Life – Reproduction in Animals
must have seen sometime, bird feeding their babies or dog playing with their
puppies or monkey hugging its baby. Do you wonder at the similarity between
animals and their babies? We observe that animal and their babies have same
characteristic and features. Both animal and their young ones have same pattern
of hair, skin, tail etc.
Why do animals have babies
similar to them?
living thing reproduce to replace their old and dying forms. If they do not
reproduce their form will disappear from the earth. Example: If cat does not
reproduce, they will not be seen in future after some time. So, reproduction is
vital process for every animal to continue its race.
is a process by which living organism produce another one of their own kind.
How do animals reproduce?
main ways of reproduction
By laying eggs
By giving birth to young ones
Animal That Lay Eggs
animals reproduce by laying eggs. These include insects, fish, frogs, snakes,
lizards, snails, birds and crocodiles.
builds nest to lay eggs. Birds nurture their eggs to keep them at the proper
temperature, before these eggs hatch into young ones.
eggs are protected by hard covering made of calcium carbonate called the shell.
Shell is porous that allows the transfer of gases through the shell. Within the
shell are the albumen (white) and the yolk (yellow). Albumen contains
protein that is necessary for development of growing bird and Yolk is
the source of food, contains the fat. The young bird will only develop at the
proper temperature, this happens only when bird sits on them for several days.
the baby bird hatches from the egg, they do not have feathers. So, the bird
feeds their young ones till their feather develops.
of the insects such as butterflies, grasshoppers, cockroaches and houseflies
lay eggs. The young ones when come out of eggs look very different from their
parent. During their growth, they keep shedding their outer layer or covering
of their body and gradually develop into adult. This process of shedding off
outer covering of the body i.e. skin by the baby insect during their growth is
baby cockroach or grasshopper that hatches from egg is called nymph. They do
resemble their parent but lack wings. After shedding their skin several times,
they turn into adult.
and housefly eggs when hatches, small worms come out called larva. The larva of
butterfly is called caterpillar and larva of housefly is called maggot.
Life Cycle of Butterfly
lay eggs on leaf and tiny worm like structure hatch from the egg called larva
(caterpillar). Caterpillar eats leaves all the time and becomes plump and
sluggish. When it cannot eat more, it covers itself from the thread that comes
out of the caterpillar’s body. This stage is called pupa. The
caterpillar undergoes many changes inside the cocoon. This change occurring in
the form, structure, or function of organism in the process of its growth or
development is called metamorphosis. After few weeks later, a beautiful
butterfly comes out of cocoon.
Life Cycle of Frog
lay eggs in water or wet place. Eggs hatches into small tadpoles. These
tadpoles look more like a fish rather a frog. Tadpole has no legs but has a
long tail and breathes through gills in water. They feed on pond weeds and gradually
turns into froglets and then into frog. An adult frog breathes through lungs.
turtle and snakes also lay eggs but do not give any parental care. Most of
their laid eggs are eaten by other animals. Among reptiles only crocodiles and
their relatives tend both eggs and babies. Crocodiles make nest in the ground
and lay eggs there. They carry their babies to the water body after the egg
hatches and took care of them for some time.
Animals that give birth to
animal give birth to young ones. Such animal are called mammals. This includes
animals such as dogs, cats, monkeys, tigers, cows, elephants, horses and
humans. The baby develops inside the mother’s body. After their birth they feed
on mother’s milk till they learn to feed by their own.
and dolphins lives in water but they give birth to young ones. Bat though a
bird gives birth to young ones.