WILD 3580 1st Edition Lecture 18 Outline of Last Lecture I Frog calls II Reproduction III Parental Investment Outline of Current Lecture I Order Caudata II Reproduction Current Lecture I II Order Caudata Characteristics 1 Paedomorphosis paedogenesis a Paedomorphosis paedo child and morph form i Retention of ancestral juvenile characteristics in a descendent adult species interspecific ii Ex External gills keeled tail sexual maturity in larval stage Mexican Axolotl b Paedogenesis neoteny intraspecific phenomenon in which partially metamorphosis occurs but some juvenile traits are retained i In individuals of a species that typically has a terrestrial adult form ii Ex Tiger salamanders Eastern Newts 2 Reduction in lungs a Family Plethodontidae lungless salamanders i Largest group of salamanders ii Hyobranchial apparatus used to protrude the tongue instead of functioning as a breathing device Reproduction Internal Fertilization courting rituals pheromones o Males deposits a spermatophore a gelatinous mass that encloses the sperm These notes represent a detailed interpretation of the professor s lecture GradeBuddy is best used as a supplement to your own notes not as a substitute o Female places it in the cloaca Oviparous lay eggs outside the body where the yolk is a source of nourishment o Most salamanders ex Spotted salamander Egg masses in water Gilled larvae are aquatic o Terrestrial species ex Red back salamander Lay eggs in a moist environment Eggs will hatch into mini adults skip larval stage Ovoviviparous retain eggs internally o Ex European salamander produces 20 eggs Eggs hatch internally and released into the water Viviparous bear live young no eggs o Ex Alpine salamander produces only 2 fertilized eggs other 18 eggs are food sources for the young nutritive eggs o Cold Climate Hypothesis retain offspring internally to protect them from the cold unpredictable conditioning increase survival fitness Embryonic development temperature dependent o Ex Pacific Giant Salamander 275 days o Ex Mole Salamanders 13 days Parental Investment amount of energy a parent spends to invest in producing protecting offspring o Strategies 1 Egg nest attendance stay with nest provide care to the eggs a Ex Mudpuppies hydrate eggs 2 Egg nest guarding defend eggs against conspecifics a Ex Red back salamander guards eggs
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