Simplify the following text for a Grade 10 native English-speaking person.
Original: Species which have not been evaluated ( NE ) , or do not have sufficient data ( Data Deficient ) also are not considered `` threatened '' by the IUCN .
Simplified: When the species has not been studied , Not Evaluated , or there is not enough information , Data Deficient , the IUCN does not put them on the threatened species list .