WILD 3580 1st Edition Lecture 18Outline of Last Lecture I. Frog calls II. ReproductionIII. Parental Investment Outline of Current Lecture I. Order CaudataII. Reproduction Current LectureI. Order Caudata- Characteristics1. Paedomorphosis/ paedogenesisa. 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 II. 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 nourishmento 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 internallyo 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 eggsa. Ex. Mudpuppies hydrate eggs 2. Egg/nest guarding- defend eggs against conspecifics a. Ex. Red-back salamander guards
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