This document provides information about toads, including their distinguishing characteristics, classification, life cycle, and importance. It notes that toads have bumpy, dry skin without teeth or bulging eyes, while frogs have moist, smooth skin with teeth and protruding eyes. Toads lay eggs in long chains while frogs lay eggs in clusters. The document describes toad classification within the animal kingdom and provides details about a toad's internal and external morphology. It then outlines the stages of a toad's life cycle from mating and egg-laying to tadpoles and toadlets. The document concludes by discussing why toads are important as predators, for pest control, medicine, education, and research.

1. Bufo from latin,“Toad”.
Presentation by: Sushmita kant

2. True Frogs
(Family Ranidae)
Moist and smooth skin
Teeth in upper jaw
Eyes bulge out from the
body.
Long, powerful jumping
legs; most frogs have
webbed hind feet.
Eggs laid in clusters
True Toads
(Family Bufonidae)
Bumpy and dry skin
No teeth
Eyes do not bulge out
from the body; a poison
gland is located behind
each eye.
Shorter legs (for walking)
Eggs laid in long chains
(but a few toads give birth
to young ones
Frog v/s Toad

3. Toads do not have the sticky long tongues that frogs have; the toad has
to walk up to its food and cram it in its mouth

4. Scientific classification
Kingdom: Animalia
Phylum: Chordata
Sub phyllum: Vertebrata
Super Class: Gnathostomata
Class: Amphibia
Subclass: Lissamphibia
Order: Anura
Family: Bufonidae
Genus: Bufo
Classification

5. Phylum : Chordata (those animals with spinal cords)
Sub-phylum : Vertebrata (spinal cords protected by a
backbone)
Super Class : Gnathostomata (having a mouth with jaws)
Class : Amphibia (means “twin life” – part in water, part on
land)
Subclass : Lissamphibia (Modern amphibia without exoskeleton)
Order : Anura (means “tail-less”, Pentadactylous unequal limbs)
Family : Bufonidae (these are the True Toads)
Genus : Bufo (true toads)
Classification

6. Toads are mainly found in dry places but can be found in moist places also, and
almost on all the continents except in Polynesia and the island nation of
Madagascar, along with certain isolated South Pacific islands. They are most
abundant in the tropical regions
The common toad usually moves by walking rather slowly or in short shuffling
jumps involving all four legs. Nocturnal, It spends the day under foliage or beneath a
root or a stone where its colouring makes it inconspicuous.
Having no teeth, it swallows food whole in a series of gulps. They feed on Insects,
grubs, slugs, worms, and other invertebrates. In defence they releases toxins and a
bad-tasting secretion from its skin. These secretions make toads unattractive as
food to most animals.
Habit and Habitat

7. External Morphology
The head is broad with a wide mouth below the terminal snout which has two small
nostrils. There are no teeth.
The skin is dry and covered with small wart-like lumps.
Just behind the eyes are two bulging regions, the paratoid glands. They contain a
noxious substance, bufotoxin, which is used to deter predators.
The fore limbs are short with the toes of the fore feet turning inwards.
There is no external vocal sac.
The females are browner and the males greyer.

9. Internal Morphology
The toad’s nervous system, which consists of its brain, spinal cord, and nerves, is highly
developed.
The toad’s heart consists of two upper chambers, termed the right and left atrium and a
single lower chamber, which is termed a ventricle. Whereas tadpoles have 2 chambered
heart.
Frog can respire through skin or via simple sac-like lungs. But Do not possess either a
diaphragm or ribs, Whereas tadpoles have gills for respiration.
Capture prey, which is passed by way of the esophagus to the stomach. A small intestine,
large digestive glands, gall bladder, pancreas and liver, make up the remainder of the
digestive system. Both liquid and solid waste leaves the body through the cloacal vent.

10. Toads
Hibernation: They burrow down into the mud or leaf litter when it begins
to get cold and lower their bodily functions to near death and sit. They are
not freeze-tolerant and will die if they become too cold. warmer temperatures
are the cue for emergence from hibernation. Once they emerge, thawing
begins immediately.

11. Paratoid Gland: The parotoid gland (alternatively, paratoid gland) is an
external skin gland on the back, neck, and shoulder of toads and
some frogs and salamanders. It secretes a milky alkaloid substance to deter
predators. The substance, bufotoxin, acts as a neurotoxin.

12. Life cycle of Toads

13. Mating
- Adult toads often mate in the water after summer rains.
- During mating the male climbs onto the back of the female and wraps his front legs
around her. This clasp is, amplexus.
- Females are usually sexually mature at about three years old, while males are already
mature enough to mate at about two years old.
Eggs
- The female lays eggs through cloaca in strings or strands.
- Male release sperm over these eggs.
- The eggs develop for a period of days to weeks, depending on the water temperature.
As the temperature increases, so does the rate of development.
Toads and frogs usually reproduce by means of external
fertilization.
Life cycle of Toads

14. The average frog or toad lives for 7 to 14 years while some live to be 40.
Mating toads (amplexus)

15. Tadpoles
- Thousands of tiny black tadpoles hatch from the eggs in about a week and propel
themselves through the water using their tails.
-They breathe through gills and cannot survive out of water. Immediately, the
tadpoles begin eating algae and other plant material.
- Over the next month, the small tadpoles increase in size, grow legs and acquire
lungs, undergo metamorphosis.
Toadlets
-Toadlets are nearly adults.
- They have lungs, front and rear legs, but they still have a tail like tadpoles.
- Toadlets live on land but they are still fragile and will dehydrate quite easily so
frequently go into water.

16. In California, due to the popularity of “toad licking," it is illegal to possess
Colorado River Toads, which produce a powerful hallucinogen called
bufotoxin.
Male fire-bellied toads have nuptial pads, enlarged bumps on their first and
second fingers. These nuptial pads help aquatic frog hold on to females during
breeding.
Toads use their eyeballs to help swallow their prey.
When threatened, the horned toad shoots blood from it's eyes
panamanian golden toads
Fact file

17. Fire-bellied toad
Horned toad
The reproduction is unique in midwife
toads where males care about the eggs.

18. These toads produce a neurotoxin in glands on either side of their head dogs ingest
by mouthing or licking the toad. These can cause neurologic signs including:
increased heart rate, increased respiratory effort, bright red gum color,
hallucinations, and potentially even seizures.
Colorado River Toads

19. Bufo sumatranus
Bufo tihamicus
Bufo valhallae
Bufo cophotis
Bufo corynetes
Bufo variegatus
Bufo alvarius
Bufo aucoinae
Bufo bocourti
Bufo campbelli
Bufo canaliferus

20. –Predators and prey in the ecosystem
Toads and frogs are right in the middle of the food chain and provide a very efficient
transfer of solar energy.
They play an important role in consuming insects and are an important food source for
birds, snakes, and other animals throughout the food web.
–Pest control
They help control insects that may be agricultural pests or carry diseases such as West
Nile virus.
–Medicine
Frogs have been used extensively in medical research, and many Nobel prizes in
medicine and physiology have involved frog studies.
Why toads are important?

21. –Education and research
The chemical compounds found in the skin secretions of frogs and toads are
being studied for their human benefits – everything from non-addictive pain
killers to cancer cures. Frogs have been an important part of biology education
for centuries, and the African Clawed Frog (Xenopus laevis) is the modern day
“lab rat.”

22. Thank

23. Sushmita Kant
B.Sc.(H) Zoology, 3rd Sem
Roll no: 0382
Submitted to : Amitabh Mathur