Amphibians Class Amphibia

1
AmphibiansClass Amphibia
2
Amphibians

• Animals that can live on land and in water
• Chinese Giant Salamander

3
Amphibians

• First animals with four limbs
• Tetrapods vertebrates that have four limbs.

4
Acanthostega

• Found in 360 million year-old rocks in Greenland
• Had lungs and eight-toed legs, but also had gills
  and a lateral line system.

5
Fish to Amphibian Transition
6
Adaptationshelp amphibians live on land

• Large shoulder and hip bones help support more
  weight.

7
Adaptations

• Interlocking projections on the vertebrae help
  keep the backbone from twisting and sagging.

8
Adaptations

• Mobile, muscular tongue allows amphibians to
  capture and manipulate food.

9
Adaptations

• Development of a middle ear help some amphibians
  hear out of water.

10
Adaptations

• Breathe through the skin or with the use of gills
  or lungs

11
Adaptations

• Amphibians have a three-chambered heart

12
Amphibians return to the water to reproduce

• Eggs do not have shells

13
Strategies to keep eggs wet

• Laying eggs directly in water
• Laying eggs on moist ground
• Wrapping eggs in leaves
• Brooding eggs in pockets on the females back

14
Pygmy Marsupial FrogFlectonotus pygmaeus
15
(No Transcript)
16
Tadpoles

• Some frogs start as tadpoles
• Have gills and a broad-finned tail

17
Amphibian Metamorphosis

• Change in form and habits of an animal
• It affects nearly every organ in the tadpoles
  body

18
(No Transcript)
19
Tadpole into Adult Frog

• Gills are reabsorbed and lungs develop
• Circulatory system is reorganized to send blood
  to the lungs
• Tail fin is reabsorbed

20
Tadpole into Adult Frog

• Body grows limbs and completely reorganizes its
  skeleton, muscles, and parts of the nervous
  system.
• Digestive system is rebuilt to handle a
  carnivorous diet.

21
(No Transcript)
22
Three Groups of Modern Amphibians

• Salamanders
• Frogs
• Caecilians

23
Salamanders

• More than 300 species
• Long body
• Four walking limbs
• tail

24
Salamanders

• Walk with a side-to-side movement that may be
  similar to ancient tetrapods
• The largest family of salamanders do not have
  lungs, so they exchange gases through the lining
  of their skin and mouth.

25
Family Plethodontidae

• Lungless salamanders
• Most common kind

26
Salamanders

• Larvae and adults are carnivores
• Invertebrates Vertebrates
  Insects Fish
• Worms Frogs
• Snails

27
Frogs

• Over 3000 species
• Largest group of living amphibians

28
Adult Frogs

• Tailless bodies
• Long, muscular hind limbs
• Webbed feet
• Exposed eardrums
• Bulging eyes

29
Adult Frogs

• Bodies adapted for jumping
• Elongated bones in their hips, legs and feet for
  increased speed and power
• Hind legs have fused bones that absorb the shock
  of landing

30
Toads

• One family of frogs
• Rougher, bumpier skin
• Shorter legs- not good jumpers
• Glands make toxins that protect them from
  predators also in tropical frogs

31
Frogs

• Live in every environment on Earth except at the
  poles and the driest deserts.

32
Caecilians

• Legless, burrowing amphibians
• Live in the tropics, such as South America

33
Caecilians

• 160 species
• Range from 4 inches to 5 feet
• Banded bodies that make them look like giant
  earthworms

34
Caecilians

• Are predators
• Search for earthworms and grubs
• Have no arms or legs for burrowing, so have to
  move like an earthworm.
• Use hydrostatic skeleton to stiffen its body and
  drive its head forward like a battering ram.