Sensory Reception Flashcards
Chemoreception
Taste and olfaction
Taste Receptors
Mouth, head, gills, barbels, fins
NOT ON TONGUE
Olfaction
Nares on front of the head, paired pouch, incurrent and excurrent openings
Not connected to the mouth
High sensitivity to pheremones, food, etc – used for homing in salmon
Mechanoreception
inner ear (motion and sound detection)
Semicircular canals
Motion balance (fluid filled) – 3 canals
Ciliary attachment between otolith and canal wall
movement causes fluid to distort cilia
Otolith
Inner ear bone (aragonite)
Used to detect sound
Sagitta is the major bone used for sound reception and is highly variable between species
density similar to seawater
Rapid growth hatchery fish effects on otoliths
Wild fish have aragonite sp gr = 2.9
Hatchery fish replace aragonite with vaterite sp gr = 2.66
Asteriscus
This can be highly variable in Ostariophyseans
Otolith aging
They allow for the most precise aging of fish
Can see years spent in fresh and saltwater
Fish sound sensitivity
They are most sensitive to low frequency sounds
They use swim bladder to amplify high frequency sounds
Gas molecules in the air bladder vibrate and this amplifies the sounds
The closer the swim bladder is to the ear the better
Gadiform Swim Bladder Hearing
They have shifter the SB more anterior to detect cetaceans
Clupeiforms/Mormyrids Swim Bladder Hearing
The SB has shifted to enter the inner ear
Ostariophyseans Swim bladder hearing
The Weberian apparatus connects the SB to the skull
Sharks/Rays Hearing
They have no otoliths because they cannot produce bone
They have low sensitivity to sounds especially high frequency sounds
Sharks often use air/water interface as a “bladder” to amplify sound from below to detect it
Skates/rays use the sand grains they burry under to amplify sound waves and detect sound
Anthropogenic Noise Effect on Predation
They found on reef ecosystems that increasing noise pollution caused predation to increase
The prey cannot hear as well with all the noise