Mesozoic [USEMAP] Conodonts – end Triassic extinction. Actinopterygii In Triassic Holostei domination. In Jurassic expansion of Teleostei which become the dominant Fish group. Other groups of actinopterygii retreat. In Cretaceous e.g. Paleoniscida become extinct. Actinopterygii Chondrostei – dominat late Paleozoic fish group Holostei- dominant in Triassic Teleostei- dominant since Jurrasic Sharks – In Triassic important hybodonts, button-like teeth, crushing of bivalve test. In Jurassic expansion. And modern families appear. In Cretaceous 12 of 16 recent families. Cretoxyrhina was one the largest sharks of its time, reaching lengths of up to 7 metres (23 ft)[4] and was a chief predator in its ecosystem, preying on a variety of marine animals, including marine reptiles like mosasaurs and plesiosaurs, and other large fish Tertiary – Carcharodon megalodon – 20m. Megalodon byl v kompetičním vztahu s kytovci lovícími jiné velryby, kteří možná přispěli k jeho vyhynutí. Vzhledem k tomu, že žil primárně v teplých vodách, za jeho vyhynutí mohl i nástup ledové doby či ochlazení oceánů. Crossopterygii, Dipnoi – Triassic last system in which higher representation Today – „living fossils“ [USEMAP] [USEMAP] [USEMAP] [USEMAP] [USEMAP] Amphibians – in Triassic still Paleozoic group Temnospondyli, retreat and end Triassic extinction, reduced survival till mid Jurassic. New modern groups appear in Triassic. First frogs (Anura)– Triadobatrachus massinoti Gradual entry of other modern groups in Jurassic and Cretaceous. Furtehr groups of modern amphibians –Caudata- salamanders (mloci), Gymnophiona (červoři) triado4 [USEMAP] červoři mloci žáby [USEMAP] Gymnophiona [USEMAP] Gymnophiona Reptile Subclasses: 1 – Anapsida O. Cotylosauria- stem reptiles O. Chelonia - turtles & tortoises •unchanged for about 175 million years •identified by bony dermal plates to which ribs & trunk vertebrae are fused 2 - Lepidosauria O. Rhynchocephalia (Sphenodonta) - only living representative is the Tuatara(hatérie) O. Squamata - lizards, geckos, & snakes 3 -Archosauria O. Thecodontia – stem archosaurs O. Pterosauria O. Saurischia- 2 major groups: sauropods & theropods O. Ornithischia O. Crocodilia 4 - Euryapsida - marine reptiles, includes the plesiosaurs & ichtyosaurs Dinosauria Anapsids, diapsids, euryapsids [USEMAP] Anapsida Euryapsids [USEMAP] 2 - Lepidosauria O. Rhynchocephalia (Sphenodonta) - only living representative is the Tuatara O. Squamata - lizards, geckos, & snakes 3 -Archosauria O. Thecodontia – stem archosaurs O. Pterosauria O. Saurischia- 2 major groups: sauropods & theropods O. Ornithischia O. Crocodilia 4 - Euryapsida - marine reptiles, includes the plesiosaurs & ichtyosaurs Lepidosaurs – radiation at the beginning of Triassic, Small lizard-like reptiles. Predecessors of thecodonts (Permian) and Squamata (Triassic) Thecodonts – wide expansion in early and middle Triassic. End Triassic extinction (dinosaurs?) Postosuchus was one of the largest carnivorous reptiles during the late Triassic Crocodiles – Triassic, thecodont predecessors. Originally land animals, secondary to water environment. Great expansion in Jurassic, mostly in seas. In Cretaceous gigantic forms as 15m Phobosuchus. [USEMAP] Cotylosaurs – end Triassic extinction Land Reptiles Chelonia – originally terrestrial animals, late Jurassic transition tomarine environment. Cretaceous – 4m Archelon m%20To%20the%20Beach [USEMAP] rephist [USEMAP] Snakes Snakes are thought to have evolved from either burrowing or aquatic lizards, perhaps during the Jurassic period, with the earliest known fossils dating to between 143 and 167 Ma ago.[10] The diversity of modern snakes appeared during the Paleocene epoch (c 66 to 56 Ma ago, after the Cretaceous–Paleogene extinction event). Squamata(šupinatí) - lizards, geckos, & snakes [USEMAP] [USEMAP] Lizards The earliest known fossil remains of a lizard date to the Late Triassic. Mosasaurs probably evolved from an extinct group of aquatic lizards known as aigialosaurs in the Early Cretaceous. During the last 20 million years of the Cretaceous period (Turonian–Maastrichtian ages), with the extinction of the ichthyosaurs and pliosaurs, mosasaurs became the dominant marine predators. They became extinct as a result of the K-Pg event at the end of the Cretaceous period, about 66 million years ago [USEMAP] [USEMAP] The early ancestors of mosasaurs probably fed in the ocean and returned to land much like the marine iguanas that are found today in the Galapagos Islands. Over a relatively short period of time, however, these ancestral mosasaurs became larger and more specialized, evolving rapidly into several genera of highly successful predators. By the beginning of Coniacian time (about 90 million years ago - mya), there were three major genera (Tylosaurus, Platecarpus and Clidastes) living in the Western Interior Seaway. Tylosaurs - by the Campanian, Tylosaurs were even larger (13-14 meters) and many more species were making their appearance. Within the space of a few more million years, by Maastrichtian time (70 mya), mosasaurs were truly huge, with several lineages (Mosasaurus and Hainosaurus – a close relative of Tylosaurus) reaching nearly 15 meters (50 feet). One giant specimen (Hainosaurus bernardi) found in Europe was 17 meters (almost 55 feet) in length. There was no doubt who were the biggest and baddest predators in the oceans 70 million years ago. Mosasaurs - Cretaceous Sea Dragons [USEMAP] [USEMAP] 71 Saurischia-plazopánví Ornitischia - ptakopánví [USEMAP] Dinosauria Aves •Relationships among fossil and living reptiles and birds Reptiles and Birds 2561_1508 [USEMAP] Sauriurae (oposite birds) - ? Archeopteryx(Jurrasic),Confuciusornis (Jurrasic-Cretaceous) Ornithurae (modern birds) – Hesperornis, Ichtyornis (Cretaceous) [USEMAP] [USEMAP] Euryapsids Euryapsid Include Ichthyopterygia and Sauropterygia (nothosaurs and plesiosaurs). convergence, not common ancestry; derived from diapsid.] Sauropterygia – Placodontia Notosauria Plesiosauria [USEMAP] Euryapsid Marine reptiles 24_09 Placodonts (Triassic) 1) Short-necked, body < 2m 2) sea floor dwellers 3) Crushed shellfish for food Nothosaurs (Tr-J) 1) Contemporary with placodonts 2) Streamlined bodies elongated necks 3) Ancestral to plesiosaurs Plesiosaurs 1) Found in Jurassic and Cretaceous rocks 2) Short bodies, flipperlike limbs, and long necks 3) Ate fish. Up to 12 meters in length Icthyosaurs Tr to Late K, long snouts, fishlike bodies like sharks and dolphins; convergent evol. Rapid swimmers laying eggs on land impossible live young at sea Mosasaurs (Cretaceous) 1) Giant marine lizards up to 15 meters long 2) Flattened tails and flipperlike limbs 3) Ate fish and cephalopods Plus Marine Crocodiles [USEMAP] [USEMAP] [USEMAP] Ichthyosaurs and plesiosaurs had inhabited the oceans since the Triassic, evolving into many diverse forms and surviving several major extinction events. For unknown reasons, ichthyosaurs declined significantly in early Cretaceous and are thought to have been extinct by the time that the earliest mosasaurs re-entered the water. Plesiosaurs were also less numerous in the late Cretaceous than during the Jurassic, and had evolved into some very specialized forms like the long-necked Elasmosaurus (13.7 meters). Even the short-necked plesiosaurs (pliosaurs) were much smaller than their Jurassic cousin, Liopleurodon, and an early Cretaceous relative, Kronosaurus (10m). It is possible that both the ichthyosaurs and the plesiosaurs were losing the evolutionary battle of "who eats who" to faster, giant Ginsu sharks (Cretoxyrhina mantelli). The world-wide domination that mosasaurs in the late Cretaceous. [USEMAP] [USEMAP] Synapsids Therapsida Mammalia [USEMAP] mammalogy_fig4_2 Geological Time and the Evolution of Mammals: Pelycosaurs Therapsids Cynodontia: the transitional Infraorder Mammals Fig 4.2, Feldhamer [USEMAP] Diagram showing the relationships between the various mammal-like reptiles - illustrator : Cedric Hunter (49110 bytes) Diagram showing the relationships between the various mammal-like reptiles. Mammal-like reptiles did not survive beyond the end of the Triassic period, but one group, the Cynodontia, gave rise to the first mammals at the end of the Triassic, about 200 million years ago [USEMAP] Mammals obr Prototheria (Vejcorodí) Theria (Živorodí) [USEMAP] evolution2 [USEMAP] 43 Monotremata •Oviparous egg laying mammals •Only 3 in existence •Duck-billed platypus and two species of spiny anteaters called echidna. •Not completely endothermic (their body temperature is lower and fluctuates more than other mammals) • http://members.optusnet.com.au/~alreadman/Echidna1-AR.jpg Ježura [USEMAP] 44 Marsupials •Marsupials give birth to tiny immature young that crawl to a pouch on the mothers belly immediately after they are born. • • • clip0047 [USEMAP] 45 Characteristics of Placentals •Placental mammals carry unborn young in the uterus until young can survive in the wild. •Oxygen and nutrients are transferred from mother’s blood to baby’s blood T049992A[1] [USEMAP] [USEMAP]