Amphioxus Locomotion

Amphioxus Nervous System  is interesting, so I'm going to start there.   

The long list of links in "Cross references", above, to pages in 
Children of the Amphioxus  is intended to provide general background
to amphioxus locomotion. 

amphioxus locomotion - Google Search 
- 25,000 references   

    NOTE:  This article assumes that the amphioxus is predominately mobile. 
This disputes the view that the amphioxus remains buried in the sand for
most of the time. 

amphioxus locomotion - Mozilla Yahoo Search Results - 48,000 references  


amphioxus locomotion - PubMed  - 13 references       
New perspectives on the evolution of protochordate sensory and
locomotory systems, and the origin of brains and heads.   
Free PMC Article                  
    "Cephalochordates (i.e. amphioxus) are segmented and resemble vertebrates in having two distinct locomotory modes, slow for distance swimming and fast for escape, that depend on separate sets of motor neurons and muscle cells. The sense organs of both amphioxus and tunicate larvae serve essentially as navigational aids ..." 
    "Similarities between amphioxus and tunicate sense organs are then most easily explained if distance swimming evolved before and escape behaviour after the two lineages diverged, leaving tunicates to adopt more passive means of avoiding predation.

    Also:  Amphioxus Evolution  and  Amphioxus Fast-Slow Twitch 

Dorsal Compartment Locomotory Control System (PubMed)   
    See:  Dorsal Motor Neurons 

Ventral neurons in the anterior nerve cord ... I (PubMed)   
  Please see:
  Ventral Motor Neurons

Ventral neurons in the anterior nerve cord of amphioxus larvae. II. Further data on the pacemaker circuit. (Goog)   
    Please see:   Ventral Motor Neurons

Tuning and playing a motor rhythm: how metabotropic glutamate receptors orchestrate generation of motor patterns in the mammalian central nervous system (Goog) 

Full length HTML available online for free. 
    Please see:
  Amphioxus Glutamate 

The cholinergic gene locus in amphioxus: molecular characterization and developmental expression patterns.   
    "Amphioxus has three types of motoneurons, ventral compartment (VC) motoneurons, which innervate the fast fibers of the myotome, dorsal compartment (DC) ones, which innervate the slow fibers, and visceral motoneurons, which innervate all other body muscles "   
My comment
    Searching Google for "fast twitch muscles" yielded 1,120,000 claimed hits.   Are human fast and slow twitch muscles innervated by different nerves? 
Muscle Innervation  and  Amphioxus Fast-Slow Twitch  .         

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