I feel that one species, mankind, doesn't have the right to exterminate

A species consists of a group of populations which replace each other geographically or ecologically and of which the neighboring ones integrate or hybridise wherever they are in contact or which are potentially capable of doing so (with one or more of the populations) in those cases where contact is prevented by geographical or ecological barriers.

Evolution ... is opportunistic, hence unpredictable.

On Earth, among millions of lineages or organisms and perhaps 50 billion speciation events, only one led to high intelligence ; this makes me believe its utter improbablity.

In neither his definition nor the examples illustrating what memes are does Dawkins mention anything that would distinguish memes from concepts.

Evolution thus is merely contingent on certain processes articulated by Darwin: variation and selection.

Paleontologists had long been aware of a seeming contradiction between Darwin's postulate of gradualism, confirmed by the work of population genetics, and the actual findings of paleontology. Following phyletic lines through time seemed to reveal only minimal gradual changes but no clear evidence for any change of a species into a different genus or for the gradual origin of an evolutionary novelty. Anything truly novel always seemed to appear quite abruptly in the fossil record.