Herpetology: Biogeography, Physiological Ecology, Reproduction, and Feeding

Vocabulary flashcards covering biogeography, physiological water and temperature regulation, reproductive strategies, and feeding modes in amphibians and reptiles.

Biogeography

The geographic distribution of plants and animals.

Vicariance

A process where a natural or artificial barrier splits a continuous population into two or more discontinuous populations.

Transoceanic dispersal

A dispersal mechanism mostly involving rafting atop pieces of wood or piles of vegetation floating on water, often initiated by storms and carried by ocean currents.

Refugia

Areas where a population can survive through an extended period of unfavorable conditions, with boundaries that can contract and expand according to the environment.

Continental islands

Islands that possess a geologic connection to a landmass.

Oceanic islands

Usually uplifted limestone or volcanic islands that lack any connection to a mainland.

Ecomorphs

Species that have independently evolved similar morphology, habitat use, and behavior across different environments or islands.

Sky islands

A unique type of refugium typically restricted to mountaintops due to warming climate, where gene flow between isolated high-elevation populations is severed.

Secondary contact

The meeting and potential interaction of previously isolated populations when climatic cooling causes refugium or sky island boundaries to expand into each other.

Biophysical ecology

The study of how animals exchange heat and water with their environments.

Preformed water

Water that an animal obtains directly through the ingestion of food.

Metabolic water

Water yielded from cellular respiration and metabolism when hydrogen from digested food combines with oxygen.

Cutaneous resistance

The amount of time required for water to diffuse across the skin, measured in seconds per centimeter ($\text{s/cm}$).

Heliothermy

A mechanism of thermoregulation wherein herps regulate their body temperature using solar radiation.

Thigmothermy

A mechanism of thermoregulation wherein herps regulate their body temperature via conductive heat transfer from a substrate.

Kleptothermy

A form of thermoregulation in which ectotherms utilize metabolic heat produced by endotherms, such as rattlesnakes overwintering in mammal dens.

Inguinal amplexus

The ancestral mating clasp of anurans in which the male grasps the female around the waist.

Axillary amplexus

A mating clasp in anurans in which the male grasps the female directly behind her forelimbs.

Cephalic amplexus

A mating clasp in anurans where the male positions himself far up on the dorsum of the female and grasps her head.

Orton Type 1 tadpole

Tadpole morphology characterized by wide, slit-like mouths without keratinized mouthparts and paired spiracles, found in Pipidae and Rhynophrynidae.

Orton Type 2 tadpole

Tadpole morphology featuring a single midventral spiracle and mouthparts more complex than Type 1, but still lacking keratinized mouthparts, found in Microhylidae.

Orton Type 3 tadpole

Tadpole morphology characterized by keratinized mouthparts and midventral spiracles, found in Ascaphidae, Leiopelmatidae, Bombinatoridae, and Alytidae.

Orton Type 4 tadpole

Tadpole morphology possessing keratinized mouthparts and sinistral spiracles, representing all frogs not classified under types 1 through 3.

Genotypic sex determination (GSD)

A mechanism where sex is established by genotype; the sex-determining region (sry) gene on the Y chromosome triggers testes development, while ovaries develop in its absence.

Temperature-dependent sex determination (TSD)

A mechanism where incubation temperature during the middle third of embryonic development determines the differentiation of gonads into testes or ovaries.

5a-reductase

The enzyme that initiates the developmental cascade leading to testes formation at male-producing temperatures in TSD reptiles.

Aromatase

The enzyme that initiates the developmental cascade leading to ovary formation at female-producing temperatures in TSD reptiles.

Charnov-Bull model

A model proposing that temperature-dependent sex determination is evolutionarily advantageous when male and female fitness levels peak under different developmental incubation temperatures.

Parthenogenesis

A form of asexual reproduction in reptiles in which all-female populations produce genetic clones of themselves without male fertilization.

Kinetic feeding

A terrestrial feeding mode involving cranial kinesis (significant mobility of skull bones) utilized by snakes to consume prey.