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Gobiconodontidae is a family of extinct mammals that ranged from the mid-Jurassic to the early Late Cretaceous, though most common during the Early Cretaceous. [6] The Gobiconodontids form a diverse lineage of carnivorous non-therian mammals, and include some of the best preserved Mesozoic mammal specimens.
Extinct vertebrates since 1500 (5 C) A. Extinct amphibians (2 C, 22 P) B. Extinct birds (10 C, 4 P) F. Extinct fish (3 C, 3 P) M. Extinct mammals (8 C, 14 P) R ...
Everett Claire Olson (November 6, 1910 – November 27, 1993) was an American zoologist, paleontologist, and geologist noted for his seminal research of origin and evolution of vertebrate animals. [1] [2] [3] Through his research studying terrestrial vertebrate fossils he identified intervals of extinction in the Permian [4] and Triassic. [5]
Agnatha (/ ˈ æ ɡ n ə θ ə, æ ɡ ˈ n eɪ θ ə /; [3] from Ancient Greek ἀ-(a-) 'without' and γνάθος (gnáthos) 'jaws') is a paraphyletic infraphylum [4] of non-gnathostome vertebrates, or jawless fish, in the phylum Chordata, subphylum Vertebrata, consisting of both living (cyclostomes) and extinct (conodonts, anaspids, and ostracoderms, among others).
Evolution and extinction of placoderms. The diagram is based on Michael Benton, 2005. [17] Dunkleosteus, among the first of the vertebrate apex predators, was a giant armoured placoderm predator. Amazichthys, a pelagic arthrodire from the Middle Famennian of the Late Devonian. Fin spine of Eczematolepis, from the Middle Devonian of Wisconsin
After the appearance of jawed fish (placoderms, acanthodians, sharks, etc.) about 420 million years ago, most ostracoderm species underwent a decline, and the last ostracoderms became extinct at the end of the Devonian period. More recent research indicates that fish with jaws had far less to do with the extinction of the ostracoderms than ...
The class Osteostraci (meaning "bony shells") is an extinct taxon of bony-armored jawless fish, termed "ostracoderms", that lived in what is now North America, Europe and Russia from the Middle Silurian to Late Devonian. Anatomically speaking, the osteostracans, especially the Devonian species, were among the most advanced of all known ...
Extinction of taxa is difficult to detect, as a long gap without a sighting is not definitive. Some mammals declared as extinct may very well reappear. [1] For example, a study found that 36% of purported mammalian extinction had been resolved, while the rest either had validity issues (insufficient evidence) or had been rediscovered. [3]