For one, the researcher discovered that there was a structure called Meckel's cartilage that was present between the incus, or anvil bone, of the middle ear and the lower jawbone of Yanoconodon. Why is this so important? Well, coincidentally, in the developing human embryo the lower mandible transforms and produces the bones of the middle ear. As the embryo further evolves, the identical Meckel's cartilage is produced as the bones migrate from the jaw to the middle ear. Afterwards the cartilage is dissolved into fibrous membranes and becomes part of the jawbone again and dissapears. This is the first time the presence of Meckel's cartilage was found in a fully developed mammal. This also adds some credence to an old saying "ontogeny capitulates phylogeny," or in English the stages in the development of the embryo mirrors the evolutionary stages in the development of the species. While intriguing and also not altogether true, it certainly becomes another one of the fascinating aspects of this find. It is also a rare and previously undocumented discovery of finding the existence of Meckel's cartilage in the fossilized remains of any prior specimens.

Their discovery that this species is also remodeling it lower back to conform to the more modern delineation between upper and lower vertebrae present in modern mammals added to the growing "missing link" reputation of this specimen. They also theorize that on a genetic level this is an important discovery as well. A cluster of genetic material called the Homeobox gene governs the creation...

It had been theorized that this set evolved from a set of genes called the Hox gene cluster, which evolved during the Paleozoic era.
The authors assert that this transitional spinal appearance clearly shows the genetic transition from Hox to Homeobox as well. An assertion not supported by many of their peers, but certainly leads to more intriguing research on the subject. The genetic source of evolution has always been thought provoking to both geneticist and evolutionary researchers.

This discovery may show that the development of these key mammalian traits in modern humans may have begun to develop long before anyone had previously thought they had, and certainly long before the development of human beings. While the possibility also exists that this may be an aberration and that this development arose and disappeared and arose again in modern mammals is also a distinct possibility, and many of their fellow researches seemed to think the latter case is more likely. More transitional fossils like this one need to be found in order to corroborate this singular find. However, the rarity of the find coupled with the unusual evolutionary connections, is certainly raising many questions in the scientific community. And questions are the beginning of true knowledge.

Works Cited

Luo, Z., Chen, P., Li, G., Chen, G. & Chen, M. "A New Eutriconodont Mammal and Evolutionary Development in Early Mammals." Nature, (2007) Vol 446; 288-293