Full Idea
Each of the arctic animals is by its nature different from a penguin, so this general state of affairs seems truthmaker enough for this negative existential. Similarly, the totality of all birds eliminates the phoenix.
Clarification
There are no penguins in the Arctic! The phoenix does not exist!
Gist of Idea
The nature of arctic animals is truthmaker for the absence of penguins there
Source
David M. Armstrong (Truth and Truthmakers [2004], 06.2)
Book Reference
Armstrong,D.M.: 'Truth and Truthmakers' [CUP 2004], p.76
A Reaction
Why is it 'animals' in one case, and 'birds' in the other? What if there was no life in arctic? Would the snow then do the job? This doesn't seem to work.