Presentation on theme: "Frogs and Toads. Toads Toads have dry, warty skin Generally found in drier climates Stubby bodies with short hind legs Parotid (poison) glands behind."— Presentation transcript:
Frogs and Toads
Toads Toads have dry, warty skin Generally found in drier climates Stubby bodies with short hind legs Parotid (poison) glands behind the eyes Lay eggs in chains
Pelobatidae and Scaphiopodidae Spadefoot toads Burrowing toads Hardened protrusion on their foot for digging Very quick metamorphic stage – 2 weeks! Tadpoles are cannibalistic to speed up metamorphosis Native to Europe, W. Asia, and N. Africa
Bombinatoridae - Fire-bellied toads Brightly colored ventral sides – highly toxic to predators!! Aquatic toads Unken reflex - the animal will arch its back and limbs to expose the bright belly Lay pigmented eggs in ponds Native to northeastern asia
Bufonidae - The TRUE Toads All members of their family possess toad-like characteristics Occur on every continent except Australia and Antartica Inhabit a variety of environments Male toads possess a Bidder’s organ – generally inactive, but become an active ovary!!
Frogs Two bulging eyes Strong, long, webbed hind feet designed for jumping and swimming Smooth and slimy skin Lay eggs in clusters
Ascaphus - The Tailed Frogs – Wait a minute…what?!!? Mostly aquatic Tail is an extension of the cloaca – only found in males Minimizes sperm loss in turbulent waters Use internal fertilization (other frogs and toads use external) Primitive frogs – greater number of vertebrae, lack the ability to vocalize, and possess free ribs Found in North America
Dendrobatidae - Poison Dart Frogs Arboreal and terrestrial Native to Central and South America Brightly colored bodies to exhibit toxicity to predators Used to tip darts Piggy-back tadpoles once they hatch Exhibit parental care
Medical Application Nerve toxins affecting the nervous system and heart activity Muscle relaxants, heart stimulants, and appetite supressants Skin may be 200 times more potent than morphine! One species has enough poison to kill ten men!
Centrolenidae – Really cool Glass Frogs Coloration primarily lime green The internal organs, including the heart, liver, and gastrointestinal tract are visible through this translucent skin
Hylidae – Tree Frog Live in a variety of habitats including semi- aquatic, terrestrial, and arboreal Pronounced forward eyes Adhesive pads on the toes and fingers Come in all different colors!!
Ranidae – The TRUE frogs The widest distribution of any frog family Occurs in all continents except Antarctica Large, powerful legs and extensive webbing on their feet Many are aquatic and most live close to the water Some are arboreal and burrowers Occur in all sizes – largest frog in the world is the Goliath frog
Why are frog species important? Frogs are keystone species. – A keystone species plays a critical role in maintaining the structure of an ecological community. – Because they are sensitive to changes in the environment, they may suffer from huge increases in mortality. Can help to determine the overall health of an ecosystem.
Why are frog species important? Invaluable tool for studying body systems. – Dissections on frogs can be used to compare to other vertebrates Important source of food – Frog legs – taste like chicken? Medicinal purposes – Poison dart frogs