Converting statements with term 'only' and 'any' to predicate logic

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How to convert following statement into predicate logic?

1)"Only dogs are mammals"
2)"Any dog is a mammal"

Is there a difference between "Any dog is a mammal" and "All dogs are mammals" fro the view point of first order logic?

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The first is claiming that of all possible things or creatures, only dogs are mammals (I.e., anything other than a dog is not a mammal. I.e. all mammals are dogs.)


The second is indeed equivalent to "All dogs are mammals": i.e. "Considering all creatures, if any of them is a dog, then it is a mammal."

The second (unlike the first) does NOT rule out the fact that there may be non-dog creatures that are also mammals.