The CORE FOUR Biomedical Model Systems of Biology

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Valerie Bridges
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November 21, 2011 Why? The core four all have accessible genetics and genomics.

Neuroethology the study of non-traditional model systems: what we lose by focusing on the

Begin with behavior in the wild. Not Lab Rats.

an organism best suited for its study. Look for extreme adaptations; study animal specialists.

giant axon: Hodgkin, Huxley, Cole Ionic basis of electrical excitability: the H-H Equations.

1 Is Neuroethology Dead? The CORE FOUR Biomedical Model Systems of Biology Genetic Models Ron Hoy Neuroethology Class November 21, 2011 Why? The core four all have accessible genetics and genomics. The mission of NIH is Translation of funded research to address human disorders and illnesses by drugs & chemical interventions. The animal systems of neuroethology don t fit the NIH program. Neuroethology the study of non-traditional model systems: what we lose by focusing on the final four. Neuroethology s 3 Axioms Agassiz s Rule: Study nature, not books. Begin with behavior in the wild. Not Lab Rats.convenient domesticated lab animals Krogh s Principle: For every problem in biology there is an organism best suited for its study. Look for extreme adaptations; study animal specialists. Extremophilic & Opportunistic Modern Neuroscience s First Model: the squid, Loligo peali The giant axon: Hodgkin, Huxley, Cole Ionic basis of electrical excitability: the H-H Equations. The giant synapse both pre-and post-synaptic partners accessible. Synaptic activity & Calcium-triggered secretion. The molecular biology of synaptic transmission. Dobzhansky s Maxim: Nothing in biology makes sense except in light of evolution. Biology s theory of everything why the comparative approach in neuroscience works. 1

2 Animal brainiacs Auditory Processing Aplysia californica Honeybee, Apis mellifora Directionality by computation. Neural maps of auditory space. Seeing by hearing auditory maps in mammalian cortex. Zebra finch How cochlear & vestibular hair cells work mechanoelectrical transduction at Molecular level. Central Pattern Generators Motor Systems Forward Models: Corollary Discharge mormyrids, crickets, pleurobranchia Motor Systems CPG City Command Hierarchies leeches (Broadfuehrer), pleurobranchia (Davis), crustacea (Jeff Wine) Neuromodulation, Plasticity, Homeostasis songsters Auditory Processing Visual Systems Directionality by computation. Neural maps of auditory space. Seeing by hearing auditory maps in mammalian cortex. How cochlear & vestibular hair cells work mechanoelectrical transduction at Molecular level. 2

Chemical Systems Ormia ochracea: auditory

Ormia ochracea The parasite, Ormia ochracea,

sensitive hearing enables it to locate and

and an auditory specialist Cade, Science, 1987.

If I were starting out now sound inlet ports

neuroethology acolyte following the 3 tenets of

3 Chemical Systems Ormia ochracea: auditory specialist par excellence Acoustic parasitoid, Ormia ochracea The parasite, Ormia ochracea, finds its host by hearing & homing in on its mating call. Ormia unusual among flies - it has ears Ormia s sensitive hearing enables it to locate and parasitize crickets Ormia is nocturnally active and an auditory specialist Cade, Science, Application: Directional Hearing Aid Microphone If I were starting out now sound inlet ports microphone array a) b) If I were your age and a neuroethology acolyte following the 3 tenets of neuroethology-- the gospel according to Saint Agassiz, Krough, and Dobzhansky 3.5 mm 4.5 mm 3

other senses Does accommodating high acuity vision

An enabling adaptation A Classic Visual Specialist:

Convergent Evolution of Eyes Focusing lens/cornea on

telephoto functionality Very high resolution eye The

4 Is Vision Special? It is massively parallel sensory channel compared to other senses Does accommodating high acuity vision enable the evolution of high intelligence? An enabling adaptation A Classic Visual Specialist: Jumping spiders have a pair of large frontal eyes Convergent Evolution of Eyes Focusing lens/cornea on surface True retina Deeper, second lens permits telephoto functionality Very high resolution eye The eye-tube is movable to produce systematic scanning movements. Drag lines are the original bungee cords 4

Proportion copulated 12/1/2011 Jumping spiders are

Hebets, Maddison, or Hedin Synchronized,

s acoustic signals appear to emphasize and

Both tonic and phasic components provide substrates

The combinatorial possibilities enable the sender

receiver to assess it is there a binding problem?

5 Proportion copulated 12/1/2011 Jumping spiders are renowned for their ostentatiously visual courtship displays Memory? The peacocks of the spider world Photos by Elias, Hebets, Maddison, or Hedin Synchronized, orchestrated multimodal signals The jumping spider s acoustic signals appear to emphasize and punctuate visual signals, and viceversa. Both tonic and phasic components provide substrates for selective attention. The combinatorial possibilities enable the sender to grade the intensity of his signal and the receiver to assess it is there a binding problem? Dissociating sight from sound Muted with wax abdomen cannot vibrate. Waxed but not muted Measure of male courtship success = copulation. Results (Mating behavior) Results (latency to copulation) (Χ 2 = 7.817, **p<0.01) Latency: begin courtship to copulation 5

Proportion Cannibalized 12/1/2011 Results (pre-mating cannibalization)

Cognition is multimodal Its study in weird little bugs might have

of animal awareness the evolutionary emergence of consciousness CPGs

and acoustic signals and sexual selection.

6 Proportion Cannibalized 12/1/2011 Results (pre-mating cannibalization) Multimodality and its Implications. Cognition is multimodal Its study in weird little bugs might have something to say about the elements of perceptual awareness the nature of animal awareness the evolutionary emergence of consciousness CPGs drive the spider s courtship displays Multimodal coordination of visual and acoustic signals and sexual selection. The CPGs are related to locomotory acts But that s not all intentionality and preycapture in stalking behavior. Example 2: Octopus Behavior 6

7 Brain Slice Preparation 7

Sensory Worlds: The neural basis of animal behaviour. Dr. Katie Lucas Learning in Retirement Winter 2018

Sensory Worlds: The neural basis of animal behaviour Dr. Katie Lucas Learning in Retirement Winter 2018 The Field of Neuroethology The neural basis of natural adaptive behaviour Environmental Signal Stimulus