Amphibians/Reptiles Flashcards
What are the three different types of colour pigment cells?
- Melanophores: black, brown, reddish- gives dark pigmentation
- Iridophores: reflect light
- Xanthophores: yellow, orange and red
What two groups are in Urodela?
Salamanders and newts
What type of swimming form do urodela use?
Undulating
What is paedomorphosis and what group possesses this feature?
Where the adults retain their juvenile features
Urodela
Give an example of paedomorphosis
The retention of gills in the axolotl
How many species of Urodela are there?
400 species
What are cave dwellers called?
Troglodyty
What is the largest group of extant amphibians?
Anura
What two groups are within Anura and what does Anura mean?
Frogs and toads
An= without
Uro= tail
What features distinguish Anura?
Fast, powerful, hindlimb muscles
What group do caecilians belong to?
Gymnophiona
What are caecilians?
They’re legless and either burrowing or aquatic
Have dermal scales and internal fertilisation
Offspring eats their skin
What type of fertilisation is most common in amphibians?
External
Some use internal
What can parental care sometimes involve?
Attached to adults
Mouth or stomach brooders
Ovo-viparous
What can courtship involve?
Pheromones
Dimorphism
Advertisement calls
Strong sexual selection- usually females choice
What are the two character complexes that ensure reptiles aren’t dependent on aquatic habitats?
- Evolution of an egg with a shell impermeable to water but allows gas exchange
- A combination of traits that reduce water loss: skin is impermeable to water (apomorphine) and kidneys excrete concentrated urine (plesiomorphy)
What are the 4 extra embryonic membranes?
- Amnion: surrounds and protects the embryo itself
- Chorion: surrounds the embryo and yolk sac- gas exchange
- Yolk sac: membrane that contains all the nutrients needed for the embryo to develop
- Allantois: grows throughout development, stores nitrogenous waste
What are the two main groups of reptiles?
Synapsids: mammal like reptiles
Sauropsids: lizard like reptiles
What are the two groups within sauropsids?
Anapsids: includes testudines- primitive reptiles
Diapsids: archosaurs (dinosaurs, crocodiles, birds) and lepidosaurs (lizards and snakes)
What is the skull structure for anapsid, synapsid and diapsid?
Anapsid: no joke- turtles
Synapsids: single hole- mammals
Diapsids: two holes- dinosaurs, snakes, lizards, crocodiles and birds
