Amphibians
What Is an Amphibian? •Live in wet places •Ectothermic •Carnivorous •Moist skin •Lay eggs in water •Most larvae have gills •3-chambered heart •Terrestrial adults respire through lungs and skin •Ex: salamanders, frogs, toads & caecilians
Evolution of Amphibians 1st amphibians resembled lobe-finned fishes with legs Appeared in the late Devonian Period, about 360 mya Amphibians were the first chordates to live at least part of their lives on land.
Amphibian Adaptations •Stronger bones in limbs, allowing more efficient movement. •Lungs & breathing tubes enabled amphibians to breathe air. •Developed sternum to support & protect internal organs.
Orders of Amphibians Urodela – salamanders & newts Apoda - caecilians
Orders of Amphibians Anura – frogs and toads
Anatomy of a Frog Circulatory system
Anatomy of a Frog Skeletal system
Anatomy of a Frog
Anatomy of a Frog
Anatomy of a Frog Nictitating membrane – a transparent membrane that protects the eye from damage under water and keeps it moist on land. Tympanic membrane - external eardrum that vibrates sending sound waves to the inner ear.
Amphibian Reproduction Reproduction in amphibians is external. The male will grip the female tightly and fertilizes eggs as they are laid.
Amphibian Reproduction