If you intend to construct a commencing series, at least
use a coordinating conjunction in your last member; or,
the last member of the series should lead to a climax.
Unfortunately, the fact that humans do 'it' (who's ante-
cedent is 'all mammals flirt') leaves the reader expect-
ing more. Therefore, your sentence has a comical affect
that makes one wonder if the outcome was intended. A more
definite sentence would follow the law of parallelism.