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ivory – n. a hard white substance that forms the tusks of elephants and other animals
well-preserved – adj. kept in good condition over a long period of time
evolutionary – adj. related to the theory that the differences between modern plants and animals are because of changes that happened by a natural process occurring over very long time
controversy – n. argument that involves many people who strongly disagree about something : strong disagreement about something among a large group of people
clone – v. to make an exact copy of a person, plant or animal
extinct – adj. no longer existing or living
hooves – n. plural, the hard coverings on the foot of an animal
nostril – n. one of two openings of the nose
sample – n. a small amount of something that gives you information about the thing it was taken from
specimen – n. a small amount or piece of something that can be tested or examined
