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Herp Behavior

Herpetoculture

Pensacola Jr College

Sensory Receptors

w    Ear

    Tympanic membrane in amphibians that make sound

    Tympanic membrane on surface or in depression in reptiles, missing in snakes

w    Eye

    In amphibians best developed in frogs – definition for sharpness, size, movement

    Binocular vision in reptiles

Tympanum- bullfrog

Snake-lizard w/ ear opening

Chameleon Eyes

Sensory Receptors (cont’d)

w    Parietal / pineal eye

    In head dermis in amphibians

    Actually has retina in tuatara

    Detects light

w    Chemical receptors

    Taste buds more sensitive in amphibians than reptiles

    Jacobson’s organ in both

Pineal eye in tuatara

Jacobson’s Organ - rattlesnake

Sensory Receptors (cont’d)

w    Heat pits

    Along margins of jaws in pythons and boas

    2 large pits in pit vipers

    Overlap field in front of animal and surveys 180 degrees for changes in temperature

w    Skin receptors

    Temperature, touch, pain

Heat pits in green tree python

Heat pits in viper

Mating Ritual Behaviors

w    Salamanders: depend on physical courtship ritual, stereotyped display behavior

w    Frogs/toads: males emit species specific calls and clasp females

w    Reptiles: Males follow and court females

Functions of Coloration

w    Protective function

w    Sex/species recognition

w    Thermoregulation

w    Radiation shield

Color as Protection

w    Protection from predation, camoflauge

w    Protection from detection by prey, concealment

w    Color matches/changes:

    Dark forest= uniform dark

    Open forest= blotchy

    Open grassland= striping

    Desert= soil colors

Frog camouflage

Camouflage in tree frog

Color as Protection (cont’d)

w    Flash colors = bright patches of contrasting colors, exposed only in movement

w    Head mimicry = tail resembles head; distraction

w    Advertisement= bright venomous warning colors

w    Batesian mimicry= false advertisement

Flash colors –
fire-bellied toad

Advertisement of toxicity

Batesian mimicry

Sex/species Recognition

w    Color in many herps is the only way for a female to recognize a male or a male to recognize another male of their own species

w    Important for solitary animals, as most herps are

Dimorphism in bullfrogs

Color in Thermoregulation

w     Darkest individuals absorb and lose heat most rapidly

w     Many herps make their skin darker to absorb heat and lighter to retain heat

w     Lizards regulate on 24 hr cycle

w     Amphibians use light, temp, humidity as color change stimuli

Color as Radiation Shield

w    Birds and mammals have fur or feathers, herps depend on melanin in skin to protect from radiation

w    Darker colors provide more protection, and color darkens with sunlight/radiation exposure