What processes has equine evolution been through?
Adaptation
- those with better suited genes to the environment are more likely to survive
- Produce more offspring
- less adapted individuals die out
- future of species will have similar feature I the successful individuals
Natural selection
- those which have desirable trait are more likely to survive
- eg flight or fight response. Those who stay to beat up predator will likely die compared to those who run to the hills
Competition
- the stronger and cleverer will win
Variation
- there will be differences in every individual and some will naturally survive better
- eg short legged horse can’t reach food sources as easily as those with longer legs.
Behaviour is…
- a phenotypic feature
- occurs in response to interactions
- interaction can be between the environment or other individuals
Why so horse have long legs?
- heritable trait
- not only evolved for escaping predators although it helps
- longer legs means more muscle power
- horse have reached the optimum length
Importance and expression if physiology. What’s involved?
Example galloping
Causation
- nerve impulses from brain to muscle to initiate galloping
Function
- to RUN AWAAAAAY (from predators)
Ontogeny
- foals learns to coordinate standing and running to escape predator
Phylogeny
- those which gallop fastest and furthest (or gallop at all) from predators will survive
How does a horse communicate?
- overt and subtle signals
- composite signals to accompany other signals (zebra face when in oestrus)
Metacommunication
- preliminary signals which define the meaning of those that follow.
- eg nip to initiate play
What are the four communication types?
Auditory
Tactile
Chemical
Visual
What acoustic signals are use in horse communication?
Neighs and whines
- demonstrate presence to others
Nickers
- signals approach of another
Squeals
- defensive and threatening greeting
Groans
- tiredness and discomfort
Roars and screams
- extreme sexual arousal
- signal physicals violence
- used when subtle signals are ignored
Short snorts
- alarm call
What is altruism?
- a selfless act
- demonstrates concern of others
- eg mare protecting foal OR healthy horse protecting injured individual
- can result in death o either or all involved
- alters natural selection
Describe stages of horse development between 0-2 years.
Neonatal 0-2hours
- coordinating limbs for standing and walking to suckle
Transitional 0-2weeks
- senses are refined
- foal will be jumpy as a result of getting use to senses
Socialisation 4-12 weeks
- begin allogrooming
- Communicate with others
- jaw snapping
Juvenile 12weeks - 2 years
- finding place in the herd
- learning adult behaviour/ communication
- active play
What types of chemical signals are there?
Skin secretions Breath Faeces Urine Saliva
Give and example of when chemical signals are used.
- A mare will signal reproductive state through urine signals
- foals will swish tail to send chemicals signals toward the mate.
What forms of identification can a horse detect from chemical signals ?
- Sex
- Age
- Development/growth stage
- Maturity
- Physical state
- Sexual arousal
- Coordination and spacing of individuals
- Navigation and orientation
How does a horse detect chemical signals?
- uses flehmen response
- this focuses chemicals to the vomeronasal organ
- vomeronasal Organ located behind upper lip
Describe four horse herd grouping types
- Lone stallion
- stallion as harem
- bachelor band
- mixed non-mating juvenile band
What tactile signals are used between horses??
Allogrooming
- Horses prefer to groom each other rathe than themselves
- reduces heart rate
- lasts <3 minutes
- horse will ask to initiate grooming by dropping bottom lip and holding down ears
- dominant horse will break up grooming
Large groups
- show preferred grooming groups
Small groups
- groom everyone
What visual signals are used between horses?
- Horses have very good eyesight
- Use body language to signal
- eg ears down, tail swish, dropping bottom lip
