Amphibian Phylogeny

Lungfish First discovered 1830 First discovered 1830 Lungs similar to land animals Lungs similar to land animals Modified swim bladder Modified swim bladder They are closest relative of tetrapods (4 legs) They are closest relative of tetrapods (4 legs) Tooth enamel Tooth enamel Similar skull bone structure Similar skull bone structure Pulmonary and systemic circuit of blood flow Pulmonary and systemic circuit of blood flow Four similar sized limbs Four similar sized limbs

Lungfish

Coelacanth atomy-coelacanth.html atomy-coelacanth.html atomy-coelacanth.html atomy-coelacanth.html Type of lobed-finned fish Type of lobed-finned fish

Origins of Amphibians

Metamorphosis Metamorphosis

Apoda: Worm like

Urodela: Newt/Salamander Michigan Species Michigan Species Blue-spotted Salamander Blue-spotted Salamander Eastern Newt Eastern Newt Eastern tiger salamander Eastern tiger salamander Four-toed salamander Four-toed salamander Marbled salamander Marbled salamander Mudpuppy Mudpuppy Red-backed salamander Red-backed salamander Small mouthed salamander Small mouthed salamander Western lesser siren Western lesser siren

Examples of Michigan Urodela Blue-spottedEastern Newt4-toed Blue-spottedEastern Newt4-toed Marbled Marbled

Anura Michigan Species Michigan Species Blanchard’s cricket frog Blanchard’s cricket frog Bullfrog Bullfrog Eastern American toad Eastern American toad Fowler’s Toad Fowler’s Toad Grey tree frog Grey tree frog Green frog Green frog Mink frog Mink frog N. leopard frog N. leopard frog N. spring peeper N. spring peeper Pickerel frog Pickerel frog W. chorus frog W. chorus frog Wood Frog Wood Frog

Michigan species Bullfrog greenfrogleopardPickerel Bullfrog greenfrogleopardPickerel WoodSpring peeper WoodSpring peeper

Salamanders Tailed amphibian Tailed amphibian American Hellbender American Hellbender  Must live in moist areas Must live in moist areas Secrete mucus Secrete mucus Maintain moisture Maintain moisture Balance salt levels Balance salt levels Protection Protection

Salamanders vs. Lizards: Salamanders vs. Lizards: SalamandersLizards Skin Similar to Ours Covered in Scales ClawsNoYes Postur e Body low to the ground Body held higher above the ground Life Cycle Start as Larvae Start as smaller adults

General Anatomy

Salamander Respiration Types of Respiration: Types of Respiration: External gills External gills Mudpuppy Mudpuppy Lungs Lungs Single simple lung Single simple lung Very inefficient Very inefficient Skin (cutaneous respiration), all salamanders can do this Skin (cutaneous respiration), all salamanders can do this Why they must remain moist Why they must remain moist

Aquatic Habitat Larvae are born in water using external gills Larvae are born in water using external gills Juveniles and Adults breathe through external gills if retained, skin if not Juveniles and Adults breathe through external gills if retained, skin if not Breathing through skin requires constant moisture, easy if aquatic Breathing through skin requires constant moisture, easy if aquatic EX: Mudpuppy EX: Mudpuppy

Environmental Issues Salamanders, like all amphibians are one of the first organisms to be affected by environmental changes due to their soft-shelled eggs and respiring skin. Salamanders, like all amphibians are one of the first organisms to be affected by environmental changes due to their soft-shelled eggs and respiring skin. Aquatic eggs are jelly-like and can be affected by UV and chemicals in the water. Aquatic eggs are jelly-like and can be affected by UV and chemicals in the water. All salamanders can breathe through their skin so any chemicals that come in contact with them easily pass into their bodies. All salamanders can breathe through their skin so any chemicals that come in contact with them easily pass into their bodies. Moisture is critical to all salamanders. Moisture is critical to all salamanders. Deforestation leads to areas with less moisture, effectively destroying terrestrial salamander habitat Deforestation leads to areas with less moisture, effectively destroying terrestrial salamander habitat

Anura (Frog/Toad) Live everywhere (except Antarctica) Live everywhere (except Antarctica) Most species in tropics Most species in tropics Ectotherms Ectotherms Evolved capabilities to live in all biomes Evolved capabilities to live in all biomes Desert, mountain, tropics, freshwater systems Desert, mountain, tropics, freshwater systems

Toads Rough, dry skin Rough, dry skin Very terrestrial Very terrestrial Use soil to maintain body moisture Use soil to maintain body moisture Need water source for larva stage (tadpole) Need water source for larva stage (tadpole)

Toads

Frogs Smaller body structure than toad Smaller body structure than toad More angular than toad body More angular than toad body More reliant on water than toads More reliant on water than toads Moist skin Moist skin Secrete mucus Secrete mucus Similar to function in salamanders Similar to function in salamanders

General Frog/Toad Anatomy

Anterior Anatomy Key Features Key Features Nicitating membrane Nicitating membrane 3 rd eyelid 3 rd eyelid Tympanic membrane Tympanic membrane External eardrum External eardrum Eustachian Tubes Eustachian Tubes Balance pressure Balance pressure Teeth Teeth 2 vomerine teeth: 2 vomerine teeth: Maxillary teeth: hold prey Maxillary teeth: hold prey

Anterior Anatomy

Skeletal System Similar to mammalian skeleton Similar to mammalian skeleton Functions as system of levers Functions as system of levers Muscle attachment Muscle attachment

Digestive Very similar to other vertebrates Very similar to other vertebrates Digestive Tract: What nutrients pass through Digestive Tract: What nutrients pass through Mouth  Esophogus  Stomach  Small Intestine (duodenum, ileum)  Large Intestine/Colon  Cloaca  Vent Mouth  Esophogus  Stomach  Small Intestine (duodenum, ileum)  Large Intestine/Colon  Cloaca  Vent Accessory Organs: Provide enzymes Accessory Organs: Provide enzymes Liver/gall bladder Liver/gall bladder Gastric gland Gastric gland Pancreas Pancreas

Excretory System Use skin to excrete some waste (respiratory waste) Use skin to excrete some waste (respiratory waste) Cloaca collects digestive waste Cloaca collects digestive waste Kidney major excretory organ Kidney major excretory organ Urinary system Urinary system

Circulatory System Pulmonary and systemic circulation Pulmonary and systemic circulation Pulmonary: Heart  Lung  Heart Pulmonary: Heart  Lung  Heart Systemic: Heart  Body  Heart Systemic: Heart  Body  Heart Atrium(s) Atrium(s) Left: collects blood from lung, sends to the ventricle Left: collects blood from lung, sends to the ventricle Right: Collects blood from body, sends to ventricle Right: Collects blood from body, sends to ventricle Ventricle Ventricle Pumps blood to both lungs and body Pumps blood to both lungs and body

Major Vessels Conus arteriosus: Heart  systemic or pulmonary circ. Conus arteriosus: Heart  systemic or pulmonary circ. Pulmonary vein: Lung  Heart (LA) Pulmonary vein: Lung  Heart (LA) Pulmonary artery: Conus arteriosus  lung Pulmonary artery: Conus arteriosus  lung Sinus Venosus: Body  Heart Sinus Venosus: Body  Heart

Problems w/ 3 chambered Heart Not as efficient as a 4 chambered (mammalian heart) Not as efficient as a 4 chambered (mammalian heart) Oxygenated and deoxygenated blood mix Oxygenated and deoxygenated blood mix Lungs get some blood that is already oxygenated Lungs get some blood that is already oxygenated Body gets some blood that is already deoxygenated Body gets some blood that is already deoxygenated

Respiration Use both lung and skin to exchange gases Use both lung and skin to exchange gases Skin = pulmocutaneous circulation Skin = pulmocutaneous circulation 4 options for respiration 4 options for respiration May use one or more May use one or more Lungs (adult) Lungs (adult) Skin (adult) Skin (adult) Mouth (adult) Mouth (adult) Gill (larva, some adults-mudpuppy) Gill (larva, some adults-mudpuppy)

Nervous Similar to that of a fish Similar to that of a fish

Reproductive Do not have amniotic egg Do not have amniotic egg No water barrier  must keep moist No water barrier  must keep moist Most use external fertilization Most use external fertilization Male fertilizes eggs as female lays them Male fertilizes eggs as female lays them