Amphibians Feeding Adaptations & Sensory Systems Flashcards
What are the two tyes of aquatic species feeding
Suction Feeding and Suspension
Expansion of the buccam cavaity to create negative pressure
Suction Feeding (latval paedomorphic salamanders)
Water is drawn into the mouth by creating negative pressure, large particples go straight to esophagus, small partciles are passed to branchial arches
Suspension Feeding (most tadpoles)
Labial teeth
Most tadpoles have these letstinized structures on their oral discs that help them eat
How do the tadpoles of spadefoot toads exhibit plasticity?
- At hatching, all have an omnivore morphology
- Depending on environment, the tadpoles develop into either omnivores or carnivores
- Carnivores arise facultatively through ingestion of large shrimp and tadpoles can change back to the alternative morphology if their diet is switched
What species faces cannibalism?
Spadefoot toads and tiger salamanders
How does the cannibalistic morph look in comparison to the typical morph?
Cannibal has enlarged head and vomerine ridge (teeth) with assist them when feeding on conspecifics. They have increased growth rate and acclerated metamorphosis, but this morph can be reversed it conditions change withina certain critical period.
What are the two feeding types in terrestrial amphibians species?
Non projectile and projectile feeding
The body moves forward and bites down on prey
Nonprojectile feeding (seen in some frogs, salamanders, and all caecilians)
Sticky tongue shoots out and quickly grom the mouth capturing prey
Projectile feeding (most common form of feeding in salamanders and frogs)
Hyobranchial apparatus
Structural base for the tongue, attacjed to lower jaw/skull/perctoral girdle and functions for ventilation and feeding for terrestrial salamanders and frogs
What species has the protusible tongue attached anteriorly?
Ambystoma maculatum
What is buccal pumping and what species does it?
Breathing with the cheeks (the hypbranchial apparatus is used for this); Ambystoma maculatum
What suborder of amphibians have no lungs?
Salmandrina (& Plethodontidae)
Is capture if prey with tongue homology or homoplasy?
What is the lingual flip and is it projectile or nonprojectile feeding?
Tongue is flipped out like a catapult rather than being shot out using the hypbranchial apparatus; Tongue is commonly attached to the front of tje mouth and is flipped out (back side grabs prey)
Why frogs close their eyes when eating/swallowing?
Swallowing behaviors involve movements of the head, hyobranchial apparatus, jaws, tongue, and eyes. They used their eyes to push down food while swallowing
What is the amphibian sensory organ?
Vomeronasal organ (Jacobson’s organ) which is a sac in the roof of the mouth which has specialized sensory cells for detecting volatile and non volatile molecules in the air
Nasolabial Grooves
Nose sensory organs that run from the nostrils fown the front of the face
How do plethodontid Salamanders use their nose for chemoreception and reproduction?
Press the front of the nose against the ground, causing fluid to be drawn into the groves and transferred up to the nostrils by capillary action and into the vomeronasal organ
What sensory system do frogs (like Agalychnis callidryas) use?
Vibration
What species have protrusible tentacles and what is it used for?
Caecilians ; we think that they are used for chemoreception but theyre not well understood
In tetrapods, how do thwy adjust their vision?
They use the muscles in the eyes to change the shape (curvature of the lens to focus) and they have a thicker cornea
What is the nictitating membrane in amphibians?
A secondary, transparent/semi membrane that covers the eye and helps to keep it moist
What species are nearly blind?
Subterranean & cabe dwelling salamanders and caecillians
Do all tetrapods have an inner ear? Explain.
Yes but the organization is different in amphibians, reptiles/birds, mammals. They evolved indepently in each lineage.
Tympanum/tympanic membrane
External ear drum
Columella
Single bone that transmits sound to modified hair cells in the inner ear
Lateral line
Retained in larval stages and fully aquatic amphibians; detects movement and vibration in water
How does the adult vs larvae different in Amphibian Diet
Adults are mostly carnivorous and larvae are often herbivorous
