Evolution of animal behaviour part 1

• Animals all have these in common

  • Multicellular 
  • Heterotrophic 
  • Eukaryotes 
  • Tissues develop from embryotic layers 
•  

  NZ legal welfare act 1999

  • Animal means any live member of the animal kingdom that is a mammal, bird, reptile, amphibian, fish (bony or cartilaginous), octopus, squid, crab, lobster, crayfish (freshwater crayfish), any other member of the animal kingdom which is declared by the governor general does not include human being

   
• standard error calculation = standard deviation divide by the square root the sample size
• behaviour means = response to internal and external stimuli
• motor neurons control contraction, sequence, timing
• three components to a circuit = sensory input, central processing, motor output
• inhibitory = hide
• excitatory = run, attack, mate
• circuit = sensory neuron, interneuron, motor neuron
• stronger the signal the more connections of interneurons and more intense movement
• high threshold= strong stimulus needed to elicit behaviour lower probability of expressing behaviour, high energy cost
• low threshold= weaker stimulus will elicit behaviour, higher probability of expression
• proximate current causes of behaviour modulation

  • stimulus - hormones mobbing behaviour (running away)
  • other relevant information - behaviour of other animals, memory/learning, emotions, physiological state
• proximate historical causes of behaviour modulation -

  • hormonal environment
  • external environment (learning)
• pain processing

  • different receptors to tissue damage
  • feel pain before tissue damage
  • nocieption physiological system tissue damage is occurring
• pain in humans

  • ask or watch behaviour
  • factors, breed,sex, ages, location
• create emotion state of pain without nocieption (phantom)
• threshold testing - quick reflexes use more energy, rapid reflex no nocieption
• behaviour analysis

  • abnormal behaviour limp, freezing
  • interactive behaviour - stop interacting, stop drinking, eating, playing (normal)
  • frequency - shaking
• motivational trade off

  • indicate animal is weighting up different motivations
• Define animal as used within this course and as used by the NZ animal welfare act 1999

  • Animals all have these in common, multicellular, heterotrophic, Eukaryotes, Tissues develop from embryotic layers 
  • any live member of the animal kingdom that is a mammal, bird, reptile, amphibian, fish (bony or cartilaginous), octopus, squid, crab, lobster, crayfish (freshwater crayfish), any other member of the animal kingdom which is declared by the governor general does not include human being
• Proximate

  Current (short term): HOW DOES IT WORK (How do internal factors or external stimuli elicit / control behaviour) - Which physiological, hormonal, psychological mechanisms regulate expression of behaviour
• Proximate Historical

  Sometime in the past: HOW DID IT DEVELOP (In lifetime of animal, how did its behaviour arise (development / ontogeny) - What factors influence development of behaviour in animals lifetime - How do environment and individual (genetics) interact during development of behaviour - Fertilization until are born
• Ultimate Current

  Short term: WHAT IS IT FOR (What is current use of survival value of behaviour) - How does behaving this way help individual survive or reproduce in physical and social environment
• Ultimate Historical

  Sometime in the evolutionary past: HOW DID IT EVOLVE (Cause of behaviour over generations of animals) - How did behaviour arise during evolutionary history of species (Evolution / phylogeny) - What factors involved in moulding behaviour over generations - How can comparison of species help explain history - How has behaviour itself driven evolution, through mate choice - Mutations effect traits / offspring passed on into species - Fossil records to see if traits are present in extinct species and why they became extinct
• Define behaviour

  •  response to internal and external stimuli
• Explain how behaviour is generated by the nervous system

  • motor neurons control contraction, sequence, timing 
  • circuit = sensory neuron, interneuron, motor neuron 
  • inhibitory = hide 
  • Excitatory = run, attack, mate 
  • three components to a circuit = sensory input, central processing, motor output 
• Describe the three components of neural function underlying expression of behaviour that could theoretically be modified by factors such as hormones

  • three components to a circuit = sensory input, central processing, motor output 
• Explain, using the example of the gill-withdrawal reflex in Aplysia, how behaviour can be modified by changes in the activity of the nervous system

  • stronger the signal the more connections of interneurons and more intense movement 
  • high threshold= strong stimulus needed to elicit behaviour lower probability of expressing behaviour, high energy cost 
  • low threshold= weaker stimulus will elicit behaviour, higher probability of expression
• Discuss some proximate CURRENT causes of altered nervous system activity and behaviour, providing specific examples

  • stimulus - hormones mobbing behaviour (running away) 
  • other relevant information - behaviour of other animals, memory/learning, emotions, physiological state 
  • Examples: Male bird singing in certain time of year - Stags fighting  - hormones - Caterpillar - Child playing with doll (maternal instincts) and boys playing with sticks (testosterone in stages) - Snakes burrowing  - Bear hibernation 
• Proximate causes

  • Hormonal environment
  • External environment (learning)
• Bird song

  • Organised by sex hormones
  • Species specific
  • Attract mate of their species
  • Changes in interneurons and motor outputs
  • Different sex has different song circuits
  • Songs influenced by hormones during development
  • Hormonal environment during development determined by genes
  • High concentrations of testosterone during development so larger neurons and nuclei in song circuit
  • Territorial - Able to detect whether male or female bird are in their territory
  • Male - identify competition
  • Female - possible mate
• Bird song influenced by social learning

  1. Need exposure to conspecific songs during development to express appropriate behaviour

  2. Learning facilitated by exposure to social environment

  3. Development of activity in brain regions mirrors song development
• Proximate causes evolve - nervous system structures selected - specialised sensory receptors - central nervous system responsiveness to specific inputs - motor patterns produced - hormone receptors on neurons
• Define domestication 

  • A process driven by proximity with / management by humans 
  • Involves genetic changes over generations (ultimate) 
  • Involves developmental events in each generation (proximate) 
  • Most animals domesticated are large mammals - 10% of world  large mammals have been successfully domesticated 
  • Multiple domestication of wolves in different locations lead to different dog species 
  • Big five horses, sheep, goats, cattle, pigs 
• Accidental domestication in conservation breeding programmes

  • Animals born in captivity less alert/responsive to environment
  • Domestication process begun
• Causes of domestication in captivity

  1. Natural selection (advantage to less stressed in captivity)

  2. Relaxation of nervous system (no problem being laid back in captivity)
• Captive bred animals

  • Friendlier to humans
  • Less aggressive
  • More social
• Captive bred animals

  Less suitable for release (selected for captive suitable behaviour, less useful for supplementing wild populations in conservation)
• Captive bred animals

  Better welfare (better suited for life in captivity, less stress)