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		Procedure *Gamete collection from adult sea urchins *Fertilization of gametes *Calcium-Free from Fertilization *Using a sterile pipette, transfer fertilized eggs to a shallow finger bowl. *Add calcium-free seawater, allow eggs to settle, than remove excess liquid and replace with calcium-free seawater. *Allow eggs to developed and capture digital images several times during a 24-hour period. *Compare to control embryos which developed in ASW *Calcium-Free from Vegetal Plate stage *Using sterile pipette, transfer fertilized eggs to a shallow finger bowl. *Fill with ASW and allow development for 7 to 10 hours. Capture digital image in order to document transfer to calcium-free seawater. *Remove excess ASW and replace with calcium-free seawater. Repeat several times in order to remove as much calcium as possible. *Allow eggs to continue development for another 14-17 hours. Capture digital images of embryos. *Compare with control embryos which developed in ASW *Control Embryos *Using sterile pipette, transfer fertilized eggs to a shallow finger bowl. Fill with ASW. *Allow growth for the same time as the experimental embryos. Capture images a same time as experimental embryo for comparison.