Phylum Arthropoda: Class Insecta

ChordataCampbell et al., Chapter 34Principles of Biology I (Biology 113) Notes, 2014

So God created the great creatures of the sea and every living and moving thing with which the water teems, according to their kinds, and every winged bird according to its kindGod made the wild animals according to their kinds, the livestock according to their kinds, and all the creatures that move along the ground according to their kinds. And God saw that it was good.Genesis 1:21, 25

Chordate characteristics chordates have all 4 of the following characteristics at some point in their life time: 1. Notochord: flexible rod between the digestive tube and nerve cord 2. Dorsal, hollow nerve cord: other phyla have solid cords, usually ventral 3. Pharyngeal slits: pharynx area slits 4. Muscular, postanal tail: exclusive to chordates

Lancelets (Cephalochordata) adult lancelets are weakly swimming, fish-shaped filter-feeder adults possess all four chordate characteristics (only group)

Tunicates (Urochordata) tunicates or sea squirts commonly adhere to rocks, docks and boats

have siphons for filter feeding--shoot a jet of water through excurrent siphon if disturbed

adult only has pharyngeal slits - all 4 chordate traits in larva

Subphylum Craniata Craniates chordates with a head during development dorsal hollow nerve cord topped by a neural crest backbone, cranium significance: cephalization, sophisticated neural-muscular systems adult vertebrates tend to lack pharyngeal slits, notochorda few even lack a tail

Craniate Classification: Key Dividing Points Head Vertebral column Jaws Lungs Lobed fins Legs Amniotic eggs Milk

The Jawless Ones

Class Myxini: hagfishes Skull made of cartilage, no vertebrae Segmental muscles work against notochord, retained in adulthood

Class Petromyzontida: lampreys scourge of the Great Lakes--invaded via the canal system and: decimated fish populations

feed by clamping on to fish as parasites

Jaws

Class Chondrichthyes: have cartilage endoskeletons unlike arthropod side-to-side jaws, vertebrate jaws work up and down feeding habits vary from aggressive carnivores (e.g., tiger shark, great white shark) to plankton feeders feeders (e.g., whale shark, worlds largest fish) internal fertilization; some species give birth to live young

Class Osteichthyes bony fish = largest vertebrate class with over 30,000 species cartilage hardens into bone as fish develop unlike sharks, buoyancy aided by a gas-filled swim bladder fusiform body-shape very efficient for swimming (up to 80 km/h)

Pacific Salmon recognize birthplace by smell, after 2-4 years at sea Coho most endangered; Salmon River is an indicator stream for _____Class Amphibia Amphibia means two lives Metamorphosis Therefore, If anyone is in Christ, he is a new creation; the old has gone, the new has come! (2 Corinthians 5:17)

The Frog Story eggherbivorous tadpoleslose tail, gain legsinsectivorous adult adults breath air and most possess lungs, also respire through skin many must maintain moist skin, live in moist habitatsCane Toad Curse cane toads introduced to Australia from Hawaii to control grubs attacking cane fields cane toads rapidly became one of Australias worst pests! https://www.youtube.com/watch?v=4mvV8OT-mmE

Frogs in hot water In past 25 years, zoologists have observed a rapid and alarming decline in amphibians Why?1. environmental degradation2. spread of a pathogenic chytrid fungus

Class Reptilia distinguished from amphibians by amniotic eggs which protects embryos from dehydration

The Dinosaur Story according palaeontologists, dinosaurs ruled the earth during the Mesozic Era 200-65 million years ago recent debate about whether dinosaurs were warm-blooded other new ideas: parental care, e.g., Maiasaura good mother lizard

Modern Reptiles Four groups: 1. Lepidosaurs include tuataras, and lizards and snakes 2. Turtles shell, longevity; sea turtles only come ashore to lay eggs 3. Alligators and crocodiles (crocodilians) among largest living reptiles 4. Birds the modern dinosaurs

Birds

Almost every feature adapted to flight: No urinary blader Only one ovary Small gonads Toothless beak Wings and keel Feathers Endothermic metabolism Air sacs for efficient respiration Acute vision

Bird Origins Cladistic analysis show birds should be classed within theropods (bipedal saurischian dinosaurs) So technically, dinosaurs are not extinct 10,000 species still exist today as birds Chinese paleontologists found many feathered theropod fossils since the late 1990s

Flight evolution? 1) Small, running dinosaurs gaining lift to escape predators or chase prey2) Extra traction for running up hills3) Gliding from tree branches Earliest known bird = Archaeopteryx, dating from 150 million years ago Still possessed teeth, claws on wings, many vertebrae on tail Archaeopteryx as an apparent example of a transitional fossil between reptiles and birds has created considerable controversy One of the most outspoken critics of this status is Duane Gish author of Evolution: Challenge of the Fossil Record (1985) and Evolution: The fossils still say NO! (1995) "Not a single intermediate with part-way wings or part-way feathers has been discovered. Perhaps this is why, with the passage of time Archaeopteryx in the eyes of some evolutionists, has become more and more 'reptile-like'! In contrast to Beddard's [1898] assessment of Archaeopteryx , some evolutionists today not only assert that this bird is undoubtedly linked to reptiles but that if clear impressions of feathers had not been found, Archaeopteryx would have been classified as a reptile. This is a gross overstatement to say the least." (Gish 1985, p. 110-111)

Penguins fly too but only underwater?

Class MammaliaKey characteristics:

5