[2] Francisco Javier Muñiz was born in San Isidro, Buenos Aires Province, Argentina on 21 December 1795.

[4] His dissertation followed the article, "A Case of Extensive Scabby Ulcerations, Cured by Vaccination" that he wrote and was published in the London Medical and Surgical Journal in 1833.

[8] Rosas, in an attempt to build alliances overseas, sent collected fossils to Jean Henri Dupotet, Rear Admiral of the French Navy.

[7] Apuntes Toggraficos, published in 1847 by Muñiz, contained his topographical notes that discussed the study of fossils in the relative ages of sedimentary strata in areas south of the Buenos Aires Province by naturalists, including Charles Darwin.

Domingo Sarmiento, who researched Muñiz's papers, commented on his influence to Darwin's theory of the origin of species.

[9][10] This inquiry into the existence and later extinction of a variety of cattle raised on the ranches of Buenos Aires would be of little intellectual interest today, were it not thus linked with the celebrated theory of evolution, and the appears of Dr. Muñiz would be of lesser interest, too, except for the observations cited by Darwin in the Journal of Researches (commonly known as The Voyage of the Beagle).

[3] After having treated people with yellow fever during the great Buenos Aires epidemic, Muñiz succumbed to the illness and died on 8 April 1871.

In the natural sciences he followed in Darwin's footsteps, continuing his work and collecting the materials that Burmeister, with his greater technical skill, would later classify.