amphibians
Post on 19-Dec-2014
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Phylum Chordata!
Class amphibia
Class amphibia!
The amphibians– First vertebrates to inhabit
land
Still live part of life in water– Metamorphosis
Aprx. 5,000 species!Characteristics– Moist skin for gas exchange– Ectothermic– Larval stage
• metamorphosis
Movement from water to landWhat does it take to move from water to land? What has to change?
Small adaptations through Evolution
Transition from water to land
Living on land brings different challenges– Example: movement.
Amphibians are tetrapods: – “four footed: two sets of paired appendages that
are modified as legs that can support the animal.
Lungs to avoid drying out.
Adaptations = land living
New adaptations for living on land– Lungs – Ears – Four limbs with feet
and digits
CHARACTERISTICS
Ectothermic– Regulate
temperature from outside sources. • Basking in the sun • Water temperature
Vs. Endothermic
What would be the advantages of both?
Ectothermic: Advantages
Slow Metabolism– Eat less
Must self warm blood enough to be active
Not enough energy for continued hard work
CHARACTERISTICS
Respiration: Porous skin – Allow for gas exchange
(breathing)– Must live in moist
environments to avoid drying out
Sensitive to chemicals in the environment Salamanders do not have lungs and
must breath through skin
REPRODUCTIONInternal sexual reproductionLay 100s of eggs – Advantage of over population of offspring?
METAMORPHOSIS
Amphibian = double life
DIGESTION
Adults: carnivores– Use sticky tongue to
trap and suck in prey – Eat anything that is
small enough to swallow whole.
Does that make them active
predators or scavengers?
Larva: herbivores
SENSES
Great hearing and eye sight – Hearing is Important for
terrestrial living
Frogs can see color!
Other senses… – Chemical receptors on
skin– Taste buds on tongue– Nasal senses
ECOLOGICAL ROLE
Important prey for: – Racoons, opossums,
birds
Important predator of – Mice, rats, insects
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