Another post on the possibility of extant megafaunal horses in South America in the 1500s.
This continues my previous post on the subject.
I have found some references (more below) stating that Spanish explorers sighted natives riding horses in the region next to the Strait of Magellan in 1580. I decided to check the original sources and was surprised to find out that it was not so!:
Sarmiento de Gamboa 1580s
The account of the adventures and exploration of the Strait of Magellan can be found in Sarmiento de Gamboa's book . And, there is an interesting part covering the interrogation that Tomé Hernandez faced in Lima, Peru in 1620 (forty years after the events).
Tome had traveled under the command of Pedro Sarmiento de Gamboa to settle the Strait of Magellan in 1581. The expedition managed to set up two small villages but the ships with supplies never arrived and this doomed the colonies. The settlers were left to die of starvation and disease. The natives accosted them. And very few were alive two and a half years later when English privateer Thomas Cavendish sailed by and offered to take them to Chile.
All except one refused (they were Catholics, Cavendish an English protestant and enemy of Spain), Tomé.
Many years later, the Spaniards, worried about the intentions of the English regarding Patagonia and, also, wanting to know more about that mysterious area, interrogated him.
The image below highlights the interrogation regarding horses. I will translate it:
When Asked: Do the Indians rode horses and if there are any in that land? He Said: That whenever he saw them, they were on foot and that he saw no horses at all
However Charles Darwin, in his "Voyage of the Beagle" wrote  about the "Indians" by the Strait of Magellan:
"In the time of Sarmiento (1580), these Indians had bows and arrows, now long since disused; they then also possessed some horses.
This is a very curious fact, showing the extraordinarily rapid multiplication of horses in South America. The horse was first landed at Buenos Ayres in 1537, and the colony being then for a time deserted, the horse ran wild;* in 1580, only forty-three years afterwards, we hear of them at the Strait of Magellan! Mr. Low informs me, that a neighbouring tribe of foot-Indians is now changing into horse-Indians: the tribe at Gregory Bay giving them their worn-out horses, and sending in winter a few of their best skilled men to hunt for them. 
I went over the text of Gamboa's book and he never mentions horses, only (on page 95 see pdf link below ), "deer" and "anta" (that is, tapir... I have posted on tapir in Patagonia elsewhere.)
So, in all fairness, Darwin misinterpreted Sarmiento's text assuming there were horses here. Sarmiento never mentioned horses. Other Spanish authors of the time did, but not Sarmiento.
 xxvii Page Viage al Estrecho de Magallanes por el Capitan Pedro Sarmiento de Gambóa en ... By Pedro Sarmiento de Gamboa 1768
 Darwin, C. R. 1845. Journal of researches into the natural history and geology of the countries visited during the voyage of H.M.S. Beagle round the world, under the Command of Capt. Fitz Roy, R.N. 2d edition. London: John Murray. pp 232
Patagonian Monsters - Cryptozoology, Myths & legends in Patagonia Copyright 2009-2013 by Austin Whittall ©