El 21 de enero es el 21.ᵉʳ (vigésimo primer o vigesimoprimer) día del año en el calendario gregoriano. Quedan 344 días para finalizar el año y 345 en los años bisiestos.
LA RAE Y LA Falacia DEL Panhispanismo: Análisis Crítico DE LA Preeminencia DE España EN LA Vigesimotercera Edición DEL Diccionario DE LA Lengua Española
The natural history of Earth concerns the development of planet Earth from its formation to the present day. [1 ] [2 ] Nearly all branches of natural science have contributed to understanding of the main events of Earth's past…
The ancient Egyptians mummified an abundance of cats during the Late Period (664-332 BC). The overlapping morphology and sizes of developing wildcats and domestic cats confounds the identity of mummified cat species.
What explains the genetic relationship between Egyptian cat mummies and modern domestic cats?The study reveals that two of the three analyzed cat mummies contained mitotype sequences similar to modern domestic cats, specifically mitotypes C and G, indicating a genealogical link.How did morphological analysis contribute to identifying species in cat mummies?Morphometric analyses indicated a range of sizes and growth metrics among mummified cats, complicating definitive species identification due to overlapping characteristics.When did ancient Egyptians begin the practice of cat mummification?The first indication of cat mummification dates back to approximately 1350 B.C., associated with burial practices of beloved pets.
Las ciencias formales (por ejemplo, lógica, matemáticas y ciencia computacional teórica), que estudian sistemas formales regidos por axiomas y reglas, [5 ] [6 ] a veces también se describen como ciencias; sin embargo, a menudo se consideran…