Video Experimental Relacionado
Updated: Jul 12, 2026

11:14
Fatty Acid 13C Isotopologue Profiling Provides Insight into Trophic Carbon Transfer and Lipid Metabolism of Invertebrate Consumers
Published on: April 17, 2018
Las proporciones de isótopos estables de carbono como medida de la proteína marina frente a la terrestre en las
Resumen
Las proporciones de isótopos estables de carbono revelan diferencias claras entre la carne de animales marinos y terrestres. Estos valores isotópicos de carbono (delta) en el colágeno humano pueden reconstruir las dietas prehistóricas.
Área de la Ciencia:
- Paleoecología Paleoecología.
- La geoquímica de los isótopos es la geoquímica de los isótopos.
- Arqueología Arqueología.
Sus antecedentes:
- Los ecosistemas marinos y terrestres exhiben distintas firmas de isótopos estables de carbono.
- Estas diferencias isotópicas son rastreables a través de la red alimentaria hasta los consumidores máximos, incluidos los humanos.
- Comprender estas firmas es crucial para reconstruir entornos y dietas pasadas.
Objetivo del estudio:
- Para investigar las relaciones de isótopos estables de carbono en animales marinos y terrestres de la costa del Pacífico de Canadá.
- Para determinar si estas diferencias isotópicas se reflejan en los consumidores humanos.
- Para establecer la utilidad de los valores isotópicos de carbono (delta) en el colágeno humano para el análisis de las dietas prehistóricas.
Principales métodos:
- Análisis de las proporciones de isótopos estables de carbono (delta) en muestras de carne de animales.
- Comparación de los valores isotópicos entre la fauna marina y la terrestre.
- Medición de los valores isotópicos de carbono en el colágeno humano.
Principales resultados:
- Se observó una diferencia significativa de 7.9 +/- 0.4 por mil entre la carne de animales marinos y terrestres.
- Esta fraccionamiento isotópico refleja la diferencia conocida entre las reservas oceánicas y atmosféricas de carbono.
- Los valores isotópicos de carbono en el colágeno humano se correlacionan directamente con la proporción de fuentes de alimentos marinas frente a las terrestres consumidas.
Conclusiones:
- El análisis de isótopos estables de carbono proporciona un método confiable para diferenciar el consumo de alimentos marinos y terrestres en poblaciones pasadas.
- Las dietas humanas prehistóricas se pueden evaluar cuantitativamente mediante el análisis de los valores delta ((13) C en su colágeno.
- Esta investigación mejora nuestra comprensión de las estrategias de subsistencia y la utilización de los recursos en las comunidades costeras del pasado.
Videos de Conceptos Relacionados
The Fossil Record
The fossil record documents only a small fraction of all organisms that have ever inhabited Earth. Fossilization is a rare process, and most organisms never become fossils. Moreover, the fossil record only exhibits fossils that have been discovered. Nevertheless, sedimentary rock fossils of long-lived, abundant, hard-bodied organisms dominate the fossil record. These fossils offer valuable information, such as an organism's physical form, behavior, and age. Studying the fossil record helps...
Radioactive Decay and Radiometric Dating
Radioactivity is a spontaneous disintegration of an unstable nuclide and is a random process, as all the nuclei in the sample do not decay simultaneously. The number of disintegrations per unit time is called the activity (A), which is directly proportional to the number of nuclei in the sample. The decay constant (λ) is an average probability of decay per nucleus in unit time.
The Carbon Cycle
Carbon is the basis of all organic matter on Earth, and is recycled through the ecosystem in two primary processes: one in which carbon is exchanged among living organisms, and one in which carbon is cycled over long periods of time through fossilized organic remains, weathering of rocks, and volcanic activity. Human activities, including increased agricultural practices and the burning of fossil fuels, has greatly affected the balance of the natural carbon cycle.
Mass Spectrometry: Isotope Effect
Most elements exist in nature as a mixture of isotopes. The isotopes differ in weight due to their respective number of neutrons. The molecular weight of a molecule is different depending on the specific isotope of its elements involved. As a result, the mass spectrum of the molecule exhibits peaks from the same fragment at multiple positions. The positions of these mass signals depend on the mass differences between isotopes. Furthermore, the intensity of these signals is dependent on the...
Isotopes
Elements have a set number of protons that determines their atomic number (Z). For example, all atoms with eight protons are oxygen; however, the number of neutrons can vary for atoms of the same element. The sum of the number of protons and the number of neutrons is the mass number (A). Atoms with the same atomic number but different mass numbers are called isotopes. Elements can have multiple isotopes, for example, carbon-12, carbon-13, and carbon-14.An element's atomic mass, or weight, is a...
Carbon-13 (¹³C) NMR: Overview
Carbon-13 is a naturally occurring NMR-active isotope of carbon with a low natural abundance of 1.1%. In contrast, carbon-12 is the most abundant isotope of carbon with zero nuclear spin. Therefore, it is NMR inactive. The gyromagnetic ratio of carbon-13 is smaller than that of protons. As a result, carbon-13 resonance is about 6000 times weaker than proton resonance. For a given magnetic field strength, the resonance frequency of carbon-13 is about one-fourth of the resonance frequency for...

