Video Experimental Relacionado
Updated: Nov 9, 2025
07:24
In Situ Hybridization Techniques for Paraffin-Embedded Adult Coral Samples
Published on: August 31, 2018
7.3K
Fossorialidad y desarrollo evolutivo en dos mamíferos del Cretácico
Fangyuan Mao1,2,3, Chi Zhang4,5, Cunyu Liu6
1Key Laboratory of Evolutionary Systematics of Vertebrates, Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences (CAS), Beijing, China. maofangyuan@ivpp.ac.cn.
Nature
|April 8, 2021
Resumen
Los fósiles recién descubiertos del Cretácico Temprano revelan una evolución convergente en los mamíferos. Estas especies antiguas, adaptadas para excavar, muestran signos tempranos de plasticidad en su esqueleto.
Área de la Ciencia:
- Paleontología
- Evolución de los vertebrados
- Biología del desarrollo
Sus antecedentes:
- Mammaliamorpha incluye a los antepasados y descendientes de Tritylodontidae y Mammalia.
- Los tritilodontidos fueron cinodontes herbívoros desde el Triásico Tardío hasta el Cretácico Temprano.
- Los Eutriconodontans se consideran un grupo de mamíferos extintos con diferentes clasificaciones.
Objetivo del estudio:
- Para reportar el descubrimiento de un nuevo tritylodontid y eutriconodontan de la Biota Jehol del Cretácico Temprano.
- Investigar las adaptaciones convergentes para la vida fossorial (excavadora) en estas especies distantes.
- Analizar los cambios evolutivos en el esqueleto axial y sus fundamentos de desarrollo en los mamíferos del tallo.
Principales métodos:
- Descubrimiento y análisis de fósiles dentro de la Jehol Biota.
- Morfología comparativa para identificar características convergentes y adaptaciones esqueléticas.
- Examen del recuento y las características vertebrales para inferir patrones de desarrollo.
Principales resultados:
- Descubrimiento de los primeros tritylodontids en el Jehol Biota, junto con los eutriconodontans comunes.
- Ambas especies exhiben adaptaciones convergentes para la vida fossorial, identificadas como "excavadoras de rasguños".
- Se observó un mayor número de vértebras presacrales con cambios merísticos y homeóticos, lo que indica cambios evolutivos.
Conclusiones:
- Estos fósiles proporcionan información sobre el desarrollo evolutivo del esqueleto axial de los mamíferos.
- Los hallazgos sugieren que la plasticidad del desarrollo en la somitogénesis y la expresión del gen HOX estaba presente en los mamíferos madreamorfos.
- La interacción de los mecanismos de desarrollo y la selección natural probablemente impulsó una evolución diversa del plan corporal en los clados de mamíferos.
Videos de Conceptos Relacionados
02:56The Fossil Record
26.4K
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...
26.4K
02:35What is Evolutionary History?
41.2K
Scientists record evolutionary history by analyzing fossil, morphological, and genetic data. The fossil record documents the history of life on Earth and provides evidence for evolution. However, both fossil and living organisms offer evidence that outlines Earth’s evolutionary history.
41.2K
01:54Convergent Evolution
30.2K
Evolution shapes the features of organisms over time, ensuring that they are suited for the environments in which they live. Sometimes, selection pressure leads to the rise of similar but unrelated adaptations in organisms with no recent common ancestors, a process known as convergent evolution.
30.2K
01:23Phylogeny
55.7K
Phylogeny is concerned with the evolutionary diversification of organisms or groups of organisms. A group of organisms with a name is called a taxon (singular). Taxa (plural) can span different levels of the evolutionary hierarchy. For instance, the group containing all birds is a taxon (comprising the class Aves), and the group of all species of daisies (the genus Bellis) is a taxon. Phylogenies can likewise include just one genus (i.e., depict species relationships) or span an entire kingdom.
55.7K
01:22Sutures of the Skull
9.0K
The human skull is composed of several bones that come together to protect the brain and support the structures of the face. The junctions where these bones meet are called sutures.
Sutures are immobile joints between adjacent bones of the skull. The narrow gap between the bones is filled with dense, fibrous connective tissue that unites the bones. The long sutures located between the skull bones are not straight but instead follow irregular, tightly twisting paths. These twisting lines tightly...
Sutures are immobile joints between adjacent bones of the skull. The narrow gap between the bones is filled with dense, fibrous connective tissue that unites the bones. The long sutures located between the skull bones are not straight but instead follow irregular, tightly twisting paths. These twisting lines tightly...
9.0K
02:22The Colonization of Land
36.1K
Changes in the environment of the early Earth drove the evolution of organisms. As prokaryotic organisms in the oceans began to photosynthesize, they produced oxygen. Eventually, oxygen saturated the oceans and entered the air, resulting in an increase in atmospheric oxygen concentration, known as the oxygen revolution approximately 2.3 billion years ago. Therefore, organisms that could use oxygen for cellular respiration had an advantage. More than 1.5 years ago, eukaryotic cells and...
36.1K