Frogs and Toads

1. Frogs and Toads

2. 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

3. Pelobatidae and ScaphiopodidaeSpadefoot 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

4. http://asm.wku.edu/froglogger/default.html

5. 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

7. 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!!

8. http://bioweb.wku.edu/froglogger/

9. Frogs • Two bulging eyes • Strong, long, webbed hind feet designed for jumping and swimming • Smooth and slimy skin • Lay eggs in clusters

10. 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

11. 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

12. 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!

13. 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

14. 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!!

15. http://bioweb.wku.edu/froglogger/

16. 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

17. http://asm.wku.edu/froglogger/default.html

19. 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.

20. 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