Ovipary is the laying of eggs. Every bird and turtle and most amphibians and fish are oviporous, as are some snakes and some lizards. These species have everything a developing embryo needs in a self contained egg. The egg may have a leathery or ridig shell. I chicken egg is typical of this type of reproduction.



Vivipary is how you were born. Most mammals and even some reptiles are viviparous. This is very similar to oviporous reproduction EXCEPT there is now shell of any kind. The embryo develops in the mothers body AND there is a direct conection to the mother through wich the embryo is nurished. The embilical cord was your connection to mom. The platypus and the spiney echidna are OVIPAROUS MAMMALS.



Ovovivipary has characteristics of both. The eggs are held within the mothers body BUT THERE IS NO CONNECTION to mom. The eggs develop in the mother as they would in the ground. Once the young hatch they are "born" or stay in the mom a bit longer to develop more. They either feed off yolk sac or some other wierd souce. Some caceclians (type of amphibian) secrete a "food" from the walls of mom's uterus. The young scrape it off with rake-like teeth. Some sharks actaully eat their siblings! (Pretty freakin' cool huh?) Some lizards, snakes, sharks, fish and amphibians are ovoviviparous.



Hope that helps and is not more than you wanted.



Brian

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