Looks like no one added any tags here yet for you.
closeness, dispersal
rate of gene flow to a function of the ______________ of the population and the _____________ tendency of the species
classical biological concept
genetically distinctive populations of individuals isolated reproductively from all other populations
subspecies
population of a particular region genetically distinguishable from other such populations and capable of interbreeding with them
Ex: prairie racerunner and six-lined racerunner
cline
gradual and continual change in a character by a series of populations or throughout the range of a species
- usually along a geographic or environmental gradient
- Ex: plastral markings in painted turtles
latitudinal changes
changes in body weight (Bergmann's Rule) and changes in body color
1. climate
2. availability and access to resources
3. dispersal abilities
3 major factors that influence geographic distribution of amphibians and reptiles
feeding, thermoregulation, and predator avoidance
3 purposes for daily movement
more (breeding, hibernation, and habitat utilization)
seasonal movement is _________ extensive
dispersal
movement outward from the home range, often implies colonization (undirected movement to locations unknown by the dispersing animals)
benefits of dispersal
1. minimizes intraspecific competition
2. increased contact with individuals of other species/unrelated
3. decreased inbreeding
costs of dispersal
1. lacking food resources and possibly shelter
2. increased unknown predators (increased predation risk)
piloting
ability to recognize land marks within home range
compass orientation
sense of direction, independent
true navigation
internal map, ability to move toward any location
visual orientation
using polarized light to navigate
celestial orientation
using stars to navigate
visual, wave, magnetic
Green Seas Turtles use ________ cues, _______ orientation, and ____________ orientation to navigate
stars, moon
Using _________ and _________ helps Green Sea Turtle hatchlings find the ocean when on the beach
Green Sea Turtles use _________ orientation to move away from shore into the sea
magnetic
Once Green Sea Turtle hatchlings are deep into the ocean, they use ____________ orientation to help with navigation
Sea Turtles orient use waves
Experiment where:
- turtles were tethered inside a floating orientation arena
- results:
> turtles swam into waves when waves were present
> when waves were absent, turtles didn't know which way swim (random)
Sea Turtles detect magnetic fields
Experiment where:
- turtles were tethered inside a floating orientation arena
- half the turtles swam under Earth's magnetic field, the other half swam in a reverse magnetic field
- results:
> turtles swimming in Earth's magnetic filed swam east to northeast (normal direction they follow off shore)
> turtles tested in reverse filed swam the opposite direction
larger (seen in the Spiny Lizard)
males tend to have __________ home ranges than females
males
do males or females tend to have a more dynamic home range throughout the year?
expensive
defense is usually very _____________
turtles (freshwater)
what herp group tends to have the largest home ranges?
caudates (anurans are 2nd)
what herp group tends to have the smallest home ranges?
territorial defense
When an animal or group of animals protects its territory from others by marking it with pheromones
site defense
reducing the likelihood of attack against a particular site, a male defends one "thing" (rock, basking log, food item nesting site)
True
T or F: site defense is more common than territorial defense
insects
frogs and salamanders feed on...
plants and animals (vertebrates and invertebrates)
turtles feed on...
animals (vertebrates and invertebrates)
squamates feed on...
hyoid bone
piece of cartilage that serves as a rigid base of the tongue
chameleons
the hyoid bone is seen in...
Opisthoglyph
rear-fanged snakes, angled backward utilized to inject venom into the puncture wound
Proteroglyph
forward grooved fangs in front, hollow filled with neurotoxin (seen in Common Cobra)
Solenoglyph
hinged fangs, fold against roof of mouth, hollow filled with hemotoxin (seen in Vipers)
ambush (sit-and-wait) and active (wide foraging)
2 foraging modes
ambush foraging
- less energy spend on searching
- more energy spent on capturing prey
- specialized eyesight and organs
- rely on cryptic coloration
active foraging
- searching for prey
- visual and chemical cues used for prey detection
prey availability, predation risk, social interactions, habitat structure
4 external factors influencing foraging behavior
hunger level, amount of learned experience (coupled with age), genetics, dietary preference
4 internal factors influencing foraging behavior
sensory limitations, morphological characteristics, physiological characteristics (too cold/too warm), behavioral
4 phylogenetic factors influencing foraging behavior
visual prey detection
- used by ambush predators
- need large, developed eyes
- discriminate prey based on size and shape
- binocular perception
- most align their head or entire body axis with that of prey before attacking
olfaction
- epithelium in nasal cavity detect airborne odors
- long distance detection system
- main sense of salamanders and lizards
vomerolfaction
- sensation to high molecular weight compounds which are transported to oral and nasal cavities via the snout or tongue
- short distance detection system
- main feeding sense in salamanders, lizards, and most snakes (bifurcated tongue in snakes provide directionality of info)
taste
- helps distinguish food items from non-food items (accept and swallow or reject and spit out)
Jacobson's organ
Sense organ on snake's roof of mouth which detects airborne chemicals
- located behind nose and infront of eyes
- when tongue is retracted back into mouth, the split tongue fits into the grooves in the organ which lies along nerves
- nerves transmit info to the brain
tactile prey detection
mechanoreceptors in skin
- in several species, flaps of skin are highly innervated and also help
- Ex: lateral line system in aquatic amphibians
thermal prey detection
IR is sensed in nerve endings in the skin of the head which are located inside pit organs
- pit organs provide a binocular perception field
- most effective for nocturnal species that feed on mammals and birds
1. biting/grasping
2. constriction (boas and pythons)
3. injected venom
4. filter feeding (tadpoles, large buccal cavities)
5. suction feeding (common in snapping turtles and hellbenders)
6. projectile tongues
6 prey capturing techniques
1. feeding adaptations of animal
2. size of animal and prey-capturing methods
3. habitat
4. relative abundance and size of prey available at the time of feeding
food habits depend on...
communication
transfer of info from signaler to a reciever
visual communication
communication through body movement and colors
acoustic communication
communication through sound (vocalization, rubbing body parts together)
chemical communication
communication through glandular secretion odors, well developed in salamanders, lizards, and some snakes
tactile communication
communicating through touching
locate and message mates in complex environment
benefits of communication
ambystomatids
the cloaca nudging waltz is seen in...
chemical (pherohormones produced by courtship glands), tactile (nose-tapping, biting, slapping, rubbing)
salamanders use ____________ and ____________ cues to communicate
plethodontids
the tail straddling waltz is seen in...
acoustic (calls), visual (bright coloration)
frogs use ____________ and ____________ cues to communicate
advertisement
type of frog call to attract conspecific
reciprocation
type of frog call females use to respond to males (rare)
release
type of frog call used when male is being amplexed by another male
distress
type of frog call used as a predator alarm
visual (head bobs), tactile (biting, tickling, ramming), chemical (cloacal secretions, special glands on the bridge of their shells)
turtles use ____________, ____________, and ___________ cues to communicate
visual (dewlap coloration), chemical (pherohormones), tactile (tongue flicking, body scratching)
lizards use ____________, ____________, and ____________ cues to communicate
tactile
snakes use __________ cues to communicate
interspecific competition
competition between members of different species
intraspecific competition
competition between members of the same species
evaporative loss (helps maintain moisture during cold months)
snakes congregate during hibernation to minimize...
breeding aggregations
collective calling to attract female to breeding site
predation
____________ is the greatest cause of mortality
escaping detection
predator avoidance technique: not being present when a predator is searching for prey
crypsis and immobility
predator avoidance technique: resemble a random sample of certain aspects of the environment (usually immobile)
- Examples:
1. blending in
2. polymorphic coloration
3. changing body shape (Vine Snakes and Surinam Toads)
aposematic coloration
predator avoidance technique: bright coloration in animals that produce noxious or lethal chemicals from skin glands (Poison Dart Frogs)
postural warning
predator avoidance technique: assuming several defensive postures to "scare" predators
- Unken Reflex in Fire Belly Toads
- Large red eyes in Red-eyed Tree Frog
batesian mimmicry
predator avoidance technique: occurs when a nontoxic species mimics a toxic or protected one
Ex: Northern Scarlet Snake mimics the Eastern Coral Snake
Ex: Amazonian Leaf Litter Frogs
Ex: Red morph of Redback Salamander mimics Red Eft stage of Eastern Newt
Mullerian mimicry
predator avoidance technique: both potentially dangerous species resemble each other (both species are the model and mimic)
escaping
predator avoidance technique: running away or hiding:
1. Skin, armor, and spines
2. Chemical defense
3. Death Feigning
4. Tail Displays and Autonomy
5. Schooling
Microparasites and Macroparasites
agents of infectious disease
Microparasites
- reproduce inside of host
- bacteria, viruses, protists, and fungi
Macroparasites
- reproduce outside of host
- helminths and anthropods
- intensity-dependent pathology
extinction
parasites rarely drive their hosts to _____________
inbreeding, stochasticity
____________ and ____________ drive disease-induced extinction in small populations
1. Chytrid Fungus
2. Ranivirus
3. Rib Virus (Ribeiroia ondatrae)
3 parasites of conservation concern in herps
Chytrid Fungus
a pathogenic fungus that has a a devastating impact on frogs
- attacks keratinized tissue (mostly in adults)
- causes lethargy, paralysis, skin lesions, loss of pigment
- leads to impaired osmoregulation and cutaneous respiration
Ranivirus
a pathogenic fungus infecting ectothermic vertebrates (herps and fish)
- most virulent forms: Ambystoma Tigrinum Virus (ATV) and Frog Virus 3 (FV3)
- causes organ destruction (liver, spleen, kidney)
- signs of death: edema, redness, hemorrhages, ulcerations
- mosquitos infect lethargic turtles
Rib Virus
a parasitic fluke (platyhelminths) that targets limb tissue
- cycle of deformity:
1. aquatic snails
2. Amphibians
eutrophication
A process by which nutrients, particularly phosphorus and nitrogen, become highly concentrated in a body of water, leading to increased growth of organisms such as algae or cyanobacteria
biodiversity crisis
loss and reduction in diversity at all levels (genetics --> ecosystems)
extinction
rate has growth exceeded the "normal" historical rates
1. habitat modification, fragmentation, and loss
2. harvest
3. introduction of exotic species
4. management tools
human impacts on herp conservation
habitat alteration/fragmentation and increased mortality due to road kills (leads to skewed sex ratios)
consequences of human-influenced habitat modification
commercial exploitation of herps
1. Consumption (frog legs)
2. Luxury Trade (American Caimans for leather)
3. Pet Trade (box turtles)
introduction of exotic species examples
1. Black and Norway Rates --> great impact on islands (lizards, tuataras, tortoises)
2. Domestic Cats --> damage in suburban and rural areas
3. Herbivores (goats and rabbits) --> change vegetation
leapord
American bullfrogs reduced ___________ frogs in California by 33% and in Arizona
minimum viable population (MVP)
minimum area required for a population or species to survive