1 / 15

Lecture 34 : Cenozoic Life Volant Organisms

Lecture 34 : Cenozoic Life Volant Organisms. Holocene representatives of Accipitriformes (birds of prey). Subdivisions of the Cenozoic Era (Phanerozoic Eon). Originally based on the similarities of the fossil faunas to modern-day faunas.

desimonej
Download Presentation

Lecture 34 : Cenozoic Life Volant Organisms

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Lecture 34: Cenozoic LifeVolant Organisms Holocene representatives of Accipitriformes (birds of prey)

  2. Subdivisions of the Cenozoic Era (Phanerozoic Eon) Originally based on the similarities of the fossil faunas to modern-day faunas. Most extant mammal groups have their origins in the Cenozoic (especially the Eocene).

  3. Cenozoic Climate Marine floras and faunas change with climate.

  4. As continents continue to separate during the Cenozoic: Marine organisms can radiate (drifting or active swimming with ocean currents) Terrestrial faunas become more and more isolated… Volant organisms?

  5. Distribution route of Cenozoic terrestrial organisms? * North America * Atlantic Ocean Africa Distribution route of Paleogene marine organisms? South America Eocene Epoch (45 Ma)

  6. Pleistocene faunal interchange between North & South America Isthmus of Panama Occasional land bridges unite land masses, allowing for dispersal elsewhere.

  7. Although varied in structure, homologous organs point to common acestry among vertebrate groups

  8. Convergence among distantly related vertebrate groups – Mesozoic marine reptiles and Cenozoic marine mammals

  9. Most birds are volant, although some secondarily flightless Diatryma Volant Archosauria - Aves 10,000 extant species Phorusrachids – “terror birds”

  10. Bird flight – from the ground up?

  11. General bird skeleton Characterized by: Lightweight bones – hollow and thin-walled (easy to destroy) Many bones fused into one structure Toothless beak

  12. Birds of Fossil Lake (Wyoming) lived on and around Eocene freshwater lakes Pseudocrypturus cercanaxius Gallinuloides wyomingensis Galliformes (turkey, chicken, pheasant) ostrich relative

  13. Fossil Lake Lk. Gosiute Lk. Uinta early Eocene (48 Ma) midcontinent USA – huge freshwater lakes

  14. Fossil birds of Messel (Germany) lived on and around Eocene freshwater lakes Palaeoglaux sp. Rhynchaeites messelensis Ciconiformes (storks, herons, ibis) Messelornis cristata Gruiformes (cranes & rails) Strigiformes (owls)

  15. early Eocene (47 Ma) environment – Messel, Germany Stages in the formation of the Messel lakes

More Related