Frogs

Question 1

Amphibian Orders

Answer 1

Order Anura
- Frogs and toads

Order Caudata
- Salamanders and newts
Order Gymnophiona
- Caecilians (wormy boys)

Question 2

Anura features

Answer 2

• short body
• protruding eyes
• large hindlimbs
• lifecycle = egg -> tadpole -> adult (mostly external fertilization

Question 3

Frog Families (6)

Answer 3

1. Pelodryadidar (tree frogs)
2. Myobatrachidae (ground frogs)
3. Limnodynastidar (foam-nesting ground frogs)
4. Microhylidae (microhylid frogs)
5. Ranidae (true frogs)
6. Bufonidae (toads)

Question 4

Pelodryadidae

Answer 4

‘Tree Frogs’

• ground and tree dwelling
• standard breeding
• Australia/PNG distribution

Question 5

Myobatrachidae

Answer 5

‘Ground Frogs’

• ground dwelling
• broad environments
• standard (and some unique) breeding strategies
• Australia/PNG distribution

Question 6

Limnodynastidae

Answer 6

‘Foam nesting’

• broad environments
• standard breeding from a foam nest
• Australia/PNG distribution

Question 7

Microhylidae

Answer 7

‘Microhylid Frogs’

• Restricted to NE Aus
• Terrestrial breeding (tadpole grows inside egg)
• Global tropic and subtropic distribution

Question 8

Ranidae

Answer 8

‘True Frogs’

• classic looking frogs
• Global distribution (only one species in Aus)

Question 9

Bufonidae

Answer 9

‘Toads’

• introduced species in Aus
• global species variation
• pond breeders

Question 10

Impacts of toads

Answer 10

1. poison animals that eat them
2. eat animals smaller than them
3. outcompete native species
4. indirect effects (eg. resource competition, food chains)

Question 11

There is frog diversity when it is…

Answer 11

• warm
• wet
• mountainous

Question 12

Wet tropics

Answer 12

• rainforest on mountains
• coastal lowlands
• isolated rainforest (changes in distribution over time)

Question 13

Species distribution depends on…

Answer 13

1. where the habitats are now and where they used to be (suitability)
2. where barriers are now and where they used to be
3. competition

Question 14

Frog basics

Answer 14

• hopping movement (few walk)
• ectotherms
• moist skin (water exchange through skin)
• minimal diet specialisation (primarily invertebrates but will eat anything)
• primarily nocturnal (in AUS)

Question 15

Frog mating

Answer 15

• mate choice dominated by calls
  (only males call)
• calls made up of pulses |||| …. |||| …. ||||
• differences in duration, frequency, pitch, etc.

Question 16

Mating calls

Answer 16

1. attract mates (mff)
2. aggression (mfm)

• calls are sometimes combined (may start out with one call for female and end in call for male

Question 17

Species discrimination

Answer 17

choosing a male from the right species

Question 18

Sexual selection

Answer 18

choosing a preferred male

eg.

• pitch can indicate size
• temporal properties indicate energy expenditure

Question 19

Standard breeding

Answer 19

1. multiple eggs surrounded by jelly in water
2. tadpoles form and leave eggs
3. tadpole swims around (has gills)
4. develops hind legs
5. eventually develops body, loses tail and becomes a frog (leaves water)

Question 20

Pros and cons of standard breeding

Answer 20

+ huge number of eggs (little investment)
+ aquatic environments have a lot of food

• NEED water for some period of time
• lots of predation in aquatic environments

Question 21

Pros and cons of other breeding strategies

Answer 21

+ removed from high predation of aquatic environment
+ higher success per egg (parental care)

• smaller clutch size
• more parental investment
• terrestrial predation (managed by parents)

Question 22

Rheobatraccus spp

Answer 22

gastric breeding frog

• egg fertilized externally
• egg swallowed after fertilization
• jelly on egg ceases gastric acid production
  eggs hatch into tadpoles
• tadpoles develop and frog emerges through mouth

Question 23

Frog habitat types

Answer 23

• open forest
• arid areas
• swamps
• rainforest

Question 24

Open forest frogs (woodlands)

Answer 24

• high DIVERSITY, high ABUNDANCE
• dry habitat with short periods of flooding
• explosive breeding during rain
  - rapid tadpole development
  - ephemeral water body survival
• refuge sites during the dry season (in trees, dry cracks, covered)

Question 25

Arid area frogs (dryland)

Answer 25

• underground living cause of heat
  - aestivation (dormant state triggered by water and
  food shortage)
  1. borrow underground when moist (water
  conserving cocoon)
  2. suppress metabolism by 80%
  3. wait for heavy rain and emerge
  - rapid tadpole development (due to water
  evaporation)

Question 26

Wetland frogs (permanent swamps)

Answer 26

low/moderate diversity, abundant species, high endemism

• high predation environment (prey on tadpoles)\

Question 27

Rainforest frogs

Answer 27

• stream frogs
  - live in forest and visit stream (around streams)
  - torrent frogs - live near waterfalls (eggs on rocks
  with flowing water)
  -