In 2016, it was confirmed that they belonged to an evolutionary branch that split from hedgehogs and shrews before the K-T extinction.
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These creatures have several unusual traits: their teats are located on their bottoms, and their saliva are venomous.They live in bushy areas in forests,hiding in burrows or hollow logs.
Both species were thought to be extinct, until a Cuban Solenodon was found in 2003. The Hispaniolan solenodon was assumed extinct because of its elusive behavior instead of low numbers. Both species are currently endangered.