Answer 1:
Scientists agree on where the first domestic
chickens came from, saying that all chickens can
be traced to the same ancestors - the Red
Jungle Fowl from Asia. They were probably
bred from this particular subspecies more than
8,000 years ago.
The male Red Jungle Fowl looks a lot like a
storybook rooster but it is not identical to the
domestic chicken we know. Man has managed to
cultivate animals for over 10,000 years. Farm
animals (cows, pigs, horses) as well as domestic
cats and dogs have been bred by humans in a way
that has changed them from their wild ancestors to
suite mans needs. This process of change is
actually what we know as evolution. In
nature, living things evolve through changes in
their DNA. In the chicken, like in other
animals, DNA from a male sperm cell and a female
ovum meet and combine to form a zygote --
the first cell of a new baby chicken. The zygote
divides innumerable times to form all of the cells
of the complete animal. When small mutations
happen in the DNA that produces the zygote or even
by the mixing of male and female DNA, a new zygote
containing the mutations can produce a different
kind of chicken. So the first official
"domestic chicken" as we know it came out of an
egg, laid by a different ancestral chicken.
The zygote cell is the only cell where DNA
mutations could produce a new animal, and the
zygote is housed in the chicken's egg. This means
that the egg of the first domestic chicken came
first.
Here is another way to look at your question:
Scientists think that a group of egg-laying
feathered dinosaurs were probably the ancestors of
today's birds. It is thought that eggs evolved
more than 1 billion years ago, in oceanic species.
When land animals evolved, coming onto land, their
eggs had a tough covering to retain moisture on
dry land. Egg-laying animals like amphibians,
reptiles, and insects prospered. The first "land eggs" pre-dated chickens by about 250 million years. Click Here to return to the search form.
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