Der Frosch

download report

Transcript Der Frosch

locomotion by jumping
great
importance in
the ecologic
system
The frog
•
short and compact body, big eyes
sidewise, long hind legs
lives everywhere,
except at Antarctica
Table of contents
• Progression
• Catching prey
• In winter and summer
• Enemies
• Locomotion
Progression of the frog
(Metamorphosis)
spawn of frogs
- about 2500 eggs in a cluster
- each egg is situated in a (gelatinous) wrapping
- this wrapping protects and provides food at the
beginning
tadpole
- hatch out after 10 days
- about 6mm long
- breathing by gill-tufts
- helmtail for locomotion
gill-tuft
helmtail
tadpoles with legs at the front and the back
- about 4 weeks old
- gill-tufts degenerate
- inner gills appear
- first hind legs grow, then forelegs
- helmtail degenerates
- food: algae and water plants
completely developed frogs
- leaves water after 12 weeks of evolution
- breathing through airbags
- food: insects, amphibians, small fish
- length: 5-10 cm
- Goliathfrogs up to 60 cm long and 4 kg
How to spend the winter:
- in mud
- in soil
- in abandoned
constructions
of other animals
frogs are hematocryal
How to spend the
summer:
- in sand or clay
(e.g. Australia)
Locomotion
nearly no neck
no tail
foreleg small
and stron
flashs
hind leg long, muskulös
sceletton is build in a manner to provide good swimming and jumping skills
Catch of prey
- sticky tounge is fastened at the front of the jaw
- when spotting a prey it opens ist mouth
- tongue unrolls and comes out relatively uncontrolled
It has no teeth!
Enemies
cars
mammals
snakes
storks
water birds