Being the inventor of sex would seem to be a sufficient distinction for a creature just barely large enough to be seen by the naked eye.
[Comment about Volvox, a freshwater green algae, which appears indetermimately plantlike and animal-like during its reproductive cycle.]

If only the fit survive and if the fitter they are the longer they survive, then Volvox must have demonstrated its superb fitness more conclusively than any higher animal ever has.

We must be part not only of the human community, but of the whole community; we must acknowledge some sort of oneness not only with our neighbors, our countrymen and our civilization but also some respect for the natural as well as for the man-made community. Ours is not only 'one world' in the sense usually implied by that term. It is also 'one earth'. Without some acknowledgement of that fact, men can no more live successfully than they can if they refuse to admit the political and economic interdependency of the various sections of the civilized world. It is not a sentimental but a grimly literal fact that unless we share this terrestrial globe with creatures other than ourselves, we shall not be able to live on it for long.