Animal Diversity wrap-up Lecture 9 Winter 2014

Transcription

1 Animal Diversity wrap-up Lecture 9 Winter 2014

2 1 Animal phylogeny based on morphology & development Fig

3 2 Animal phylogeny based on molecular data Fig

4 New Clades 3 Lophotrochozoa Lophophore: crown of ciliated tentacles Trochophore larva Ecdysozoa Excrete external skeletons Molting (ecdysis) Fig

5 From Fishes to Amphibians 4 Lobe-finned fish fins had skeletal structure that developed into limbs Evolution of tetrapods (four limbs) 365 million years ago

6 Transitional Forms 5

7 6 Evolution of Tetrapods Fig

8 Subphylum Vertebrata: Class Amphibia 7 ~6150 species Frogs, salamanders Moist environments Egg has no shell, needs to be kept from drying out Skin acts in gas exchange, needs to be moist Many undergo metamorphosis Traits Tetrapods (four limbs) Adults have lungs See Fig

9 The Amniotes 8 Derived character: amniotic egg Use rib cage to ventilate lungs Fig

10 The Amniotic Egg 9 Extraembryonic membranes Shell function Fig

11 What are Birds? 15 Traits: Tetrapods Amniotic egg (amniotes) Wings - Feathers of keratin Bird Adaptations for flight Large sternum and strong pectoral muscles Hollow bones No teeth

12 What are Birds? 15 Reduced organs or missing organs Endotherms High metabolic rate use heat produced to maintain constant body temperatures! See figure 34.30

13 What are Birds? 11 Class Aves and Class Reptilia? Fig

14 Subphylum Vertebrata: Class Reptilia ~17,900 species of snakes, lizards, turtles, crocodiles, alligators, and birds Traits Tetrapods Ectotherms (except birds!) Amniotic egg (amniotes) Fluid filled egg in protective shell Water proof skin Scales with keratin Keratin also in feathers, fingernails 12 See figure See figure 34.30

15 Subphylum Vertebrata: Class Reptilia (Superorder Lepidosauria) Lizards, Snakes and Tuataras 13 ~7,900 species of snakes, lizards, turtles Traits Tetrapods Amniotic egg (amniotes) Fluid filled egg in protective shell Water proof skin Scales with keratin Ecototherms Do not generate their own heat, use heat from their environment See Fig

16 Subphylum Vertebrata: Class Reptilia (Order Testudines) Turtles 307 known species of species of turtles Traits Tetrapods Amniotic egg (amniotes) Fluid filled egg in protective shell Water proof skin Scales with keratin Vertebral column fused to shell Terrestrial or aquatic (both marine and fresh water) Ecototherms Do not generate their own heat, use heat from their environment 14

17 Subphylum Vertebrata: Class Reptilia (Superorder Archosauria) Birds, Crocodiles, and Alligators ~10,000 species birds 23 species alligators and crocodiles Birds descended from lineage of dinosaurs that had feathers Crocodiles and Alligators are closest living relatives to birds Traits: Tetrapods Amniotic egg (amniotes) Wings - Feathers of keratin Bird Adaptations for flight Hollow bones No teeth Large sternum and strong pectoral muscles Reduced organs or missing organs Endotherms Birds only! High metabolic rate use heat produced to maintain constant body temperatures! 15 See figure 34.30

18 Subphylum Vertebrata: Class Mammalia 16 ~5,300 species Rapid diversification ~ 65 myo (end of age of the reptiles ) Traits Tetrapods Amniotic egg (most w/o shell) Mammary glands Hair Endotherms Three main group Monotremes (egg laying mammals) Only 2 species (duck-billed platypus, echidna) Marsupials ( pouched mammals) Offspring complete their development in pouches Primarily Australia & South America Eutherians (placental mammals) Offspring remain in womb