2. FROGS-Basic Facts
Frogs – amphibian - lay their eggs in water.
Eggs → Tadpoles → Adult Frogs
widely distributed- ranging from the tropics to subarctic regions
- greatest concentration - found in tropical rainforests.
approx. 4,800 recorded species - over 85% extant amphibian
species.
Tadpoles look more like fish than frogs, they have long finned
tails and breathe through gills.
Although frogs live on land their habitat must be near swamps,
ponds or in a damp place. This is because they will die if their
skin dries out.
Instead of drinking water, frogs soak it into their body through
their skin.
breathe through their nostrils while also absorbing about half
the air they need through their skin.
use their sticky, muscular tongue to catch and swallow food.
SCIENTIFIC
CLASSIFICATION
Kingdom Animalia
Phylum Chordata
Class Amphibia
Clade Salientia
Order Anura
3. FROGS - PARENTAL BEHAVIOR
Parental Care – Behavior exhibited by a parent towards its offspring – increases the
change of its survival.
Parental care – reported in only 10% of the species.
Among Amphibians, Parental care includes:
Attendance and protection of eggs and/or larvae
Transportation of eggs and/or larvae
Direct nursing of larvae
In Amphibians, however, compared with salamanders and caecilians , a greater
number of frogs have males in the attendance of eggs and/or larve.
4. Diversity : a)Protection by making nests
In Hyperolius obstetricans, females remains
with eggs on leaves overhanging streams. Upon
hatching, they kick their tadpoles out of jelly.
Phrynodon sandersoni (females) –attends eggs
on leaves of bushes at night.
In Chiromantis Xerampelina (females) –
moistens arboreal foam nest.
Male attendance occurs in some species of
Eletherodactylus ,of which E.coqui and
E.hedricki are territorial.
5. Rhacophorus malabaricus lay eggs on the
branches or tree leaves –hanging over the
pond- larvae fall into undergoing
metamorphosis
Rhacophorus schlegeli make burrow in moist
soil at pond edge – also make an exit tunnel
into the pond; hole –filled with foam-females
lay eggs;larvae developed –carried out by
liquid from the foam through exit tunnels into
the pond.
Hyla nebulosa –lays eggs in nest(dry leaves).
Eggs → small adults (larval form -absent)
Hyla resinfectris - makes use of holes in trees
– line the hole of tree trunk with beewax from
bee comb. Females lay eggs in these holes
when filled with rain water.
6. Centrolenella colymbiphyllum and C.valerioi are sympatric in Costa Rica.
Centrolenella colymbiphyllum (males)– attend egg clutches - on undersides of
leaves only at night . C.valerioi (males)– remains with eggs night and day.
No. of
clutches
% loss in
eggs
C. valerioi 112 7%
C.
Colymbiphyllum
152 23%
7. … apart from above illustrated
various above parental caring
methods …
b)Direct nursing..
Pipa Carvalhoi(female) – eggs carried on dorsum.
Australian myobactrachids(females) of genus
Rheobatrachus - eggs and larvae – developed in
stomach; young froglets emerge out from the mouth –
Gastric brooding.
European Alytes (males) - during oviposition,strings
of eggs – adhere to hindlimbs – periodically enters into
pond water – hatchlings released .
Hemiphractine hylids (females)- some eggs – present
in Dorsal pouch (see FIG-A);others adherent to
Dorsum(see FIG-B)
8. Buccal brooding/mouth brooding – In Leptopelis
brevirostris (females) and Rhinoderma darwinii
(males) (commonly k.a Darwin’s frog.) – fertilized eggs
transferred to vocal sacs –developed new frogs jump out
from parent’s mouth.
Dendrabates auratus (males) and Colosthetus
subpunctatus (males) carrying tadpoles externally.
Gastrotheca -special pouch in skin – fertilized eggs are
stored – undergo development.
9. CONCLUSION
Parental Care – occurs 10-15% in anurans : frogs exhibiting
the greatest diversity.
Frogs: lay eggs in water/land or abandon them;
Others exhibit parental care such as:
Attendance + protection of eggs and/or larvae
Transportation
Juveniles/Direct nursing
Putative benefits includes protection from :
Predators, desiccations
From fungus and other pathogens
Aeration of eggs
Provision of foods to the larvae(in some species)
Enhancing survival of eggs and larvae.
Parental cost includes:
Physical risks
Energetic costs
Decreased opprtunities for future reproduction
10. Lastly, Sources of embryonic and larval mortalities need to be carefully investigated.
INVESTIGATED
INFORMATION
+
DATA ON ENERGETIC &
REPRODUCTIVE COSTS
OF PARENTAL CARE
NEW INSIGHTS INTO
RELATIONSHIPS
BETWEEN :
Reproductive modes
Parental Behavior
Mating systems in frogs
providing
11. bibliography
Books referred:
Kentwood D.Wells(ed.)(2007).The Ecology and Behavior of Amphibians.Chicago:The
University of Chicago Press.
William E.Duellman(ed.)(1986).Biology of Amphibians.New York:McGrew-Hill
Professional Publishing and Co.
Sites referred:
www.lefo.net/documents/main/3klass/1kala/interesting_fact_about_frogs.html
www.defenders.org/frogs/basic-facts
www.smithsonianmag.com/science-nature/14-fun-facts-about-frogs-180947089
animals.about.com/od/frogstoads/a/tenfactsfrogs.html
www.biozoomer.com/2011/11/parental-care-amphibians.html?m=1
www.biodiversitylab.org
frogblogmanchester.fileswordpress.com