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Flashcards in Natural History Deck (22):

castrated male=
young male/female=

foal (m=colt, f=filly)


height measured in

pony less than 14.2 hands,
largest horse is clydesdale at 17-18 hands


breed types

pony, clydesdale, quarterhorse, przewalski, shetland pony



88km/hr, average 72 km/hr


life expectancy

20 years in wild (based on przewalski), and 25-30 in captivity


reproductive cycle

seasonally polyestrous; mate and foal in late sprind/midsummer when daylight is long
-unlikely to breed past 20


northern breeds

cold bloods/trotters/drafts are heavier built, deep bodies, short legs, small ears, large heads, thick coats
breeds adaptive for energy conservation in cold climates:shetland pony, haflinger, clydesdale


southern breeds

aka hotbloods/hallopers
-long slender legs, fine coats, smaller heads and larger ears
-fast, highly reactice and enduring
-adapted to aid heat dissipation?
ie. persian/arabian, thoroughbreds
warmbloods are mix of hot(south) and cold (north)



open plains or mountains but can adapt
-ie marshlands to woodlands
-loyal to undefended home ranges and make use of core areas



preferential grazers but can browse on forbs, sedges, shrubs, and tress
diets may change seasonally
-feral and free-range eat up to 6 hours per day (60-70% of day)


defecation behaviour

-differs btw confined and free-range
-captive: latrine and grazing areas for parasite avoidance
-free: defecate indiscriminately, except for marking behaviour
-latrine behaviour appears due to domestication and selection for this behaviour in high density


social organizations

1. domestic donkey, zebra, and wild ass
2. domestic/wild horse, and mountain zebra


domestic donkey, grevy's zebran, and wild ass social organization

-territorial males
-adult do not form lasting bonds
-females range over territory of several males while accepting mates
-sub-adult males disperse to join/form roaming bachelor groups
-adaption to predictable but marginal desert conditions?


domestic/przewalski horse, mountain zebra social

stable, long lasting non-territorial family band
-subadult males leave to join/form bachelor groups
-subadult females join/form new harems
-adaption to UNpredictable envrionment and changing but constant food supply may prompt migration


flexible behaviour

ferals of shalkeford banks, North carolina show BOTH social organizations
-half island access to limited resources is important that population adopted territoriality
-half not limited in resources so not territorial


stable family bands

band=group with stable adult membership and pre-dispersal offspring
2-30 members
members: 1 to several unrelated adult mares, 1-a few stallions and immatures offsprings 1-3 years old
-bands may temporarily group with other bands, esp in winter when predation risk increases


multiple stallion bands

1-5 stallions
may have negative consequences to mare like greater parasite load, poorer body condition, reduced fecundity due to stallion harassment
mare may however solicit more than one stallion


social behaviour: dyadic bonds

adults form dyadic bonds (mare-mare, stallion-mare, etc): spacial proximity and reciprocal positive interactions like grooming


dominance hierarchies

stable and linear, though sometimes they reverse or form triangles
-once established they are maintained
-may provide priority access to food and breeding
-stallions not always highest rank
social behaviour minimizes conflict and keeps group stable
being in groups reduces predation


agonistic behaviour

less frequent than friendly behaviour
-serious injuries are rare
-most common aggressions are low intensity displacements (15%), threats to bite (41%), and threats to kick (20%)
-rank associtaed with age, longevity in band, and body weight
-high ranked males more involved in agnoistic behaviour, but not often the recipient, foals the least involved
-foal rank order before and after weaming positively correlated with rank order of dams


foals and social development

long term relationship with dam
-before and after birth mare separates from group, bond formed with foal
-2-3 weeks will start interacting with other foals
6 months 40% time with dams
-weaning occurs before birth of next foal (approx 7 months) but maintains close relationship
-social interactions with others are critical for social development of foals


dispersal of young adults

at sexual maturity; 2-3 years old
-males form bachelor groups 1-15 males, sometimes under older stallions
-home ranges of bands and bach males overlap
-groups are not stable associations
aquires females at 5-6 years old
females are 1 and 2 year old mares dispersing from natal bands
-mares disperse non-randomly, join harmes with at least 2 other mares
-prefer familiar females but not males, avoiding relate males to keep inbreeding low
-no costs to leaving for mares