New User Special Price Expires in

Let's log you in.

Sign in with Facebook


Don't have a StudySoup account? Create one here!


Create a StudySoup account

Be part of our community, it's free to join!

Sign up with Facebook


Create your account
By creating an account you agree to StudySoup's terms and conditions and privacy policy

Already have a StudySoup account? Login here

Midterm Study Guide

by: Sierra

Midterm Study Guide FNR 251


Preview These Notes for FREE

Get a free preview of these Notes, just enter your email below.

Unlock Preview
Unlock Preview

Preview these materials now for free

Why put in your email? Get access to more of this material and other relevant free materials for your school

View Preview

About this Document

These notes are going to be covered on the midterm
Ecology And Systematics Of Amphibians, Reptiles, And Birds
Rod N. Williams
Study Guide
Ecology, systematics, amphibians, reptiles, forestry, Natural Resources
50 ?




Popular in Ecology And Systematics Of Amphibians, Reptiles, And Birds

Popular in Agriculture and Forestry

This 334 page Study Guide was uploaded by Sierra on Monday February 29, 2016. The Study Guide belongs to FNR 251 at Purdue University taught by Rod N. Williams in Spring 2016. Since its upload, it has received 86 views. For similar materials see Ecology And Systematics Of Amphibians, Reptiles, And Birds in Agriculture and Forestry at Purdue University.


Reviews for Midterm Study Guide


Report this Material


What is Karma?


Karma is the currency of StudySoup.

You can buy or earn more Karma at anytime and redeem it for class notes, study guides, flashcards, and more!

Date Created: 02/29/16
LECTURE 1: Amphibian and Reptile Evolution The Origin and Evolution of Amphibians (Lissamphibia) Lissamphibia Why land? • Unexploited food resources – Aquatic habitat niches occupied – No predators on land, lots of food sources • Lack of Large Terrestrial Predators – primitive plants & invertebrates • Low O 2n warm water Early T etrapods • Addition of Teeth • Paired fins to limbs • Gills replaced by lungs Early T etrapods • Increased skeletal support • Tongue – increased sensory • Larynx for vocalization • Larger cerebral cortex II. PHYLOGENY: AMPHIBIANS Source: Vertebrate Biology, D. Linzey, 2001. Era and Period Names and their duration in MYA Era Period begin - end (MYA) Extant Quaternary 23.0 - 0.00 Salamanders Cenozoic & Frogs Tertiary 65.5 - 23.8 Cretaceous 146 - 65.5 Mesozoic Jurassic 200 - 146 Triassic 251 - 200 Permian 299 - 251 Carboniferous 359 - 299 Devonian 416 - 359 Paleozoic Silurian 444 - 416 Ordovician 488 - 444 Cambrian 542 - 488 II. PHYLOGENY: AMPHIBIANS Tiktaalik Eryops FNR 251 01/7/2008 Origin of Salamanders Tiktaalik • Late Devonian (375 mya) – Canada • 2004 Discovery • Pre-dated Ichthyostega by 5 my. • 1-2 meters long Tiktaalik • Most remarkable feature: front pair fins with wrist-like structure • Spiracles (primitive nostrils) – lungs as well as gills • 1 tetrapod with: proper neck enabling greater flexibility during short bouts on land Ichthyostega • Late Devonian (370mya) • Greenland, “roof fish” • 5 ft, 50 lbs • Fish & Amphibian features – Webbed feet • Ability to breathe air for short periods Eryops • Permian (270mya) • Crocodile-like early amphibian • Aquatic & Terrestrial • Structurally, some features that would appear in later reptiles Diplocaulus • Middle late Permian (240-230mya) • Greek “double stalk” • Wide V shaped boomerang head – Navigate strong currents – Facilitate rapid opening for suction-gape feeding • 3 ft long, 5-10 lbs Modern Salamander Families • Amphiumidae, Sirenidae: Upper Cretaceous • Cryptobranchidae, Protidae, Salmandridae: Paleocene • Plethodontidae: Pleistocene The Origin of Anura Frog Evolution Trends • Modifications for jumping: – Vertebral column short and inflexible • Reduction Presacral vertebrae • Increase rigidity, absorption of landing • Transfer Energy directly to hindlimbs – Hindlimbs elongated for hopping – Muscles modified for jumping Frog Evolution Trends • Modifications for jumping: – Pelvic girdle enlarged, strengthened, and anchored to vertebral column – No ribs – No tail as adult – Overall body truncated Amphibamus • Late Carboniferous (300mya) • Greek for equal legs • Swamps: Europe & N. America • 6 in, few ounces • 33 Presacral vertebrae Gerobatrachus • Early Permian (290mya) 2008 – Texas • “frogmander”: mixture salamander & frog – 2 fused ankle bones – Backbone intermediate – Large tympanum – Wide froglike skull • Likely transitional form – 240-275 mya splitting frogs and salamander Triadobatrachus • Early Triassic (250mya), Madagascar • Triple frog • “Proto frog” • First fossil “frog” Vieraella • Early Jurassic (~200 mya) – Argentina – Earliest “true” frog • May belong to modern family Leiopelmatidae • Classic froglike head & large eyes • legs modified for jumping Triadobatrachus Vieraella Tibiofibula urostyle Paleobatrachus • Cretaceous to Tertiary (130-5 mya) • “ancient frog”, Europe • Completely aquatic – inhabited swamp basins – Volcanic gases preserved soft tissue • Resembles present day Xenopus Extant Amphibian Lineages LECTURE 2: TAXONOMY WITH CHARACTERISTICS: AMPHIBIANS American Toad Anaxyrus americanus Review of Terms: Lecture 2  Anatomical Features: Costal groove, Dorso-lateral folds, Naso-labial groove, Parotid glands  Reproductive and Developmental Terms: Amplexus, External fertilization, Eft, Explosive breeder, Aggregate breeder, Internal fertilization, Neotenic development, Tadpole  Habitat Term: Fossorial General Information for Each Taxonomic Group Morphological characteristics Habits & Habitat Reproduction & Development Diet Geographic distribution: Present in Indiana? Conservation status  Photographs of representative species I. Order Gymnophiona: Caecilians Ichthyophis kohtaoensis Purple Caecilian (Gymnopis multiplicata) II. Order Caudata (or Urodela): Salamanders II.c. Salamanders: Family Sirenidae (“Sirens”) Paedomorphic We(Siren intermedia) II.a. Salamanders: Family Cryptobranchidae Eastern Hellbender Cryptobranchus alleganiensis ENDANGERED II.b. Salamanders: Family Proteidae (“Mudpuppies”) Mudpuppy or Waterdog (Necturus maculosus) II.d. Salamanders: Family Ambystomatidae (“Mole Salamanders”) Eastern Tiger Salamander (Ambystoma tigrinum) (Ambystoma maculatum) II.e. Salamanders: Family Plethodontidae (“Lungless Salamanders”) Four-toed Salamander (Hemidactylium scutatum) ENDANGERED Green Salamander (Aneides aeneus) ENDANGERED II.f. Salamanders: Family Salamandridae (“Newts”) Central Newt A (Notophthalmus viridescens louisianensis) B B A Red-spotted Newt: (Notophthalmus viridescens viridescens) A) Eft B) Adult Anuran Diversity • Currently 45 families • ~ 5,500 species • Taxonomy is constantly changing – Species discoveries – Genetic technologies III. Order Anura: Frogs and Toads Cranial Crests Dorso-lateral Fold No Fold Parotid Glands Warts Tympanum Dorso-lateral Fold Toepads Parotid Gland III.e. Frogs and Toads: Family Leiopelomatidae (“Tailed Frog”) (Ascaphus truei) III.d. Frogs and Toads: Family Scaphiopodidae (“Nearctic Spadefoot Toads”) (Scaphiopus holbrookii) SPECIAL CONCERN III.b. Frogs and Toads: Family Hylidae (“Tree Frogs”) III.b. Frogs and Toads: Family Hylidae (“Tree Frogs”) III.g. Frogs and Toads: Family Centrolenidae (“glass frogs”) III.a. Frogs and Toads: Family Bufonidae (“Toads”) A American Toad (Anaxyrus americanus) Marine Toad (Rhinella III.c. Frogs and Toads: Family Ranidae (“True Frogs”) Bullfrog (Lithobates catesbeianus) III.f. Frogs and Toads: Family Dendrobatidae (“poison frogs”) Golden Poison Frog (terribilis) LECTURE 3: Origin of Reptiles Reptiles: Taxonomy and basic characteristics • Increasing modifications to land – Limbs, muscles – Increasing brain size (cerebrum and cerebellum) – More effective jaw – Skeletal structure improved – Skin tough covered with scales – Well developed lungs – Amniote egg Era and Period Names and their duration in MYA Era Period begin - end (MYA) Quaternary 23.0 - 0.00 Cenozoic Tertiary 65.5 - 23.8 Cretaceous 146 - 65.5 Mesozoic Jurassic 200 - 146 Triassic 251 - 200 Permian 299 - 251 Carboniferous 359 - 299 Devonian 416 - 359 Paleozoic Silurian 444 - 416 Ordovician 488 - 444 Cambrian 542 - 488 II. PHYLOGENY: AMPHIBIANS Eryops FNR 251 01/7/2008 II. PHYLOGENY: REPTILES FNR 251 01/7/2008 Early Reptiles • A: Anapsid, 1 Reptiles – no temporal fenestrae • B: Synapsid – Mammal-like reptiles, mammals • C: Diapsid – Larger, stronger jaw muscles – Crocs, Snake, Lizard, Tuatara – Extinct dinosaurs, pterosaurs, icthyosaurs – Disagreement=Turtles (anapsid type) II. PHYLOGENY: REPTILES FNR 251 01/7/2008 Early Reptiles: Amniotes • Casineria: Early Carboniferous (340mya) – Salamander-like early tetrapod – 5 digits with claws – 1 amniote, Ancestor to amniotes • Amniotes: – Eggs survive out of water – Disperse onto drier land st 1 Lizards, Hylanomus • Carboniferous (315 mya) – Canada • Perhaps earliest known reptile – Among first amniotes, anapsid – Small, lizard-like (8-12 in) – Fossil with distinct toe & scales • Numerous sharp teeth – Insectivorous diet Mesozoic “Age of the Reptiles” • Explosive Radiation of Reptiles – Most numerous & largest • Dominant Terrestrial & Aerial Animals – Also Formidable marine predators Archosauromorphs • “Ruling Reptiles” of Mesozoic – Early Diapsid amniotes • Ancestral to Crocodilians, Birds, Turtles • Euparkeria: ancestry of Archosauromorphs – From Early Triassic – resembled Short necked monitor lizard – Dermal bone armor – Part of lineage leading to Dinosaurs Crocodylians • Surviving Archosaurs • Early ancestors – Jurassic to mid Cretaceous • Stomatosuchus – ~36ft, swamps, N. Africa • Sarcosuchus – “Flesh crocodyle”, ~40ft – Super Croc Lepidosauromorphs • 2ndMajor Diapsid lineage – Ancestral to Squamates (Lizards, Snakes), Tuatuara • First Appear late Permian Tuatuara, Sphenodontia • Living Fossils: Triassic, • Descended from beak-headed reptiles, Rhinocephalia • 1 Sphenodontian: Brachyrhinodon taylori – Europe – Similar to modern Tuatuara – Exception: skull more broad, robust • Extant: Endemic to new Zealand Anapsids: turtles • Triassic: – Basic body plan – Odontochelys – Proganochelys • Jurassic: – Eileanchelys • Cretaceous: – Archelon Odontochelys • Late Triassic (220 mya) – E. Asia, shallow marine waters near shore • 2008, Predates Proganochelys by 10 mys. • “toothed shell” Proganochelys • Late Triassic (210mya) – Prior to 2008, most well known • “early turtle” • 3 ft., ~75 lbs • Possess few teeth – Modern turtle lack Eileanchelys • Late Jurassic (165-160 mya) – W. Europe (Scotland) • Earliest pond turtle • 2008 Discovery Archelon • Late Cretaceous (75-65 mya) – Oceans of N. America • “Ruling turtle” – 12 ft., ~2 tons • Large flipper-like arms & legs • Leathery Shell • Closest living relative: Leatherback Lizards Review of Terms: Lecture 1,3 All Era, Period, and Epoch Names Anapsids, Diapsids, Synapsids Anurans, Caecilians, Caudata Crocodylia, Lacertilia, Squamata, Testudines Archosaur Anthracosauria, Ichthyostega, Lissamphibia Archosurians, Lepidosaurus Tetrapods LECTURE 4: TAXONOMY WITH CHARACTERISTICS: REPTILES Alligator mississippiensis General Information for Each Taxonomic Group Morphological characteristics Habits & Habitat Reproduction & Development Diet Geographic distribution: Present in Indiana? Conservation status  Photographs of representative species I. Order Testudines (or Chelonia) Turtles Ventral View Dorsal View PLASTRON CARAPACE I.a Order Testudines: Families Cheloniidae and Dermochelyidae (Sea Turtles) Atlantic Leatherback Sea Turtle (Dermochelys coriacea coriacea) I.b Order Testudines: Families Chelydridae (Snapping Turtles) Alligator Snapping Turtle (Macroclemys temmincki) ENDANGERED Common Snapping Turtle (Chelydra serpentina serpentina) I.c Order Testudines: Families Kinosternidae (Mud and Musk Turtles) Eastern Mud Turtle (Kinosternon subrubrum subrubrum) ENDANGERED I.d Order Testudines: Families Emydidae (Basking, Marsh, and Box Turtles) Ornate Box Turtle (Terrapene ornata ornata) ENDANGERED FNR 251 01/11/2008 I.e Order Testudines: Families Testudinidae (Tortoises) (Gopherus agassizii) I.e Order Testudines: Families Trionychidae (Soft-shelled Turtles) Eastern Spiny Softshell (Apalone spinifera spinifera) II.b Order Crocodylia: Families Crocodylidae and Alligatoridae (Alligators and Crocodiles ) Croco(fossil)eoderm American Alligator American Crocodile (Alligator mississippiensis) (CENDANGEREDacutus) III.a Order Squamata : Suborder Lacertilia (Lizards) Typical Lizard Claws Scales (Salamanders have smooth skin) No Claws Underside of Thigh Salamander Femoral Pores Foot Movable No movable Eyelids Eyelids Ear No Ear Openings Opening Lizard Snake FNR 251 01/11/2008 III.b Suborder Lacertilia: Family Gekkonidae (Geckos) Uroplatus henkeli Uroplatus phantasticus III.c Suborder Lacertilia: Family Iguanidae (Iguana) Galápagos Marine Iguana Ctenosaura hemilopha (short- (Amblyrynchus cristatus) crested spiny-tailed iguana) Phrynosomatidae (spiny lizards) Northern Fence Lizard (Sceloporus undulatus) Texas Horned Lizard (Phyrnosoma cornutum) Agamidae Chlamydosaurus kingii Moloch horridus frillneck lizard The Thorny Devil Bearded Dragon (Pogona Vitticeps) Polychrotidae (anoles and friends) III.d Suborder Lacertilia: Family Anguidae (Glass or Alligator Lizards) Western Slender Glass Lizard (Ophisaurus attenuatus attenuatus) III.e Suborder Lacertilia: Family Helodermatidae (Beaded Lizards) From top to bottom:An adult, a two year-old and a Mexican Beaded Lizard (Heloderma horridum) Size Comparison: Male on the left, Female on the right. III.f Suborder Lacertilia: Family Teiidae (Whiptails and Racerunners) Prairie Racerunner Six-lined Racerunner (Aspidoscelis sexlineatus (Aspidoscelis sexlineatus) FNR 251 01/1viridis) III.g Suborder Lacertilia: Family Scincidae (Skinks) Five-lined Skink Ground Skink (Plestiodon fasciatus) (Scincella lateralis) IV. Order Squamata : Serpentes (Snakes) Female: Tapers from Anus Male: Stout at base Stump-tail: Lost via accident IV.a Order Squamata : Family Boidae (Boas) Amazon Basin Emerald Tree Boas Boa constrictor (Corallus caninus) IV.b Order Squamata : Family Viperidae (Vipers) Eastern Massasauga RattlesnakeTimber Rattlesnake (Sistrurus catenatus caten(Crotalus horridus horridus) FNR 251 ENDANGERED ENDANGERED IV.c Order Squamata : Family Elapidae (Cobras, Coral) Western Coral Snake Harlequin Coralsnake (Micruroides euryxanthus)icrurus fulvius) IV.d Order Squamata : Family Colubridae(Snakes) IV.e Order Squamata : Family Natricidae (Snakes) Kirtland’s Snake (Clonophis kirtlandii) ENDANGERED Redbelly Water Snake (Nerodia erythrogaster) ENDANGERED IV.f Order Squamata : Family Dipsadidae(Snakes) Review of Terms: Lecture 3 Anatomical Features: Aposematic coloring, Carapace, Cloaca, Hemotoxin, Jacobson’s Organ, Neurotoxin, Osteoderms, Plastron Reproductive and Developmental Terms: Temperature-dependant sex determination, Oviparous, Ovoviviparous, Viviparous LECTURE 5: ENERGETICS AND METABOLISM THE ECTOTHERMIC LIFE IMPORTANT TERMS Activity Temperature Range Mean Activity Temperature Operative Temperature Homeothermy Acclimation Thermoregulation INTRODUCTION Ectothermic: Reptiles & Amphibians Primary heat source is external Heat is not always available More economical Endothermic: Birds & Mammals Primary heat source is internal Do better in cold environments More expensive I.a. Basic Energetics: Energy Budget Source: HerpetoloEdition. Zug, Vitt, and Caldwell. 2001. I.b. Basic Energetics: Energy Budget Painted Turtle (Chrysemys picta) II. a. Thermal Interactions and Heat Exchange in Ectotherms Heat exchange with the environment occurs via: Radiation Convection Conduction II. b. Thermal Interactions and Heat Exchange in Ectotherms SURFACE AREA VS. VOLUME LENGTH SURFACE VOLUME OF SIDE (cm) AREA (cm ) (cm ) RATIO 1 6 1 6:1 4 96 64 1.5:1 10 600 1,000 0.6:1 20 2,400 8,000 0.3:1 II. c. Thermal Interactions and Heat Exchange in Ectotherms Source: HerpeEdition. Zug, Vitt, and Caldwell. 2001. II. d. Heat Exchange: Aquatic Amphibians Source: HerpetologEdition. Zug, Vitt, and Caldwell. 2001. II. e. Heat Exchange: Terrestrial Amphibians II. f. Heat Exchange: Reptiles II. g. Heat Exchange: Secretive/Nocturnal Amphibian & Reptiles Source: HerpetEdition. Zug, Vitt, and Caldwell. 2001. III. a. Temperature Ranges and Tolerances Examples of Body Temperatures (°C) FNR 251 01/18/2006 nd III. b. Temperature Ranges and Tolerances Active Body Temperature (ATR) varies depending on: Taxa Habitat Season Genetics For most the range is between 27°C and 35°C (few reptiles have ATRs < 20°C) IV. a. Regulation of Body Temperature Regulation of body temperature is due largely due to behavioral adaptations Amphibians (terrestrial) handle regulation differently because of moist skin: Low resistance to water loss Tb largely tracks Te (but a couple of degrees cooler due to evaporation) Reptiles can be exposed to sunlight without excessive water loss IV. b. Regulation of Body Temperature Other physiological / morphological adaptations: Adjustment of blood flow to skin Adjustment of heart rate Color changes Special adaptation seen in leatherback turtles IV . c. Regulation of Body Temperature Spiny Softshell (Apalone spinifera) IV. d. Regulation of Body Temperature Regulation of Body Temperature Through Behavioral Adaptations V. a. Dormancy Dormancy: response to temperature extremes, usually hot and dry in deserts, freezing or below in temperate regions: Scaphiopus active 1 month/year in Arizona Thamnophis for 4 months/year in Manitoba Dormancy can occur in three different forms: Hibernation Freeze Tolerance Estivation V. b. Dormancy 1. Hibernation: Tb largely allowed to track Te, except that metabolic activities slowed even more than “normal” for a given temperature Animals move during hibernation Aquatic hibernation V. c. Dormancy 2. Freeze tolerance: Freezing is lethal to all but a few species (ice crystals destroy cells and extracellular fluid freezes and dehydrates cells) A few species (e.g., Hyla crucifer) are “freeze-tolerant” and survive extracellular freezing V. d. Dormancy 3. Estivation: Animals inhabiting desert and semidesert environments Physiology is not well known Animals retreat to deep burrows with high humidity and moist soils and reduce their metabolism All life process (breeding, etc) are greatly accelerated in these species Review of Terms: Lecture 5 Active Body Temperature (ATR) Conduction, Convection, Radiation Dormancy, Estivation, Freeze Tolerance, Hibernation Ectothermic, Endothermic, Homeothermic Energy Budget Inertial Endothermy Surface Area LECTURE 6: PHYSIOLOGY & SENSORY SYSTEMS I. Basic Physiology: Organ Systems Circulatory System Respiratory System Sensory System and Organs (Reproductive and Digestive systems covered in other lectures) I.a. Amphibian Circulatory System Circulatory System: a) Heart b) Blood vessels c) Lymphatic system I.a. Amphibian Circulatory System A. Heart: All amphibians have a three chambered heart: Two atria One ventricle Structure highly variable due to: Cutaneous Pulmonary respiration I.a. Amphibian Circulatory System A. Amphibian Heart Lung I.a. Amphibian Circulatory System C. Lymphatic Systems: Lymphatic network of vessels is an open system containing both: Lymphatic vessels Open cavities or sinuses “Lymph hearts” present in amphibians: Found at venous junctions Contractile structures with valves that prevent back-flow and speed up flow from lymph into veins I.a. Amphibian Circulatory System D. Blood: Red blood cells nucleated I.b. Reptilian Circulatory System A. Heart: No single “model” The typical reptilian heart consists of three chambers: Two atria One ventricle (divided into 3 chambers or cava) I.b. Reptilian Circulatory System A. Turtle Heart I.b. Reptilian Circulatory System A. Turtle Heart I.b. Reptilian Circulatory System B. Vessels: Blood vessels are similar to those present in adult amphibians with minor differences (adaptations) Lymph system is an elaborate drainage network of microvessels and sinuses Lymphatic hearts are present, but valves are rare (bidirectional flow) C. Blood: Red blood cells are nucleated I.c. Amphibian Respiratory System A. Lungs: Lungs similar in form to other vertebrates Air moves in and out by a buccopharyngeal force pump mechanism Some have no lungs Other surfaces for air exchange: a) Buccopharyngeal cavity b) Gills c) Skin I.c. Amphibian Respiratory System B. Breathing in Amphibians I.d. Reptilian Respiratory System A. Lungs: Reptiles also have simple sac-like lungs Small sacs (faveoli) radiate outward from large central chamber Snakes have single functional right lung (left is non-functional) I.d. Reptilian Respiratory System A. Lungs: Breathing in reptiles mostly occurs by expansion and contraction of intercostal muscles muscles Crocodilians have diaphragms as well In turtles, breathing is accomplished by abdominal and pectoral girdle muscles Other surfaces for air exchange: a) Buccopharyngeal cavity b) Skin II.a Sensory Systems and Organs Functions of Sensory system: a) Maintenance of homeostasis b) Find prey c) Escape Predators d) Find mates Sense organs are integrated to the Central and Peripheral Nervous Systems II.b Sensory Systems and Organs: Amphibians A. Cutaneous : a. Lateral line system: Aquatic species (mostly larval stages) Series of pores aligned as a “line” on head and trunk Lines are formed by neuromasts b. Other Receptors: Pain Temperature Pressure and touch (mechanoreceptors) II.b Sensory Systems and Organs: Amphibians B. Ears: Outer ears are usually absent Tympanum (ear drum) at surface Middle ear Inner ear II.b Sensory Systems and Organs: Amphibians B. Ears: Middle ear has two auditory pathways: a) Tympanum/Columella Pathway: for airborne sounds b) Forelimb/Opercular Pathway: for seismic sounds II.b Sensory Systems and Organs: Amphibians B. Ear Anatomy II.b Sensory Systems and Organs: Amphibians B. Forelimb/Opercular Pathway II.c Sensory Systems and Organs: Reptiles A. Cutaneous:  a. Pit Organs: Boas and pythons Crotalidae snakes b. Other Receptors: Pain Temperature Mechanoreceptors II.c Sensory Systems and Organs: Reptiles B. Ears: Outer ear Middle ear Inner ear II.c Sensory Systems and Organs: Reptiles C. Eyes: Large and well developed in most reptiles Pupils are circular to elliptical Most reptiles have color vision (cones) and rods Parietal eye: Pineal organ is sister organ capable of photoreception and melatonin production Capable of perceiving light and integrating photoperiod and hormone production II.c Sensory Systems and Organs: Reptiles D. Nasal Organs: Sensory area (olfaction) principally in roof and dorsal walls of nasal cavity Jacobson’s organ Found near nasal cavity and odor particles carried from tongue (oral cavity) to organ via duct E. Other Organs: Similar to those in amphibians Review of Terms: Lecture 6  Circulatory System: Atria, Cava, Lymph Hearts, Lymphatic Sinuses,Ventricle  Respiratory System: Buccopharyngeal Cavity, Cutaneous Respiration, Diaphragm, Faveoli, Intercostal Muscle, Pulmonary Respiration  Sensory System: Columella, Forelimb/opercular Pathway, Lateral Line System, Mechanoreceptors, Neuromasts, Nictitating Membrane, Parietal Eye, Pit Organs, Propioreceptors, Tympanum, Tympanun/columella Pathway, Vomeronasal Organ (Jacobson’s Organ) LECTURE 6: AMPHIBIAN REPRODUCTION, GROWTH AND DEVELOPMENT I. Reproduction and Life Histories Amphibians have evolved diverse solutions to enhance their reproductive output and offspring survival. For example: a) Amphibians display a spectacular diversity of reproductive modes b) Fertilization can occur inside or outside the body of females c) Development can be direct or indirect II. Gametogenesis and Ovulation In most amphibians, two sexes (♀♂) are needed for reproduction Gametogenesis is a major feature of sexual reproductive preparations: Involves the division and growth within the ovaries (♀) and testes (♂) through hormonal activation II. Gametogenesis and Ovulation Vitellogenesis is a very important process in egg-laying vertebrates: Accumulation of nutrients in the cytoplasm of the developing egg Rapid growth of cotocytes II. Gametogenesis and Ovulation Ovulation occurs when the follicular and ovarian walls rupture As eggs pass through the oviduct, protective membranes are deposited around them Amphibian eggs are anamniotic Eggs are expelled singly, in gelatinous masses, or strings II. Gametogenesis and Ovulation Gelatinous mass of eggs - Wood FrogTiger Salamander egg mass Eggs from an American Toad deposited as long strings III. Fertilization Fertilization is defined as the fusion of male and female gametes to form a zygote During mating, many sperm can reach the egg, but only one will penetrate it and fertilize it (exception are salamanders which have internal fertilization) Two types in amphibians: a) external III. Fertilization 1. External Fertilization: Simultaneous shedding of eggs and sperm into water  Most frogs and Crytobranchoid salamanders Constrain where the eggs are laid Frogs: males grasp females in back around legs so that his cloaca is positioned just above female’s cloaca Salamanders: amplexus may occur or males follows females depositing sperm on egg masses III. Fertilization Wood Frogs Tree Frogs Amplexus in Frogs III. Fertilization 2. Internal Fertilization: Few species of frogs, Salamadroid salamanders, and all Caecilians Allows eggs to be laid in spot and at time of choice Frogs: require special intromittent organs (hemipenis) in males for delivering sperm into female’s cloaca Salamanders: male produces sperm which are deposited externally Fertilization occurs in cloaca, but often is delayed with sperm storage in series of tubules on roof of cloaca called spermatheca III. Fertilization Spermatophore in a Salamander IV. Reproduction Without Fertilization Asexual Reproduction: reproduction occurs without the males genetic contribution, and in some taxa, populations are 100% females Two types in amphibians: a) hybridogenesis b) synogenesis IV . Reproduction Without Fertilization Bisexual and Unisexual Reproduction in Amphibians. The “B” in the offspring produced by hydridogenesis and gynogenesis comes from the mother. FNR 251 01/23/2008 IV. Reproduction Without Fertilization • “Unisexual” hybrid Ambystoma complex • ~ 5 million years ago • 5 parental species • Ploidy number varies: – 2n, 3n, 4n, 5n V. Parental Care Definition: Most amphibians show no parental care other than attendance and guarding of eggs Represented by a variety of behaviors: 1. nest egg 2. egg brooding 3. transport 4. feeding of young V . Parental Care Australian Gastric Brooding Frog (female with froglet) Mallorcan Midwife Toad (male carrying eggs on hind legs)Surinam Toad (female with eggs on back) VI. Development Important terms: Exotrophic Metamorphosis Paedomorphosis a) Progenesis b) Neoteny VII. Growth Two growth pulses a) Embryonic b) Juvenile VIII. Age A. Intervals (periodicity and not age) are important: 1. Sexual Maturity 2. Embryogenesis 3. Larval period metamorphosis VIII. Age IX. Dynamics of Reproduction Multitude of patterns geared to the right environment for offspring All temperate species are cyclic Tropical species cyclic or acyclic In temperate salamanders, two patterns: 1. Winter/spring mating and egg deposition (Ambystomatids) 2. Late summer/fall mating and spring egg deposition (Plethodontids) IX. Dynamics of Reproduction Mate attraction and selection Location usually not a problem Reproduction is more efficient within home range Courtship has communication as key Females heavy investment in gametes obligates her to select most fit male Review of Terms: Lecture 6  Gvitellogenin and vitellogenesis, Ovulation, Spermatheca,s, Spermatophore, Polyspermic  Fertilization: Amplexus, Fertilization, internal, external, Hemipenis, Paedomorphosis  Reproduction without Fertilization: Asexual reproduction, Gynogenesis, Hybridogenesis  Development and Growth: Exotrophic, Metamorphosis, Neoteny, Progenesis  Parental care LECTURE 8: REPTILIAN REPRODUCTION, GROWTH AND DEVELOPMENT American Alligator Hatchlings I. Reproduction and Life Histories Major differences of reptilian reproductive features compared to amphibians: a) Internal Fertilization b) Direct Development c) Amniotic Egg All these factors allowed reptiles to become independent of standing water for breeding II. Gametogenesis and Ovulation Vitellogenesis is a very important process in egg-laying vertebrates: a) Accumulation of nutrients b) Nutrients will later become the yolk In reptiles, vitellogenin is selectively absorbed by oocytes and enzymatically converted to yolk proteins II. Gametogenesis and Ovulation Cleidoic egg (shelled): Shell prevents desiccation and contamination by environmental pathogens Creates own aquatic environment By folding and curling, the reptile embryo can attain surprising lengths Three extraembryonic membranes are formed: a) Allantois b) Chorion c) Amnion III. Fertilization and Copulation Copulatory organs: Turtles and crocodilians: a penis of spongy connective tissue erects and retracts via vascular pressure Squamates: penis lost and later replaced by hemipenes III. Fertilization and Copulation A B C D Photographs of hemipenis in snakes III. Fertilization and Copulation Sperm Storage: Delayed fertilization permits females to mate with more than one male and can result in multiple paternity In reptiles it is not as common as in amphibians Sperm storage tubules are located on the upper mid section of oviducts Mechanism for expelling sperm from these tubules is unknown IV. Reproduction Without Fertilization Asexual Reproduction One type in reptiles: Parthenogenesis Occurs when females reproduce without the involvement of males or sperm Inheritance is clonal Genetic variation within an individual is high, but among individuals is almost non-existent Premeiotic mitosis (doubling of chromosomes)  tetraploid oogonium  normal meiosis produces diploid gamete IV . Reproduction Without Fertilization Schematic representation of parthenogenesis in reptiles. Lizards belonging to the genus Lacerta are parthenogenic. V. Parental Care Three major types: a) Pre-depositional b) Post-depositional c) Live-bearing V. Parental Care Live-bearing: Two major types: a) Ovovivipary b) Vivipary V. Parental Care Ovovivipary: Involves the retention of eggs for much longer periods of time compared to oviparous species Embryos can be supported entirely by egg yolk Embryos also absorb some nutrients through the oviduct  Vivipary: Transfer of nutrient to developing embryo is through a placenta-like structure VI. Embryo Development Development is direct in all reptiles (not two “lives”) Clutch and egg size may be proportional to body size Reptilians that develop from terrestrial eggs: Humidity Temperature VI. Embryo Development Temperature-dependent Sex Determination (TSD) Widespread in reptiles Average temperature during 2nd trimester of development, and not sex chromosomes regulates gonad differentiation Crocs and lizards: ♂’s at high temp Turtles: ♂’s at low temperatures Reason? VI. Embryo Development Read-eared Slider Turtle (Trachemys scripta) VII. Growth Two growth pulses VIII. Age Absolute age is not as important as time required to reach major life history events: Reproductive periodicity is also very important Longevity can be great in some reptiles VIII. Age FNR 251 01/29/2007 IX. Dynamics of Reproduction Most reptiles exhibit seasonal patterns Turtles: gametogenesis is annual but asynchronous ♂’s ♀’s Crocodylians: cyclic annual breeders with synchronous gametogenesis Squamates: variety of patterns IX. Dynamics of Reproduction 1. 5. 2. 6. 3. 4. IX. Dynamics of Reproduction Mate attraction and selection Summary of Development in Amphibians and Reptiles Amphibians Reptiles Ovum Size 1 - 10 mm 6 – 100+ mm Review of Terms: Lecture 8  Gametogenesis and Ovulation: Allantois, Amnion, Corpora Lutea, Chorion, Cleidoic Egg, Ovulation, Pinocytosis, Vitellogenesis, Vitellogenin  Fertilization and Copulation: Copulatory Organs, Fertilization, Hemipenis  Reproduction without Fertilization: Asexual Reproduction, Parthenogenesis  Parental Care: Live-bearing, Vivipary, Ovovivipary, Post- depositional Parental Care, Pre-depositional Parental Care  Embryo Development: Temperature-dependant Sex Determination (TSD) LECTURE 9: GENETICS, REGIONAL VARIATION, AND BIOGEOGRAPHY I. Introduction Each population will adapt differently and will eventually diverge genetically (evolve) from other populations If this divergence continued, speciation would occur However, speciation is a rare outcome The rate of gene flow is a function of the closeness of the populations and the dispersal tendency of the species II. Classification Species : Today distinguished by differences in: Body function Biochemistry Behavior Genetic makeup Classical Biological Concept Definition: genetically distinctive populations of individuals isolated reproductively from FNR 251 02/05/2007tions II. Classification Alternative species concepts : Ecological species: defined in terms of its ecological niche Morphological species: defined by morphology (structure) Genealogical species: defined as a set of organisms with a common and unique genetic history as shown by molecular patterns II. Classification Subspecies : Def. 1: Taxonomic subdivision of a species Def. 2: A population of a particular region genetically distinguishable from other such populations and capable of interbreeding with them Def. 3: A grouping of organisms that differ from other members of their species by color, size or various morphological features II. Classification Prairie Racerunner Six-lined Racerunner (Aspidoscelis sexlineatus viridis(Aspidoscelis sexlineatus sexlineatus) II. Classification Cline : Gradual and continual change in a character by a series of populations or throughout the range of a species Usually along a line of geographic or environmental gradient, in which individuals at the two extremes differ markedly II. Classification Group of Populations Yellow Lines Each color: Zone of Clinal variation in Hybridization a species or Group of species II. Clinal Variation in Painted Turtles Plastral markings  Western forms –intricate  Hybrid – intermediate  Midwestern - single II. Classification How do you define a species when individuals do not interbreed? The case of the “ring species” Geographic Distribution and Clinal variation among the subspecies of Lungless Salamader: Ensatina eschscholtzi FNR 251 02/05/2007 III. Morphological Variation Latitudinal Changes Within a Species: a) Changes in Body Weight: Bergman’s Rule Animals have a tendency to be larger in polar regions, medium in temperate climates, and smallest in tropical ones Does not always apply to reptiles and amphibians b) Changes in body color IV. Biogeography Three major factors influence geographic distribution of amphibians and reptiles: a) Climate b) Availability and access to resources c) Dispersal abilities VI. Biogeography Amphibian Species VI. Biogeography Reptile Species Review of Terms: Lecture 9 Biogeography Clinal Variation Cline Intergradation Species Subspecies “Ring Species” LECTURE 10: MOVEMENTS, HOME RANGE, TERRITORY, AND HABITAT SELECTION I. Movements A. Locomotion: Amphibians : Reptiles: a) ________ ________ b) ________ ________ c) ________ ________ d) ________ ________ I. Movements I. Movements Locomotion in Snakes - crawl I. Movements Daily Movements: Main purposes are: a) Feeding b) Thermoregulation c) Predator avoidance I. Movements Seasonal Movements: Generally more extensive but still generally considered to be < 0.5 km a) Breeding b) Hibernation c) Habitat Utilization I. Movements Dispersal Movement outward from home area, often implies colonization Undirected movement to locations unknown by the dispersing animals Costs and Benefits I. Movements Orientation and Navigation: a) Piloting b) Compass Orientation c) True Navigation d) Others I.Movements Movements of Green Sea Turtles I. Movements Visual Cuesve Orientationagnetic Orientation Orientation in Baby Loggerhead Turtles (Chelonia mydas) I. Movements Experiments that Demonstrated that Sea Turtles can Orient Using Wave Movements I. Movements Experiments that Demonstrated that Sea Turtles Can Detect Magnetic Fields II. Home Range II. Home Range 2 Home Range (m Seasonal Variation in Home Range for Male II. Home Range Defense (territoriality): usually very expensive, but where a required resource is insufficient for all individuals, defense may have evolutionary advantage Types: a) Territorial defense b) Site defense c) Non-defense Review of Terms: Lecture 10 Movements: Compass Orientation, Daily & Seasonal Movements, Dispersal, Habitat Utilization, Hibernation, Hibernacula, Locomotion (different types), Piloting, True Navigation Home Range: Defense (territoriality), Non- defense, Site Defense, Territorial Defense LECTURE 11: FEEDING AND FOOD HABITS I. Introduction Although some exceptions exist, amphibians and reptiles mostly feed on: Caecilians: invertebrates (earthworms) Frogs and Salamanders: insects Crocodylians: vertebrates Turtles: plants and animals (vertebrates and invertebrates) Squamates: animals (invertebrates and vertebrates) II. Projectile T ongues Projectile Tongue in Amphibians projectile tongue (Rhinella marinus) II. Projectile T ongues Tongues in Plethodontidae Salamanders II. Projectile Tongues Mechanism of Tongue Projection in Chameleons See Deban lab videos!! FNR 251 02/09/2007 II. Digestive System Digestive Glands a) Oral cavity Amphibians: Intermaxillary gland Reptiles: venom glands b) Stomach and intestines FNR 251 02/09/2007creas II. Digestive System • Opisthoglyph II. Digestive System Proteroglyph elapid snakes Common Cobra Naja naja II. Digestive System Venom Gland Fang Solenoglyph Viperid Snakes III. Foraging Modes Two general foraging modes: a) Sit-and-wait (or “ambush foraging”) b) Active Foraging (or “wide foraging”) There is likely a continuum of foraging modes from these two extremes III. Foraging Modes Character Sit-and-wait Active Escape behavior Crypsis, venoms Flight, skin or blood toxins, venoms Foraging behavior: Movement rate Low High Prey types Mobile Sedentary Sensory Mode Vision Vision and olfactory Physiological characteristics: Endurance Limited High Sprint speed High Intermediate to low Heart mass Small Large Active body temperature Moderate (25 -37°C) High (32-41°C) Energetics: Daily energy expenditure and energLow High intake Social behavior: Home range size Small Large Territoriality Common Rare III. Foraging Modes Factors influencing foraging behavior: a) External factors b) Internal factors c) Phylogenetic factors II. Prey Detection Amphibians and reptiles can detect prey using different cues: a) Visual b) Chemical c) Tactile d) Thermal II. Prey Detection In general: Caecilians: chemical Salamanders and Frogs: visual and chemical (olfactory) Crocodylians: tactile and chemical Turtles: visual Squamates: entire spectrum of cues II. Prey Detection 1. Visual Prey Detection: Mostly used by sit-and-wait predators Large, well-developed eyes Discriminate prey based on shape and size mostly Binocular perception Most align their heads or entire body axis with that of prey before attacking II. Prey Detection 2. Chemosensory Prey Detection: a) Olfaction b) Vomerolfaction (Jacobson’s organ) c) Taste II. Prey Detection Jacobson’s Organ II. Prey Detection 3. Tactile Prey Detection: Mechanoreceptors in the skin (example: lateral line in aquatic amphibians) In several species, flaps of skin are highly innervated and also help in the tactile detection of prey II. Prey Detection 4. Thermal Prey Detection: Infrared light is sensed by nerve endings in the skin of the head which are located inside pit organs Pits open anteriorly (always face forward) and provide a binocular perception field Most effective for nocturnal species that feed on mammals and birds II. Prey Detection Pit Organs III. Prey Capture and Ingestion Prey Capture: a) Biting and Grasping b) Constriction c) Injected venoms III. Prey Capture and Ingestion Prey Capture: d) Filter Feeding e) Suction Feeding f) Projectile Tongues III. Prey Capture and Ingestion  Prey Ingestion:  Most amphibians and reptiles swallow prey (in most case still alive) whole immediately after capture  Large reptiles (crocodiles), on the other hand, can hold prey in mouth for several days until it begins to decompose  Two main swallowing mechanisms: a) Inertial feeding b) Manipulation of tongue and hyoid IV. Food Habits Specific food habits depend on: a) Feeding adaptations of animal b) Size of animal and prey-capturing methods c) Habitat d) Relative abundance and size of prey available at time of feeding Review of Terms: Lecture 11  Digestive System: Gastrointestinal Tract (mouth, oral cavity, pharynx, esophagus, stomach, intestines, cloaca), Tongue (retractable, telescopic), Digestive glands (maxillary)  Foraging Modes: Sit-and-wait vs. Active  Prey Detection: Binocular perception, Chemosensory Prey Detection, Olfaction, Tactil Prey Detection, Taste, Thermal Prey Detection, Visual Prey Detection, Vomerolfaction  Capture and Ingestion: Biting and Grasping, Fangs, Prey Capture & Ingestion, Salivary & Venom Glands  Food Habits: Carnivory, Herbivory, Omnivory LECTURE 12: SOCIAL SYSTEMS, COMMUNICATION AND BEHAVIORS I. Introduction Concepts to be covered in this lecture: Communication Social systems and group behaviors II. Communication: Types Definition Four basic types of communication: a) Visual b) Acoustic c) Chemical d) Tactile II. Communication: Caecilians Chemical Cues: Have a specialized chemosensory organ: the tentacles Paired structures located anterior to the eyes and lumen of each connects to Jacobson’s organ II. Communication: Salamanders Chemical Cues: Salamanders use pherohormones These hormones are produced by courtship glands Tactile Cues: Mate location in Plethodontid salamanders is aided by nose-tapping Also bite, slap or rub part of their bodies against each other II. Communication: Salamanders Male Plethodon jordani Slapping his Courtship Gland on the Snout of the Female During Courtship FNR 251 02/14/2007ds of Plethodontid Salamanders II. Communication: Salamanders Courtship sequence in the Mole Salamander (Ambystoma talpoideum) FNR 251 02/14/2007 II. Communication: Salamanders Tail Straddling Walk During Courtship of a Plethodontid Salamander (Plethodon jordani) FNR 251 02/14/2007 II. Communication: Frogs Acoustic Cues: very important Four basic categories of calls: Advertisement Reciprocation Release Distress Frogs produce sound by passing air over their vocal cords found in vocal sacs II. Communication: Frogs Larynx Lung Vocal Sound Sac Sound Production of the Marine Toad (Bufo marinus) II. Communication: Frogs Visual Cues: Bright colorations Mostly in diurnal species II. Communication: Frogs Golden Frog (Brachycephalus ephippium) Harlequin Poison Arrow Frog Poison Arrow Frogs (Dendrobates histrionicus) FN(Dendrobates azureus) II. Communication: Turtles Visual Cues: Headbobs, Ram, Flip, Trailing, Biting (♂:♀  courtship and copulation; or ♂:♂ aggressive encounters) Encounters in Emydid turtles: Patterns and colors of limbs, shell, head Chemical Cues: Special glands on the bridge of their shells Cloacal secretions may also play a role II. Communication: T urtles Sequence of Behaviors During an Aggressive Encounter Between two Male Desert Tortoises (Gopherus agassizii) II. Communication: T urtles __________________ by a Tortoise (Gopherus polyphemtus) II. Communication: Crocodylians Visual Cues: Several stereotyped complex displays: e.g. “Head emergent-tail arched”, “inflated”, and “head-slaps” postures in ♂:♂ aggressive encounters Auditory Cues: Bellowing and “coughing” (adults); grunts (juveniles), and slapping sounds II. Communication: Crocodylians Head-slap Display (35”) Bellowing Display (5”) Visual and Acoustic Displays of the American Alligator FNR 251 02/14/2007 (Alligator mississippiensis) II. Communication: Lizards Visual Cues: Coloration of dewlaps, heads and sides of the body in males and bright coloration in females Chemical Cues: Pherohormones Tactile Cues: Tongue flicking Neck and body scratching II. Communication: Lizards SIMPLE DISPLAYS FNR 251 02Visual Displays in Anolis lizards II. Communication: Lizards COMPOUND DISPLAYS FNR 251 02Visual Displays in Anolis lizards II. Communication: Lizards COMPLEX DISPLAYS FNR 251 02Visual Displays in Anolis lizards II. Communication: Lizards Brown Anole (Anolis sagrei) Green anole (Anolis carolinensis) FNR 251 02/14Visual Displays in Anolis lizards II. Communication: Snakes Chemical Cues: Pherohormones are produced both by the skin (mating and courtship) and cloaca (defense and trailing) Tactile Cues: Courtship and mating Male combat II. Communication: Snakes Tactile Signals Used by Snakes During Courtship and Mating FNR 251 02/14/2007 III. Group Behavior: Competition Competition: 1. Interspecific: occasionally occurs among related species; frequently congregating species partition habitat temporally (especially during breeding) 2. Intraspecific: occasionally occurs when resources are limited; minimized in larval/juvenile forms III. Group Behavior: Cooperation Cooperation: Protocooperation better term for amphibians and reptiles Three forms of protocooperation: a) Crowding b) Hibernation c) Breeding Aggregations III. Group Behavior: Kinship Definition of Kinship: traits (behaviors) that do not benefit an individual’s survival and potential for reproductive success but do benefit survival and reproduction of kin III. Group Behavior: Kinship Rana cascadae (Cascades frog) tadpoles associate with familiar half-sibs and non-sibs; occur in cohesive aggregations Rana aurora (red-legged frog) recognize siblings if raised with them but not if raised away from them Rana pretiosa (spotted frog) lack ability to recognize kin at all Review of Terms: Lecture 12 Communication: Visual, Acoustic, Chemical, and Tactile Cues; Calls (advertisement, reciprocation, release, distress); Courtship glands; Nose-tapping; Pherohormones; Social behavior; Tentacle; Vocal sacs. Group Behavior: Competition (intra and interspecific); Cooperation; Kinship; Protocooperation (crowding, hibernation, breeding aggregations). Amphibian & Reptile Diseases Emerging Infectious diseases • Pathogens may be newly introduced to an area where populations have no previous exposure or immune response – Zoonose = infectious disease that can be transmitted between species (usually wild animals & humans) – Introduced species: vectors/reservoirs for disease organisms Categories of Infectious agents • Pathogens: –Bacterial –Fungal –Viral –Parasitic (Metazoan, trematode)s Bacterial: Salmonella • Many reptiles & amphibians are likely carriers or susceptible – Reptiles more prevalent – Most significant zoonotic pathogen of reptiles • Handling or ingestion • Higher carrier rate in captive reptiles Bacterial: Salmonella • Pet turtles • Up to 90% reptiles carry strains in GI tract – Bacteria shed in feces • Salmonellosis = bacterial infection in humans • More serious in children Water Mold • Saprolegnia sp. • Widespread, common worldwide • Oomycete (egg fungi) = Secondary superficial infections in fish and amphibians • Greatest impact on egg masses – Significant mortality – Appears as “white fuzz” under microscope Water Mold • Saprolegniasis: potentially lethal infection with fungus • Some herps: – Bufonids – Ranids – Hylids – Ambystomids – Cryptobranchids Chytrid • Chytrid, Batrachochytrium dendrobatidis, “Bd” • Fungus attacks keratinized tissue – in skin of adults – Mouthparts of tadpoles (oral disc) • Chytridiomycosis: fatal disease caused by the fungus • Appears to have low host specificity – Chytrid fungus: 94 of 120 species of frog species extinct since 1980 Chytridiomycosis • Skin becomes thick (hyperplasia, hyperkeratosis) • Interferes with absorption/osmoregulation of water, oxygen, sodium & potassium, electrolytes • Individuals suffocate, or abnormal electrolyte levels – can cause heart to stop beating Life Cycle Chytrid Distribution The Ecology of Chytrid • Lips 2006: Bd can likely spread in mist/clouds • Persist for several months • Not restricted to local water contact • 100 km/yr Bd • Captive treatment: – Itraconazole bath – Elevate body temperature • Wild: Some individuals remain, “persist” in populations following some mass mortality events • Persistent populations could bounce back over time • Wild?... Treat small percentage of individuals: reduce intensity of infection, Symbiotic Bacteria, & Peptide secretion treatment Chytrid • Can persist on mud on boots, nets • Disinfect Low 1-3 % bleach solution • Dry for 3 hrs kills chytrid • Use gloves when sampling individuals Malformations • Increasing number of reports of malformed frogs in other locations – 44 states representing 60 species • Are malformations a significant factor contributing to population declines? Examples of malformations • Polymelia • Polyphalangy • Brachydactyly arch/amph_dc/frog.pdf Purported Causes of Malformations • Chemical contamination • Exposure to UV light • Parasites? – Ribeiroia sp. Malformation in Salamanders Adult Malformations Ectrodactyly Polyphalangy Brachydactyly Polymelia Larval Malformations Larval Malformations Larval Malformations Ranaviruses • Family: Iridoviridae • Ranavirus sp. (6 species) • Double stranded DNA virus • Every Continent • More Recent “Emerging” disease Ranavirus • Dieoffs: – 25 states – 20 amphibian species – 2 chelonian species Ranavirus • Viral infections common at high densities • Mortality highest in larvae approaching metamorphosis • Ranavirus can eliminate local populations Ranavirus • Disease transmission – Direct contact – Necrophagy – Indirectly via water & fomites – Other vectors? • Sublethal effects: some individual metamorphs may carry to other ponds? Ranavirus • Human assisted transport – Salamander bai


Buy Material

Are you sure you want to buy this material for

50 Karma

Buy Material

BOOM! Enjoy Your Free Notes!

We've added these Notes to your profile, click here to view them now.


You're already Subscribed!

Looks like you've already subscribed to StudySoup, you won't need to purchase another subscription to get this material. To access this material simply click 'View Full Document'

Why people love StudySoup

Steve Martinelli UC Los Angeles

"There's no way I would have passed my Organic Chemistry class this semester without the notes and study guides I got from StudySoup."

Anthony Lee UC Santa Barbara

"I bought an awesome study guide, which helped me get an A in my Math 34B class this quarter!"

Jim McGreen Ohio University

"Knowing I can count on the Elite Notetaker in my class allows me to focus on what the professor is saying instead of just scribbling notes the whole time and falling behind."

Parker Thompson 500 Startups

"It's a great way for students to improve their educational experience and it seemed like a product that everybody wants, so all the people participating are winning."

Become an Elite Notetaker and start selling your notes online!

Refund Policy


All subscriptions to StudySoup are paid in full at the time of subscribing. To change your credit card information or to cancel your subscription, go to "Edit Settings". All credit card information will be available there. If you should decide to cancel your subscription, it will continue to be valid until the next payment period, as all payments for the current period were made in advance. For special circumstances, please email


StudySoup has more than 1 million course-specific study resources to help students study smarter. If you’re having trouble finding what you’re looking for, our customer support team can help you find what you need! Feel free to contact them here:

Recurring Subscriptions: If you have canceled your recurring subscription on the day of renewal and have not downloaded any documents, you may request a refund by submitting an email to

Satisfaction Guarantee: If you’re not satisfied with your subscription, you can contact us for further help. Contact must be made within 3 business days of your subscription purchase and your refund request will be subject for review.

Please Note: Refunds can never be provided more than 30 days after the initial purchase date regardless of your activity on the site.