1 / 39

Evolution of the Amniotes: From Ancestral Condition to Diverse Species

Explore the monophyletic origin and skeletal characteristics of early amniotes, from Seymouria to Diadectomorphs, evolving into truly terrestrial beings. Uncover the function of amniotic membranes, fertilization, and development in the evolution towards amphibian ancestors. Discover the diapsids, anapsids, and the unique adult features of turtles in the late Triassic period, with 280 morphologically homogeneous species exhibiting ecological diversity in habitat, trophic relations, and reproduction.

glaze
Download Presentation

Evolution of the Amniotes: From Ancestral Condition to Diverse Species

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. Evolution of the amniotes

  2. Evolution of the amniotes • monophyletic • the unifying synapomorphy… • the terrestrial environment… • truly terrestrial • function of membranes? • fertilization? • development?

  3. Evolution of the amniotes • Skeletal characteristics of early amniotes: • palatoquadrate… • anterior epipterygoid and posterior quadrate • articular bone… • articulates with quadrate • fenestra ovalis… • atlas/axis…

  4. Ancestral anamniote condition gut wall posterior anterior YS embryonic coelom body wall

  5. Initial stage of development developing amniotic folds

  6. Later stage of development ch

  7. Derived amniote condition Derived Amniote Condition

  8. Evolution of the amniotes Diadectomorphs Seymouriamorphs amniotes reptilomorph ancestor

  9. Seymouria…

  10. Diadectomorphs

  11. Evolution of the amniotes synapsids diadectomorphs Seymouria amniotes reptilomorph ancestor

  12. Evolution of the amniotes diapsids anapsids synapsids diadectomorphs Seymouria amniotes reptilomorph ancestor

  13. Diapsids

  14. Diapsids

  15. Diapsids

  16. Diapsids

  17. Diapsids

  18. Diapsids

  19. Anapsids… The Turtles late Triassic… …fully formed 280 species morphologically homogeneous

  20. carapace plastron bridges scutes reduced…

  21. vertebral column and ribs… pectoral girdle and sternum… plastron hinged external and internal nostrils “beak”

  22. ecologically diverse… habitat… trophic relations…

  23. oviparous… burrows… eggs… temperature… predation…

  24. 3 snapper stories…

  25. Loggerhead sea turtles Caretta caretta

  26. green sea turtles

  27. waves…

More Related