0.13; 0.21]	0.03 ± 0.02	0.02 [0.02; 0.03]
Filliesc, N = 6	0.53 ± 0.38	0.50 [0.30; 0.90]	9.28 ± 2.52	8.40 [7.40; 10.70]	0.10 ± 0.04	0.0 [0.07; 0.14]	0.04 ± 0.01	0.03 [0.24; 0.05]
Domestic horses	0.63 ± 0.82	0.44 [0.00; 1.11]	1.86 ± 2.26	0.66 [0.22; 5.88]	0.02 ± 0.02	0.01 [0.00; 0.06]	0.02 ± 0.02	0.02 [0.00; 0.03]
Malesd, N = 6	1.37 ± 1.08	1.22 [1.11; 1.33]	3.67 ± 2.94	4.33 [0.22; 6.44]	0.02 ± 0.02	0.01 [0.00; 0.00]	0.01 ± 0.01	0.02 [0.00; 0.02]
Marese, N = 10	0.27 ± 0.25	0.33 [0.00; 0.44]	0.64 ± 0.79	0.33 [0.22; 0.88]	0.01 ± 1.93	0.01 [0.00; 0.02]	0.03 ± 0.02	0.02 [0.01;0.04]
Geldingsf, N = 3	0.07 ± 0.12	0.0 [0.0; 0.22]	1.19 ± 0.68	1.33 [0.44; 1.77]	0.03 ± 0.03	0.02 [0.08; 0.06]	0.01 ± 0.01	0.02 [0.08; 0.06]

^aAdult intact males in the male-only group

^bIntact males of less than 1 year old

^cFemales of less than 2 years old

^dSexually mature males

^eSexually mature females

^fCastrated males