Bibette & Lulu, U would have solved nearly the whole puzzle, and was a big clue! rarely is it doubled, but it is in Equus!

But mrsspunkysmom solved it, it was:


As it turns out, Horse initiated the deal between Horse and Human.

In 1867 archeologists found on the American continent the remains of
the Dawn Horse, which dated back sixty million years, to the Eocene period.
The species called Eohippus evolved about a million years ago into Equus Callabus*,
ancient ancestor to the modern horse. Migrating from the American continent
using land bridges to Europe and Asia, Equus and its many species made
their way into every corner of the world and adapted to every climate on the planet.
*however Callabus is misspelled, a mistake I made when transcribing the quote, sorry very one, it should be "Caballus"

Anyway, she has asked that I pass it along to the highest pointgetter, which is happylabs by a landslide!