Table 1.

Flexibility and constraint in response to ecological stressors (ungulate studies).

references	species	flexible trait(s)	constraint(s)	stressor/response
Valeix et al. [53,54] Valls-Fox et al. [55]	giraffe (Giraffa camelopardalis); impala (Aepyceros melampus), greater kudu (Tragelaphus strepsiceros), waterbuck, (Kobus ellipsiprymnus), blue wildebeest (Connochaetes taurinus), common zebra (Equus burchelli), roan antelope (Hippotragus equinus), sable antelope (Hippotragus niger), cape buffalo (Syncerus caffer) and warthog (Phacochoerus africanus) African elephant (Loxodonta Africana), cape buffalo (Syncerus caffer)	day–night temporal activity pattern/tolerance of interspecies competition/antipredator behaviour	water dependency	dry-season conditions alter by-species patterns of sensitivity to interference competition, antipredator behaviour and day–night time-shifting as water dependency increases
Crosmary et al. [56]	impala (Aepyceros melampus), greater kudu (Tragelaphus strepsiceros), sable antelope (Hippotragus niger)	day–night temporal activity pattern	water dependency	under anthropogenic hunting pressure, differential vulnerability to natural sympatric predators mediates flexible time-shifting behaviour in three ungulate species
Jin & Ma [57]; Luo et al. [58]	Mongolian gazelle (Procapra gutturosa)	habitat selection/antipredator behaviour	feeding constraints	winter conditions reduce flexible, predator-sensitive habitat selection as feeding constraint increases
de Silva et al. [59,60] Wittemayer et al. [61]	Asian elephant (Elephas maximus), African elephant (Loxodonta africana) African elephant (Loxodonta africana)	social networks/grouping	feeding constraints	under conditions of more uniform and abundant forage, Asian elephants show more fluid grouping patterns and hierarchical structuring than do African elephants
Lone et al. [62]	roe deer (Capreolus capreolus)	day–night temporal activity pattern/habitat selection	feeding constraints	winter conditions reduce flexible, predator sensitive day–night time-shifting and habitat selection as feeding constraint increases
Loehr et al. [63]	Stone's sheep (Ovis dalli stonei), thinhorn sheep (O. dalli), bighorn sheep (O. canadensis)	inherited behavioural traits		a subspecies descended from hybrids shows variable expression of phenotypic and behavioural traits inherited from the parent species and subsequently refined by selection
Endicott-Davies et al. [64]	red deer (Cervus elaphus), ¾ red deer × ¼ Père David's deer (Elaphurus davidianus) hybrids	inherited behavioural traits		hybrid calves show intermediate inherited behavioural traits