Diet and habitat of unique individuals of Dinohippus mexicanus and Neohipparion eurystyle (Equidae) from the late Hemphillian (Hh3) of Guanajuato and Jalisco, central Mexico: stable isotope studies

  • Víctor Adrián Pérez-Crespo Instituto de Geología, Universidad Nacional Autónoma de México, Circuito de la Investigación Científica S/N, Ciudad Universitaria, Del. Coyoacán, 04510, Ciudad de México, México.
  • Oscar Carranza-Castañeda Centro de Geociencias, Universidad Nacional Autónoma de México, Campus Juriquilla, Querétaro, 76230, México.
  • Joaquín Arroyo-Cabrales Laboratorio de Arqueozoología “M. en C. Ticul Álvarez Solórzano”, Subdirección de Laboratorios y Apoyo Académico, INAH. Moneda 16 Col. Centro, 06060, Ciudad de México, México.
  • Pedro Morales-Puente Instituto de Geología, Universidad Nacional Autónoma de México, Circuito de la Investigación Científica S/N, Ciudad Universitaria, Del. Coyoacán, 04510, Ciudad de México, México. Laboratorio Nacional de Geoquímica y Mineralogía-LANGEM, México.
  • Edith Cienfuegos-Alvarado Instituto de Geología, Universidad Nacional Autónoma de México, Circuito de la Investigación Científica S/N, Ciudad Universitaria, Del. Coyoacán, 04510, Ciudad de México, México. Laboratorio Nacional de Geoquímica y Mineralogía-LANGEM, México.
  • Francisco J. Otero Instituto de Geología, Universidad Nacional Autónoma de México, Circuito de la Investigación Científica S/N, Ciudad Universitaria, Del. Coyoacán, 04510, Ciudad de México, México. Laboratorio Nacional de Geoquímica y Mineralogía-LANGEM, México.
Keywords: Dinohippus mexicanus, Neohipparion eurystyle, stable isotopes, late Hemphillian, México

Abstract

Stable carbon and oxygen isotopes were determined in molar enamel from fossil Pliocene equids from Rancho El Ocote in the San Miguel Allende basin, Guanajuato, and from Santa María, Tecolotlán basin, Jalisco. At each locality, the source was one molar from an individual Dinohippus mexicanus and one molar from an individual Neohipparion eurystyle. Results indicated that the N. eurystyle individuals from both localities had been C3/C4 mixed feeders, and had lived in open-zone vegetation (δ13C: -3.1‰ to -1.3‰; δ18O: -4.9‰ to -6.4‰). On the other hand, the D. mexicanus from Rancho El Ocote had fed upon C4 plants and lived in open zones (δ13C: -1.3‰; δ18O: -4.9‰), whereas the D. mexicanus from Santa María was a C3/C4 mixed feeder with considerable consumption of C3 plants (δ13C: -7.7‰; δ18O: -6.4‰). These results could be contrast to suggestions from previous isotopic work that D. mexicanus in Mexico predominantly fed on C4 plants and further samples analyses are warranted. This study contributes to the understanding of the Pliocene equid taxa from central Mexico and emphasizes the presence of different diets, ranging from exclusive C4 to mixed C3/C4 plants.

Published
2017-04-01
Section
Articles