180498
It was concluded that in some species of cooperative birds egg-tossing is a strategy of clutch coordination : eggs are tossed until all birds in the common nest are ready to proceed with brooding , so that early egg-layers do not dominate the reproduction .
 None
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: location, person, organization 
Text: {0} 
Answer:
 None