Myelin Advantages

(and a few disadvantages)

Myelin affects the nervous system, and hence the physiological and behavioral capabilities of an organism, in many ways. The primary impact is two-fold: on conduction speed and on the metabolic costs of nerve impulses. Beyond these, however, the list grows as more studies are made on organisms possessing it. Suggestions for the advantages include: These advantages conferred by myelin provide clear sources of selective pressure for its evolutionary invention. Myelin has a few disadvantages as well, that may deter its evolution or indeed promote the loss of myelin in the evolution of some organisms (see Myelin Evolution pages):
References:

Lenz, P.H. (2012) 
	The biogeography and ecology of myelin in marine copepods. 
	J. Plankton Res. 34: 575-589.
Wilson, C. and D.K. Hartline (2011) 
	The novel organization and development of copepod myelin. I. Ontogeny
	J. Comp. Neurol. 519: 32593280
Zalc, B. (2006) 
	The acquisition of myelin: a success story.  
	In Chadwick, D.J. and Goode, J., eds Purinergic Signalling in Neuron-Glia
	Interactions, No. 276 Wiley, Chichester. pp 15-25.
Zalc, B. and D.R. Colman  (2000) 
	Origins of vertebrate success 
	Science 288(5464) 271-272
Zalc, B., D. Goujet and D.R. Colman  (2008)  
	The origin of the myelination program in vertebrates.  
	Curr. Biol. 18(12): R511-R512


This material has been assembled and presented as a public service by Dan Hartline, Bekesy Laboratory of Neurobiology, Pacific Biosciences Research Center, University of Hawaii at Manoa (danh at hawaii.edu). Opinions expressed here are those of the author and do not represent the positon or policies of the University or any funding agency.