The harsh desert environment ensured that only the strongest and keenest horse survived, and it was responsible for many of the physical characteristics distinguishing the breed to this day.
(The harsh desert environment; ensured; that only the strongest and keenest horse survived, and it was responsible for many of the physical characteristics) (horse; survived; ) (it; was; responsible for many of the physical characteristics) (many of the physical characteristics; distinguishing; the breed; to this day)
The harsh desert environment horse it many of the physical characteristics
ensured survived was distinguishing
that only the strongest and keenest horse survived, and it was responsible for many of the physical characteristics
responsible for many of the physical characteristics
the breed to this day