Search results
Results From The WOW.Com Content Network
Exactly why the trilobites became extinct is not clear; with repeated extinction events (often followed by apparent recovery) throughout the trilobite fossil record, a combination of causes is likely. After the extinction event at the end of the Devonian period, what trilobite diversity remained was bottlenecked into the order Proetida.
Angelina Salter, 1859, [1] is a genus of ptychopariid trilobite belonging to the Family Olenidae, Suborder olenina. It lived during the Tremadocian Stage, lowermost of the two standard worldwide divisions forming the Lower Ordovician Series and lowest of the seven stages within the Ordovician System. It encompasses all rocks formed during ...
Cedaria is an extinct genus of trilobites from the late Cambrian.. It is a small, rather flat trilobite with an oval outline, a headshield and tailshield of approximately the same size, 7 articulating segments in the middle part of the body and spines at the back edges of the headshield that reach half the length of the body.
Wanneria is an extinct genus from a well-known class of fossil marine arthropods, the trilobites. It lived during the later part of the Botomian stage, [3] which lasted from approximately 524 to 518.5 million years ago. This faunal stage was part of the Cambrian Period. [3] W. walcottana and W. cranbrookense are the only known species in this ...
The timeline of human evolution outlines the major events in the evolutionary lineage of the modern human species, Homo sapiens, throughout the history of life, beginning some 4 billion years ago down to recent evolution within H. sapiens during and since the Last Glacial Period.
Trinia Poletaeva, 1956, [2] is an extinct genus from a well-known class of fossil marine arthropods, the trilobites. It lived during the Cambrian Period, [1] which lasted from approximately 542 to 488 million years ago.
Weymouthia is an extinct genus of eodiscinid agnostid trilobites which lived at the end of the Lower Cambrian. Its fossils are found in Lower Cambrian marine strata from what are now the eastern United States, England, Siberia and China.
Balnibarbi is an extinct genus of trilobites in the family Olenidae. They are known from fossils excavated in Norway. They lived during the early part of the Arenig stage of the Ordovician Period, a faunal stage that occurred about 479 to 472 million years ago. [2] The genus is ancestral to, and co-existed sympatrically with, the better-known ...