What mammal was the first to be cloned?

Let's just admit it: By now we thought we'd all have cloning machines at home and would be able to just clone ourselves anytime there was a chore we didn't really want to do. Yes, this would inevitably lead to chaos, but it's still better than doing the actual chore.

While we're not quite there yet, cloning is indeed a thing. Turns out there are all kinds of ethical and scientific challenges, but hey, yay science!

In fact, it's now not totally out of the question to clone your dog, even if it is questionable in other senses of the word. To get to this point, someone had to be the first to clone a mammal — but which mammal did they use to do so?

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