Simplify the following text for a Grade 13 native English-speaking person.
Original: Extinct in the Wild ( EW ) is a conservation status given to a species , a group of plants or animals , when the only known living members are being kept in captivity ( kept in a zoo , or planted in pots ) , or they are no longer living in their normal habitat .
Simplified: Extinct in the Wild ( EW ) is a conservation status assigned to species or lower taxa , the only known living members of which are being kept in captivity or as a naturalized population outside its historic range .