-
What are the five extant groups of Reptilia?
- Aves - birds
- Squamata - snakes, lizards and worm lizards
- Crocodilia - crocodiles, alligators, gharials and caiman
- Testudines - turtles, tortoises and chelonia
- Rhyncocephalia - tuatara
-
What is the binomial name for the tuatara?
- Sphenodon punctatus (Least Concern)
-
Example of crocodilia species
- Crocodylus porosus(Saltwater crocodile)
-
Example of testudine species
- Chelonia mydas(Green sea turtle)
-
Example of squamata species
- Varanus komodoensis
- (Komodo dragon)
-
What kind of skull do reptiles have?
- Diapsid
- (except testudines appear to be anapsid - no cranial kinesis)
-
What group do the Crocodilia and Testudines form?
Archosauromorpha
-
What group do the Squamata and Rhynchocephalia form?
Lepidosauromorpha
-
Which is the most diverse of the extant orders of reptiles?
- Squamata Lizards - 6100 spp
- Snakes - 3400+ spp
-
What types of dermal structures are found on reptilian skin?
CHECK THIS
- Scales - all reptiles
- Scutes - just turtles
- Osteoderms - crocodilians lizards and turtles
- Filaments (Archosauromorpha)
- Feathers - pterosaurs (Archosauromorpha)
-
What are the primary modes of thermoregulation?
- Heliothermy - heat from the sun
- Thigmothermy - heat conducted via substrate
- Kleptothermy - heat gained from endotherms
( Metabolic - generally restricted to large reptiles)
-
What are the three main modes of sex determination?
- Genetic
- Temperature
- Parthenogenesis
-
What are the types of temperature-based sex determination?
- 1a - males at low temp, females at high temp
- 1b - males at high temp, females at low temp
- 2 - males at intermediate temp, females at high AND low temps
-
What is viviparity and where is it found in the reptiles? Give an example.
- Live-bearing
- Squamates such as Zootoca vivipara (Common lizard)
- Typically in colder climates
- Was also found in Icthyosauria and other marine reptiles
-
What are the features of a reptilian egg?
- Amniote
- Leathery
- Watertight -prevent water loss
- Breathable - gas exchange
-
What locomotion styles are exhibited by reptiles?
- Walking/Running - alternate limbs thrown forward
- Swimming - turtles 'fly', undulate sinusoidally ~ e.g. sea snakes
- Gliding - e.g paradise tree snake
- Sidewinding Running on two legs e.g. jesus lizard
-
What is meant by Biogeography?
The study of the evolutionary and ecological processes leading to the distribution of organisms
-
What mechanisms do reptiles disperse by?
- Own movement
- Rafting
- Via another organism
-
What is meant by vicariance?
the geographical separation of a population, typically by a physical barrier such as a mountain range or river, resulting in a pair of closely related species.
- -separation of continents
- -formation of mountain ranges
- -gain/loss of land bridges
- -island formation and erosion
- -landslide
-
What factors tend to influence squamate species richness and diversity?
- Temperature
- Moisture
- Habitat structure
-
What is island paleoendemism?
Species that were once widespread but are now restricted to a smaller area.
-
What types of signalling do reptiles display? Give examples.
- Visual - e.g. turtles headbob
- Chemical - e.g. snake tongue, squamate femoral pores → for marking territory
- Acoustic - e.g. crocodilians, nocturnal geckos
- Tactile - e.g. testudines → biting, head rubbing etc
-
What constraints are there on signalling in reptiles?
- Body size: smaller animals have shorter range
- Physiology: temperature and energy cost
- Ecology: Predation risk of signal
-
Explain the feeding niche of an American Alligator.
-Resource abundance, patchiness, renewal rate.
-Movement within and between patches
-Home range size
- Feeding niche example: Ambush predator of vertebratesResources: abundance – variable
- patchiness – variable
- renewal rate – low
- Movement:
- within patch – low
- between patches – variable
- Home range size: variable (shifting activity centre)
- Latin: Alligator mississippiensis
-
Explain the feeding niche of a Galapagos Marine Iguana
-Resource abundance, patchiness, renewal rate.
-Movement within and between patches
-Home range size
- Feeding niche example: Marine folivore
- Resources:
- abundance – high
- patchiness – low
- renewal rate – moderate
- Movement:
- within patch – low
- between patches – low
- Home range size: small
- Latin: Amblyrhynchus cristatus
-
Explain the feeding niche of a Western blind snake
-Resource abundance, patchiness, renewal rate.
-Movement within and between patches
-Home range size
- Feeding niche example: Ant and termite specialist
- Resources: abundance – variable
- patchiness – high
- renewal rate – variable
- Movement:
- within patch – low
- between patches – variable
- Home range size: variable
-
Explain the feeding niche of a Leatherback sea turtle
-Resource abundance, patchiness, renewal rate.
-Movement within and between patches
-Home range size
- Feeding niche example: Predator - Jellyfish specialist
- Resources:
- abundance – variable
- patchiness – high
- renewal rate – low
- Movement:
- within patch – low
- between patches – high
- Home range size: Extremely large (Nomadic lifestyle)
- Latin: Dermochelys coriacea
-
What assumptions can be made about Therapods and Pterosaurs and Ichthyosaurs from fossil evidence?
Therapods and Pterosaurs: parental care
Icthyosaurs: viviparous
-
What is meant by adaptive radiation?
process in which organisms diversify rapidly from an ancestral species into a multitude of new forms, particularly when a change in the environment makes new resources available, creates new challenges, or opens new environmental niches
-
What is meant by caudal autonomy? What types are there?
- Tail Breakage
- Intervertebral: Break between vertebrae. Involuntary. Does not regenerate.
-
What type of teeth do squamates have?
- Acrodont - lie in shallow socket, replacement teeth adjacent to active teeth
- Pleurodont - teeth attached to inner side of the jaw, replacement is continual
-
What are the different ways reptiles can shed?
- Patches - lizards
- Entire skin plus eye scale- snakes
- Individual scutes/cells/ small groups of cells - crocodiles and turtles
-
What are ISOs and which group has them?
- Integumentary Sensory Organs
- Crocodilians
- Crocodiles and Gharials have them nearly all over while Alligators and Caiman have them on their face
-
What are DCUs and which group has them?
- Dermal Chromatophore units - pigment containing and light reflecting cells
- Squamates - e.g. Chameleons
-
What mechanisms of water gain are there?
- Drinkingpuddles/streams/lakes
- surface collection on top of salt water
- transport via specialised cells
- EatingMetabolic Water
- addition of water molecules to hydrogen → oxidation of starch, fat, proteins
- → fat reserves mean they can survive long time without eating or drinking
-
What mechanisms of water loss are there?
- Evaporation
- Respiration - intrinsically linked to temperature since they will pant to cool down
- Excretion - semi solid mix of uric acid and faeces via cloaca
- Salt Glands - causes salt loss
-
What are thermoregulators?
Actively adjust behaviour or physiology to affect body temp
-
What are thermoconformers?
No active regulation
-
Why is ectothermy efficient?
- less energy required overall
- high conversion rates (energy devoted to growth and repro)
-
What are "reptiles"?
- Amniotes
- Exclude mammals and birds
-
What are the two types of island?
- Continental - connections to mainland may occur with changes in sea level
- Oceanic - volcanism or reef-uplift
-
What are the common features/processes of fauna on islands?
- Gigantism/Dwarfism
- E.g. glapagos giant tortoises vs. virgin islands dwarf gecko
- gigantism as a result of food size
- dwarfism as result of interspecific competition
- Adaptive radiation e.g. Anolis lizard in Caribbean
- Island paleoendemism
- e.g. Galapagos iguanas or tuatara of NZ
-
How do sea turtle hatchling find their way to the right place?
- Light - on surface of water
- Magnetic cues
- Wave orientation - motion sense
- → Internal compass
-
What type of mating systems are there?
- Scramble Competition
- - e.g. red garter snake
- Mate searching
- - solitary reptiles
- Mate Guarding
- - e.g. European Adder
- Leks and lekking- are used by males for communal display in breeding season
- - e.g. marine iguana
- Resource defence- males defend and are of resources to monopolise females
- - e.g. ornate tree lizards
-
What are some of the results of sexual selection acting on reptiles?
- Polyandry and sperm competition
- Sexual dimorphism
- ♀
typically larger in snakes and turtles - ♂ typically larger in crocodilians
- large variation in lizards
- Female choice
- - select mate based on pheremones, display, other fitness cues etc.
- Male competitive ability e.g. leks, resource guarding etc.
-
What does the movement through a habitat vary based on (in terms of niches).
- Varies based on diet
- (Affects home range size)
-
What pieces of information does a feeding niche incorporate?
- Type of prey or feeding strategy (e.g. herbivore, scavenger)
- Resources → abundance, patchiness, renewal rate
- Movement patterns → within and between patches
- Spacing system/home range sizes (e.g. small, variable, nomadic)
-
What are the different strategies of snakes?
- Pit organs
- Constrictors
Venom - - Elapines ~ short front fangs, neurotoxins
- - Vipers ~ hinged fangs, haemotoxins, anticoagulants, necrotising
-
What are squamate and testudine hearts like?
- partial left right division
- 3 chambered (2 atria and 1 ventricle)
- 2 aorta
- → incomplete separation of oxygenated and deoxygenated blood
→ helps with redirecting blood flow for thermoregulation
-
What ear bone do squamates have?
- Stapes
- (eardrum often reduced or absent)
-
Which groups are in Acrodonta?
- Chameleons and Dragons
- (rest are plurodont?)
-
What adaptations do the chameleons have?
- casques/horns/crests
- colour change
- tongue projection
- eyes work independently
- locomotion keeps spine straight
- feet as grasping pads
-
What is an adaptation of the iguana for its herbivorous diet?
- Colon is partitioned to slow passage of food
- Contains diverse microbiome
-
How are lizard skulls different to snake skulls - in terms of their prey?
- Lizard skull adapted to crush and grab prey
- Snake skull adapted to engulf prey
-
What are the general defining features of venomous vs non-venomous snakes?
-
What are some of the adaptations to different lifestyles of snakes?
-
What is an important feature of crocodilians for their prey choice and aquatic lifestyle?
- Robust secondary palate
- → breathing with tip of nose while submerged
- → protects brain when eating sharp food
-
What kind of teeth do crocodilians have?
- Thecodont
- - rooted in jaw similar to mammals
- Polyphyodont → continually shed and replaced
-
How many eyelids do crocodilians have?
- 3
- → nictating membrane cleans eye on land and protects while underwater
-
In what way is the crocodilian heart specialised?
- 4 chambered heart - complete division
- 2 aortas
- Valve to allow for mixing of oxygenated/deoxygenated blood and to prevent flow to lungs when underwater for long period of time
-
What type of sex determination is exhibited by crocodilians?
- Temperature based
- 1b→ males at high temp
- 2 → males at intermediate temp
-
Which crocodilians teeth fit inside their mouth?
Alligators and (most) Caiman
-
What is butt breathing and in which group does it occur?
How does it work?
- Cloacal Breathing
- in some pleurodires - side-necked turtles
- Have a pair of bursae lined with papillae → sites of gas exchange
- Swims with cloaca open & pumps water in and out
- E.g. Mary River Turtle
-
What are the features of male reptiles' reproductive morphology?
- Squamates: hemipenes
- Testudines: single penis → large to reach under plastron of female
-
What method(s) of sex determination do testudines use?
- Both Genetic Sex Methods
- → XY or ZW
- Temperature Based
- → 1a - males at low
- → 2 - males at intermediate
-
What is the name of the group "side necked tutles"?
- Pleurodira
- E.g. West African Mud Turtles
- E.g. Madagascan Big-Headed Turtles
-
What are some of the factors considered by the IUCN for the red list?
- Population size
- Mature individuals capable of reproduction
- Generation - time taken to breed and reach maturity
- Reduction in population
-
What are the red list categories?
- LC - least concern
- NT - Near Threatened
- Threatened - including vulnerable, endangered and critically endangered
- EW - extinct in the wild
- EX - extinct
- DD - data deficient
- NE - not evaluated
-
What classifies as Vulnerable on the red list? (critera and example)
- Reduction in pop size of >50% over last 10 years/ 3 generations → where cause is known and reversible
- Reduction of >30% where cause is unknown
Leatherback Turtles
-
What classifies as Endangered on the red list? (critera and example)
- Reduction in pop size of >70% over last 10 years/ 3 generations → where cause is known and reversible
- Reduction of >50% where cause is unknown
- Loggerhead Turtles
- Tiger Chameleon
-
What classifies as Critically Endangered on the red list? (critera and example)
- Reduction in pop size of >90% over last 10 years/ 3 generations → where cause is known and reversible
- Reduction of >80% where cause is unknown
- Slender-snouted crocodile
- Galapagos Pink Iguana
-
What does extinct in the wild mean? Example.
- Only known to exist in captivity
- OR naturalised population outside of historical range
- Christmas Island Blue-tailed Shinning Skink
- Christmas Island chained gecko
-
What does extinct mean? Example
When there is 'no reasonable doubt' that the last individual has died
Pinta island giant tortoise
-
What percentages of reptiles are data deficient and not evaluated?
-
What are the primary threats to reptiles?
- Habitat modification and destruction
- Invasive species
- Disease
- Pollution
- Exploitation → pets and science
- Climate Change
-
What is a particular threat to sea turtles?
- Loss of critical habitatsNeed different habitats for different life stages
-
What problems can invasive/introduced reptiles cause? Give examples.
- Predation: e.g. brown tree snake on Guam, burmese python in Everglades
- Competition: leaf-toed gecko vs. house gecko in Barbados
-
What is parasite spillover?
The introduction of parasites via invasive species or captive release.
-
What effects does pollution have on reptiles?
- Consumption and entangling
- Toxin bioaccumulation
- Endocrine disruptors (e.g. causing sex change)
- Noise pollution
-
What are some of the problems associated with climate change, especially in reference to reptiles?
TSD - temp sex determination will give wrong ratios of genders if temp changes
- Warmer + wetter → higher humidity and flooding
- Warmer + drier → aridity and forest fires
|
|
