Patrick Cardozo
Dr Jeffrey Martz
Geo 1306
3/24/2017
Second research paper analysis;
Evolutionary trends in Triceratops from the Hell Creek Formation, Montana
The authors were interested in knowing the actual evolutionary trends in the triceratops from the Hell Creek Formation, Montana; Some previous Palaeontologists have recognised two Triceratops species, Triceratops horridus and Triceratops prorsus, due to the fact that the length and shape of the horns and the size and structure of the skull. However, scientists have been wary of the evolutionary relationship between the two Triceratops species. It was said that the two species could have been descendants of an extinct dinosaur, evolving as their ancestor's evolutionary tree which was split into two branches, in a process known as cladogenesis. But they argued If this were the case, both species would have lived at the same time, at perhaps different locations, where they would have developed some adaptations suitable for their distinct environments. But a different likelihood is that one species evolved …show more content…
When the team studied Triceratops skulls' morphology and position in the Hell Creek Formation, they found that skulls showing only features of T. horridus were present only in the lower section(L3) of the Hell Creek Formation, while skulls exhibiting only T. prorsus features were present only in the upper(U3) section of the Hell Creek Formation. The skulls found in the middle(M3) is said to have similar features of both species. This location shows that the two species most likely lived in the same place at different times. Therefore, T. horridus and T. prorsus probably did not evolve via the process of cladogenesis rather anagenesis, and that it was not possible for them to denote two sexes of a single species. The fossil record shows that T. horridus probably evolved into T. prorsus over one to two million
Dr Jeffrey Martz
Geo 1306
3/24/2017
Second research paper analysis;
Evolutionary trends in Triceratops from the Hell Creek Formation, Montana
The authors were interested in knowing the actual evolutionary trends in the triceratops from the Hell Creek Formation, Montana; Some previous Palaeontologists have recognised two Triceratops species, Triceratops horridus and Triceratops prorsus, due to the fact that the length and shape of the horns and the size and structure of the skull. However, scientists have been wary of the evolutionary relationship between the two Triceratops species. It was said that the two species could have been descendants of an extinct dinosaur, evolving as their ancestor's evolutionary tree which was split into two branches, in a process known as cladogenesis. But they argued If this were the case, both species would have lived at the same time, at perhaps different locations, where they would have developed some adaptations suitable for their distinct environments. But a different likelihood is that one species evolved …show more content…
When the team studied Triceratops skulls' morphology and position in the Hell Creek Formation, they found that skulls showing only features of T. horridus were present only in the lower section(L3) of the Hell Creek Formation, while skulls exhibiting only T. prorsus features were present only in the upper(U3) section of the Hell Creek Formation. The skulls found in the middle(M3) is said to have similar features of both species. This location shows that the two species most likely lived in the same place at different times. Therefore, T. horridus and T. prorsus probably did not evolve via the process of cladogenesis rather anagenesis, and that it was not possible for them to denote two sexes of a single species. The fossil record shows that T. horridus probably evolved into T. prorsus over one to two million